q139/random_k2/random_2.md

Alibaba Cloud
Alibaba Cloud

Object Storage Service

Product Introduction

Document Version: 20220707

Alibaba CloudAlibaba CloudObject Storage ServiceProduct IntroductionDocument Version: 20220707Object  St orage Service

Legal disclaimer

Product  Int roduct ion··Legal disclaim
er

Alibaba Cloud reminds you t o carefully read and fully underst and t he t erms and condit ions of t his legal
disclaimer before you read or use t his document . If you have read or used t his document , it  shall be deemed
as your t ot al accept ance of t his legal disclaimer.

1.  You shall download and obt ain t his document  from t he Alibaba Cloud websit e or ot her Alibaba Cloud-
aut horized channels, and use t his document  for your own legal business act ivit ies only. The cont ent  of
t his document  is considered confident ial informat ion of Alibaba Cloud. You shall st rict ly abide by t he
confident ialit y obligat ions. No part  of t his document  shall be disclosed or provided t o any t hird part y for
use wit hout  t he prior writ t en consent  of Alibaba Cloud.

2.  No part  of t his document  shall be excerpt ed, t ranslat ed, reproduced, t ransmit t ed, or disseminat ed by

any organizat ion, company or individual in any form or by any means wit hout  t he prior writ t en consent  of
Alibaba Cloud.

3.  The cont ent  of t his document  may be changed because of product  version upgrade, adjust ment , or

ot her reasons. Alibaba Cloud reserves t he right  t o modify t he cont ent  of t his document  wit hout  not ice
and an updat ed version of t his document  will be released t hrough Alibaba Cloud-aut horized channels
from t ime t o t ime. You should pay at t ent ion t o t he version changes of t his document  as t hey occur and
download and obt ain t he most  up-t o-dat e version of t his document  from Alibaba Cloud-aut horized
channels.

4.  This document  serves only as a reference guide for your use of Alibaba Cloud product s and services.
Alibaba Cloud provides t his document  based on t he "st at us quo", "being defect ive", and "exist ing
funct ions" of it s product s and services. Alibaba Cloud makes every effort  t o provide relevant  operat ional
guidance based on exist ing t echnologies. However, Alibaba Cloud hereby makes a clear st at ement  t hat
it  in no way guarant ees t he accuracy, int egrit y, applicabilit y, and reliabilit y of t he cont ent  of t his
document , eit her explicit ly or implicit ly. Alibaba Cloud shall not  t ake legal responsibilit y for any errors or
lost  profit s incurred by any organizat ion, company, or individual arising from download, use, or t rust  in
t his document . Alibaba Cloud shall not , under any circumst ances, t ake responsibilit y for any indirect ,
consequent ial, punit ive, cont ingent , special, or punit ive damages, including lost  profit s arising from t he
use or t rust  in t his document  (even if Alibaba Cloud has been not ified of t he possibilit y of such a loss).

5.  By law, all t he cont ent s in Alibaba Cloud document s, including but  not  limit ed t o pict ures, archit ect ure

design, page layout , and t ext  descript ion, are int ellect ual propert y of Alibaba Cloud and/or it s
affiliat es. This int ellect ual propert y includes, but  is not  limit ed t o, t rademark right s, pat ent  right s,
copyright s, and t rade secret s. No part  of t his document  shall be used, modified, reproduced, publicly
t ransmit t ed, changed, disseminat ed, dist ribut ed, or published wit hout  t he prior writ t en consent  of
Alibaba Cloud and/or it s affiliat es. The names owned by Alibaba Cloud shall not  be used, published, or
reproduced for market ing, advert ising, promot ion, or ot her purposes wit hout  t he prior writ t en consent  of
Alibaba Cloud. The names owned by Alibaba Cloud include, but  are not  limit ed t o, "Alibaba Cloud",
"Aliyun", "HiChina", and ot her brands of Alibaba Cloud and/or it s affiliat es, which appear separat ely or in
combinat ion, as well as t he auxiliary signs and pat t erns of t he preceding brands, or anyt hing similar t o
t he company names, t rade names, t rademarks, product  or service names, domain names, pat t erns,
logos, marks, signs, or special descript ions t hat  t hird part ies ident ify as Alibaba Cloud and/or it s
affiliat es.

6.  Please direct ly cont act  Alibaba Cloud for any errors of t his document .

> Document  Version: 20220707

I

Object  St orage Service

Product  Int roduct ion··Document  con
vent ions

Document conventions

St yle
St yle

Descript io n
Descript io n

Example
Example

Danger
 Danger

W arning
 W arning

No t ice
 No t ice

 No t eNo t e

>

Bo ldBo ld

A danger notice indicates a situation that
will cause major system changes, faults,
physical injuries, and other adverse
results.

Danger:
 Danger:

Resetting will result in the loss of user
configuration data.

A warning notice indicates a situation
that may cause major system changes,
faults, physical injuries, and other adverse
results.

W arning:
 W arning:

Restarting will cause business
interruption. About 10 minutes are
required to restart an instance.

A caution notice indicates warning
information, supplementary instructions,
and other content that the user must
understand.

No t ice:
 No t ice:

If the weight is set to 0, the server no
longer receives new requests.

A note indicates supplemental
instructions, best practices, tips, and
other content.

No t e:
 No t e:

You can use Ctrl + A to select all files.

Closing angle brackets are used to
indicate a multi-level menu cascade.

Set t ings > Net w o rk

Set   net w o rk
Net w o rk> Set   net w o rk

Click Set t ings
t ype .
t ype

Bold formatting is used for buttons ,
menus, page names, and other UI
elements.

Click OKOK.

Courier font

Courier font is used for commands

Run the  cd /d C:/window  command to
enter the Windows system folder.

Italic

[] or [a|b]

{} or {a|b}

Italic formatting is used for parameters
and variables.

bae log list --instanceid

Instance_ID

T his format is used for an optional value,
where only one item can be selected.

ipconfig [-all|-t]

T his format is used for a required value,
where only one item can be selected.

switch {active|stand}

> Document  Version: 20220707

I

Object  St orage Service

Product  Int roduct ion··Table of Cont
ent s

Table of Contents

1.What  is  OSS?

2.Features

3.Benefits

4.Scenarios

5.FAQ

6.Terms

7.Limits

05

09

15

18

20

25

30

> Document  Version: 20220707

I

Object  St orage Service

Product  Int roduct ion··What  is OSS?

1.What is OSS?
1.What is OSS?

Alibaba Cloud Object  St orage Service (OSS) is a secure, cost -effect ive, and highly reliable cloud st orage
service t hat  allows you t o st ore a large amount  of dat a. OSS is designed t o provide 99.9999999999%
(t welve 9's) dat a durabilit y and 99.995% dat a availabilit y. OSS provides mult iple st orage classes t o help
you manage and reduce st orage cost s.

OSS support s REST ful API operat ions t hat  are independent  of t he OSS console. You can st ore and
access dat a from all applicat ions anyt ime and anywhere.

You can call API operat ions and use SDKs or OSS migrat ion t ools provided by Alibaba Cloud t o t ransfer
large amount s of dat a t o and from Alibaba Cloud OSS. You can use OSS bucket s of t he St andard
st orage class t o st ore image, audio, and video object s for apps and websit es. You can use OSS bucket s
of t he Infrequent  Access (IA), Archive, or Cold Archive st orage class t o st ore infrequent ly accessed
object s at  a low cost  and wit h longer st orage period.

Get started with O SS
Get started with O SS

Video t ut orial

T he following video quickly guides you t hrough OSS.

FAQ

For frequent ly asked quest ions about  OSS, see FAQ.

Learning pat h

OSS Learning Pat h helps you get  st art ed wit h OSS. You can learn basic OSS operat ions, and t hen
perform secondary development  by using a variet y of API operat ions, SDKs, and convenient  t ools.

Terms
Terms

st orage class

T he st orage class of a bucket  or an object . OSS provides t he following st orage classes t o cover a
variet y of dat a st orage scenarios from hot  dat a t o cold dat a: St andard, IA, Archive, and Cold Archive.
T he St andard st orage class provides high-durabilit y, high-availabilit y, and high-performance object
st orage services t hat  can support  frequent  dat a access. T he IA st orage class is suit able for st oring
dat a t hat  is accessed once or t wice a mont h. In addit ion, t he unit  price of IA st orage is lower t han
t hat  of St andard st orage. T he Archive st orage class is suit able for st oring archive dat a for at  least  six
mont hs. T he Cold Archive st orage class is suit able for st oring cold dat a over a long period of t ime.
For more informat ion about  st orage classes, see Overview.

bucket

A cont ainer used t o st ore object s in OSS. All object s are cont ained in bucket s. You can configure a
variet y of bucket  at t ribut es such as t he region, access cont rol list  (ACL), and st orage class. You can
creat e bucket s of different  st orage classes t o st ore your dat a.

object

T he basic unit  used t o st ore dat a in OSS. Object s are also known as files. An object  consist s of object
met adat a, object  dat a, and an object  key. T he key of an object  uniquely ident ifies t he object  in a
bucket . Object  met adat a consist s of key-value pairs t hat  describe object  at t ribut es, such as t he last
modified t ime and t he size of t he object . You can also specify t he user met adat a of an object .

region

> Document  Version: 20220707

5

Product  Int roduct ion··What  is OSS?

Object  St orage Service

T he physical locat ion of an OSS dat a cent er. You can select  a region t o creat e a bucket  based on t he
cost  and locat ion of t he request s t o t he bucket . For more informat ion, see Regions and endpoints.

endpoint

T he domain name t hat  is used t o access OSS. OSS uses REST ful API operat ions t o provide services.
Different  regions are accessed by using different  endpoint s. Access over t he int ernal net work or over
t he Int ernet  wit hin t he same region also uses different  endpoint s. For more informat ion, see Regions
and endpoints.

AccessKey pair

T he access credent ial t hat  is used t o aut hent icat e a request er. An AccessKey pair consist s of an
AccessKey ID and an AccessKey secret . OSS uses symmet ric encrypt ion based on AccessKey pairs t o
verify t he ident it y of a request er. T he AccessKey ID is used t o ident ify a user. T he AccessKey secret  is
used t o encrypt  and verify signat ure st rings. T he AccessKey secret  must  be kept  confident ial. For
more informat ion about  how t o obt ain an AccessKey pair, see Obtain an AccessKey pair.

Common operations
Common operations

Creat e bucket s

Before you can upload object s t o OSS, you must  creat e a bucket . You can configure various
at t ribut es such as t he region, ACL, and ot her met adat a for a bucket . For more informat ion about  how
t o creat e a bucket , see Create buckets.

Upload object s

Aft er you creat e a bucket , you can upload object s of different  sizes t o t he bucket . For more
informat ion about  how t o upload object s, see Upload objects.

Download object s

Aft er you upload object s t o a bucket , you can download t he object s t o t he default  download pat h
of your browser or t he specified local pat h. For more informat ion about  how t o download object s,
see Download objects.

List  object s

You can list  all object s in a bucket . If a large number of object s are st ored in a bucket , you can also
list  some of t he object s in t he bucket . For more informat ion about  how t o list  object s, see List objects.

Delet e object s

You can manually delet e one or more object s t hat  you no longer need. You can also configure
lifecycle rules t o allow OSS t o aut omat ically delet e a single object  or mult iple object s. For more
informat ion about  how t o delet e object s, see Delete objects.

Features
Features

Versioning

OSS allows you t o configure versioning for a bucket  t o prot ect  object s t hat  are st ored in t he bucket .
Aft er you enable versioning for a bucket , dat a t hat  is overwrit t en or delet ed in t he bucket  is saved as
a previous version. You can use versioning t o recover a previous version of an object  t hat  is
accident ally overwrit t en or delet ed. For more informat ion about  versioning, see Overview.

Bucket  Policy

6

> Document  Version: 20220707

Object  St orage Service

Product  Int roduct ion··What  is OSS?

T he owner of a bucket  can configure bucket  policies t o grant  users different  permissions t o access
t he specified OSS resources in t he bucket . For example, you can configure bucket  policies t o
aut horize ot her Alibaba Cloud account s or anonymous users t o access or manage all or some
resources in your bucket . You can also configure bucket  policies t o grant  full permissions such as
read-only, read/writ e, or full permissions t o different  RAM users of t he same Alibaba Cloud account .
T his way, different  RAM users have different  permissions t o access or manage resources in your
bucket . For more informat ion about  how t o configure bucket  policies, see Configure bucket policies to
authorize other users to access OSS resources.

CRR

Cross-region replicat ion (CRR) provides aut omat ic and asynchronous (near real-t ime) replicat ion of
object s across bucket s in different  OSS regions. Operat ions such as creat ing, overwrit ing, and
delet ing object s can be synchronized from a source bucket  t o a dest inat ion bucket . CRR can meet
your requirement s for cross-region disast er recovery and dat a replicat ion. For more informat ion about
CRR, see CRR.

Dat a encrypt ion

Server-side encrypt ion: When you upload an object  t o a bucket  for which server-side encrypt ion is
enabled, OSS encrypt s t he object  and st ores t he encrypt ed object . When you download t he
encrypt ed object  from OSS, OSS aut omat ically decrypt s t he object  and ret urns t he decrypt ed object .
A header is added in t he response t o indicat e t hat  t he object  is encrypt ed on t he OSS server. For
more informat ion about  server-side encrypt ion, see Server-side encryption.

Client -side encrypt ion: Before you upload an object  t o a bucket , t he object  is encrypt ed on t he local
client . For more informat ion about  client -side encrypt ion, see Client-side encryption.

Manage O SS
Manage O SS

You can use a variet y of met hods t o upload object s, download object s, and manage OSS.

Manage OSS by using t he OSS console

OSS provides a web-based console. You can log on t o t he OSS console t o manage your OSS
resources. For more informat ion, see Use Alibaba Cloud accounts to log on to the OSS console.

Manage OSS by using API operat ions or SDKs

OSS provides REST ful API operat ions and SDKs for mult iple programming languages t o facilit at e
secondary development . For more informat ion, see List of operations by function and Overview.

Manage OSS by using t ools

OSS provides mult iple management  t ools, such as ossbrowser, ossut il, and ossft p. For more
informat ion, see OSS tools.

Manage OSS by using CSG

OSS uses a flat  st ruct ure inst ead of a hierarchical st ruct ure t o st ore object s. All element s are st ored
as object s in bucket s. T o use OSS in t he same manner in which local file syst ems are used, you can
configure Cloud St orage Gat eway (CSG). For more informat ion, visit  t he CSG product  page.

Pricing
Pricing

> Document  Version: 20220707

7

Product  Int roduct ion··What  is OSS?

Object  St orage Service

T radit ional st orage service providers require you t o purchase a reserved amount  of st orage capacit y
and net work t raffic before you use resources. If your st orage capacit y or t raffic usage exceeds t he
reserved amount , your service is deact ivat ed or you are charged excess fees. At  t he same t ime, if your
st orage capacit y or t raffic usage does not  exceed t he reserved amount , you are charged for t he full
amount  of t he st orage and t raffic.

OSS charges you only for t he st orage capacit y and t raffic t hat  you consume. T herefore, you do not
need t o purchase st orage capacit y and t raffic before you use resources. You can t ake t he cost
advant ages of t he flexible infrast ruct ure provided by Alibaba Cloud t o grow your business.

For more informat ion about  OSS pricing, go t o t he Pricing t ab of t he OSS product  page. For more
informat ion about  OSS billing met hods, see Overview.

Related services
Related services

Aft er you upload your dat a t o OSS, you can use ot her Alibaba Cloud feat ures and services t o manage
your dat a.

T he following feat ures and services are frequent ly used wit h OSS:

Image Processing (IMG): a service t hat  allows you t o perform a variet y of operat ions such as format
convert ing, resizing, cropping, rot at ing, and adding wat ermarks t o images st ored in OSS. For more
informat ion, see IMG implement at ion modes.

Elast ic Comput e Service (ECS): a cloud comput ing service t hat  provides elast ic and efficient
comput ing capabilit y. For more informat ion, visit  t he ECS product  page.

Alibaba Cloud CDN: a dist ribut ed net work t hat  caches resources from an origin server t o edge nodes
in different  regions t o accelerat e cont ent  delivery. For more informat ion, visit  t he CDN product  page.

E-MapReduce (EMR): a big dat a processing solut ion built  on ECS. EMR is developed based on open
source Apache Hadoop and Apache Spark t o facilit at e dat a analysis and processing. For more
informat ion, visit  t he E-MapReduce product  page.

ApsaraVideo Media Processing: a service t hat  convert s audio or video object s st ored in OSS int o files
t hat  are suit able for playback on PCs, T Vs, and mobile devices. Deep learning result s from large
amount s of dat a help ApsaraVideo Media Processing perform mult imodal analysis on t he audio, t ext ,
and images in video files and t he cont ent  of audio files. ApsaraVideo for Media Processing uses t he
analysis result s t o int elligent ly audit , underst and, and edit  t he cont ent  of t he audio or video files. For
more informat ion, visit  t he ApsaraVideo Media Processing product  page.

Dat a Online Migrat ion: a service t hat  allows you t o migrat e dat a from a t hird-part y st orage service
such as Amazon Web Services (AWS) and Google Cloud t o OSS wit h ease. For more informat ion, see
Dat a Online Migrat ion document at ion.

Dat a T ransport : a service t hat  helps you migrat e large amount s of dat a from local st orage t o OSS.
For example, you can use Dat a T ransport  t o migrat e t erabyt es or pet abyt es of local dat a t o OSS
when t he local net work bandwidt h is insufficient  and expansion cost s are high. For more informat ion,
see What  is Dat a T ransport ?

Alibaba Cloud storage services
Alibaba Cloud storage services

In addit ion t o OSS, Alibaba Cloud also provides a variet y of st orage services such as file st orage and
block st orage for different  scenarios. For more informat ion about  Alibaba Cloud st orage services, see
Overview.

For more informat ion about  use cases and solut ions of Alibaba Cloud st orage services, visit  t he Alibaba
Cloud St orage.

8

> Document  Version: 20220707

Object  St orage Service

Product  Int roduct ion··Feat ures

2.Features
2.Features

Object  St orage Service (OSS) provides secure, cost -effect ive, and high-durabilit y services for you t o
st ore large amount s of dat a in t he cloud. T his t opic describes t he common scenarios and corresponding
feat ures of OSS. You can select  t he best  solut ion based on your business requirement s.

Before you use OSS, we recommend t hat  you have a good underst anding of t he basic t erms used in
OSS, including bucket s, object s, regions, and endpoint s. For more informat ion, see T erms.

T he following t able describes t he feat ures provided by OSS.

Scenario

Feature

References

Upload objects

Search for objects

Download objects

Share objects

Query objects

Before you upload objects to OSS, you must
create a bucket in an Alibaba Cloud region to
store uploaded objects. After you create a
bucket, you can upload objects to the bucket.

Create buckets

Create directories

Simple upload

OSS allows you to search for objects and
directories to find the object that you want to
access in a bucket.

Search for objects

After you upload objects to a bucket, you can
download the objects to the default
download path of your browser or a specified
local path.

Download objects

After you upload an object to a bucket, you
can share the object URL with third parties for
downloads or previews.

Share objects

OSS provides the data indexing feature to
allow you to index the metadata of objects.
You can specify the metadata of objects as
index conditions to query objects. T his way,
you can efficiently manage and learn about
data structures, perform queries, collect
statistics, and manage objects.

Data indexing

Delete objects or
directories

OSS allows you to delete one or more objects,
directories, and parts at a time. You can delete
expired objects at regular intervals to save
storage space.

Delete objects

Delete directories

Manage parts

Automatically delete
multiple objects at a
specified period of time

OSS supports lifecycle rules. You can configure
lifecycle rules to periodically convert the
storage class of non-hot data to Infrequent
Access (IA), Archive, or Cold Archive. You can
also configure lifecycle rules to delete expired
data.

Overview

> Document  Version: 20220707

9

Product  Int roduct ion··Feat ures

Object  St orage Service

Scenario

Feature

References

Accelerate the upload and
download of data

Recover the data that is
accidentally deleted

Zone-disaster recovery

Geo-disaster recovery

OSS supports transfer acceleration. T ransfer
acceleration uses optimal route selection and
protocol stack tuning to reduce timeouts in
remote transmission and improve user
experience.

OSS supports versioning. After you enable
versioning for a bucket, OSS saves the
overwritten and deleted objects as previous
versions in the bucket. You can configure
versioning to recover an object to a previous
version when the object is accidentally
overwritten or deleted.

You can store data in and migrate the data
across three zones in the same region by using
zone-redundant storage (ZRS). If one zone
becomes unavailable, you can continue to
access the data that is stored in the other two
zones. T his feature is designed to provide
99.9999999999% (twelve 9's) data durability
and 99.995% service availability.

OSS supports cross-region replication (CRR).
You can use CRR to synchronize operations
such as creation, update, and deletion of data
from the source bucket to the destination
bucket in a different region. T his way, you can
implement geo-disaster recovery.

T ransfer acceleration

Overview

ZRS

CRR

Retention policy

OSS supports the Write Once Read Many
(WORM) feature. T he feature helps prevent
objects from being deleted or overwritten
within a specified period of time.

合规保留策略

10

> Document  Version: 20220707

Object  St orage Service

Product  Int roduct ion··Feat ures

Scenario

Feature

References

Control access to data

OSS supports flexible authorization and
authentication mechanisms. You can control
access to your OSS resources by using the
following methods:

ACL: You can set access control lists (ACLs)
for buckets and objects, including public
read/write, public read, and private.

Bucket policy: You can configure bucket
policies to authorize other users to access
your OSS resources in the OSS console. For
example, you can authorize RAM users of
other Alibaba Cloud accounts and
anonymous users from specific IP addresses
to access your OSS resources.

RAM policy: You can create RAM policies to
control access to buckets and directories.
OSS provides RAM Policy Editor to generate
required RAM policies. For more information,
see RAM Policy Editor.

ST S temporary authorization: You can use
Alibaba Cloud Security T oken Service (ST S)
to grant a third-party application or a RAM
user temporary access credentials with a
custom validity period.

Hotlink protection: You can configure a
Referer whitelist to prevent unauthorized
users from accessing your OSS resources.

Bucket ACL

Configure ACL for
objects

Bucket Policy

RAM Policy

Use a temporary
credential provided by
ST S to access OSS

Hotlink protection

Encrypt data

OSS supports client-side and server-side
encryption. You can select an encryption
method to encrypt and store your data in OSS.

Client-side encryption

Server-side encryption

OSS DDoS protection

OSS DDoS protection is a proxy-based attack
mitigation service that integrates OSS with
Anti-DDoS Pro and Anti-DDoS Premium. When a
bucket with OSS DDoS protection enabled
becomes a victim of DDoS attacks, OSS DDoS
protection diverts incoming traffic to an Anti-
DDoS Pro or Anti-DDoS Premium instance for
scrubbing and then redirects normal traffic to
the bucket. T his ensures the continuity of your
business in the event of DDoS attacks.

OSS DDoS protection

> Document  Version: 20220707

11

Product  Int roduct ion··Feat ures

Object  St orage Service

Scenario

Feature

References

Integrate with data lake

Manage data by category

OSS-HDFS (JindoFS service) is a cloud native
data lake storage service. OSS-HDFS is built on
unified metadata management capabilities and
is fully compatible with Hadoop Distributed File
System (HDFS) API operations. T he Portable
Operating System Interface (POSIX) is
supported in OSS-HDFS. T his helps OSS-HDFS
handle data lake computing scenarios in the
big data and AI fields.

OSS allows you to configure tagging to
manage data based on the data category:

Configure bucket tags: You can manage
data based on bucket tags. For example,
you can list buckets that have specified tags
and configure the ACLs of buckets that have
specified tags.

Configure object tags: You can manage
data based on object tags. For example, you
can configure lifecycle rules and ACLs for
objects that have specified tags.

Overview of the OSS-HDFS
service

Configure bucket
tagging

Object tagging

Record the access
information for OSS
resources

OSS supports logging. You can configure
logging to collect access statistics, audit
access to OSS, track exceptions, and
troubleshoot problems.

Use custom domain names
to access OSS resources

OSS allows you to map custom domain names
to OSS buckets and use the custom domain
names to access data in the buckets. If you
want to use your custom domain name to
access OSS over HT T PS, you can host your
Secure Sockets Layer (SSL) certificate in OSS.

Real-time log query

Logging

Map custom domain
names

Host SSL certificates

Static website hosting

OSS supports static website hosting. You can
configure static website hosting for your
bucket and access static websites by using the
bucket domain name.

Overview

CORS

OSS supports cross-origin resource sharing
(CORS) in HT ML5. CORS allows web application
clients that are loaded in one domain name to
interact with resources in another domain.

Configure CORS

12

> Document  Version: 20220707

Object  St orage Service

Product  Int roduct ion··Feat ures

Scenario

Feature

References

Obtain data from the
origin

Query object metadata

Modify HT T P headers

View the details of
resource usage

T raffic throttling

Analyze and process data

OSS supports back-to-origin configurations. If
your user accesses data in a bucket that has no
back-to-origin rules configured and the data
does not exist, 404 Not Found is returned.
However, if you configure back-to-origin rules
that contain the correct origin URLs, users can
obtain the data from the origin based on the
back-to-origin rules. You can configure back-
to-origin rules for hot data migration and
specific request redirection.

OSS supports the inventory feature. You can
configure inventories for buckets to export the
metadata of specified objects, including the
object sizes and encryption status.

OSS allows you to modify the HT T P headers of
objects. You can configure HT T P headers to
specify custom HT T P request policies, such as
the cache policy and forced object download
policy.

Overview

Bucket inventory

Configure object
metadata

OSS supports the monitoring feature. You can
use the monitoring feature to view real-time
information about OSS service usage, such as
the running status and performance of the
system.

Overview

OSS supports single-connection bandwidth
throttling. You can configure single-connection
bandwidth throttling for upload, download,
and copy operations on OSS objects to ensure
sufficient bandwidth for your other
applications.

OSS provides Image Processing (IMG) and video
snapshot capturing for you to analyze and
process data stored in OSS:

IMG: You can perform operations on images
stored in OSS, such as format conversion,
cropping, scaling, rotating, and
watermarking. You can also encapsulate
multiple operations into a style to process
images stored in OSS.

Video snapshot capturing: You can capture
images from video objects in the H.264
format.

Single-connection
bandwidth throttling

Overview

Video snapshots

Use tools to manage OSS
resources

OSS provides graphical, command-line, file
mounting, and FT P tools for you to manage
your OSS resources.

OSS tools

> Document  Version: 20220707

13

Product  Int roduct ion··Feat ures

Object  St orage Service

Scenario

Feature

Use OSS SDKs to manage
OSS resources

OSS provides SDKs for a variety of
programming languages to facilitate custom
development.

References

Overview

14

> Document  Version: 20220707

Object  St orage Service

Product  Int roduct ion··Benefit s

3.Benefits
3.Benefits

Object  St orage Service (OSS) is a secure, cost -effect ive, and high-durabilit y service t hat  enables you t o
st ore large amount s of dat a in Alibaba Cloud. T his t opic compares OSS wit h t he t radit ional self-
managed server st orage t o help you bet t er underst and t he benefit s of OSS.

Advantages of O SS over self-managed server storage
Advantages of O SS over self-managed server storage

Item

OSS

Self-managed server storage

Durability

Security

OSS is the core infrastructure of data
storage for Alibaba Group. T his reliable
and highly available service is one of the
backbone services that ensure stability
during the peak hours of Double 11. OSS
comes with a multi-redundant
architecture to provide reliable data
storage. In addition, OSS is built on a
high-availability architecture to eliminate
single points of failure (SPOFs) and
ensure the continuity of your services.

Provides service availability of at least
99.995%.

Provides data durability of at least
99.9999999999% (twelve 9's).

Automatically expands capacities
without affecting your services.

Offers automatic data redundancy.

Provides multi-level security
protection for enterprises, including
features such as server-side
encryption, client-side encryption,
hotlink protection, bucket policies that
specify IP address blacklists or
whitelists, fine-grained access control,
log audit, and the Write Once Read
Many (WORM) strategy.

Provides resource isolation
mechanisms for multiple tenants and
supports geo-disaster recovery.

Complies with the regulations of
multiple organizations including the
U.S. Securities and Exchange
Commission (SEC) and Financial
Industry Regulatory Authority, Inc.
(FINRA), which delivers services that
can meet the requirements of your
enterprise for data security and
compliance.

Prone to errors due to hardware
failures. If a disk has a bad sector,
data may be lost.

Requires manual restoration of data,
which can be a complex, time-
consuming, and labor-intensive
process.

Requires additional scrubbing devices
and blackhole policy-related services.

Requires a separate security
mechanism.

> Document  Version: 20220707

15

Product  Int roduct ion··Benefit s

Object  St orage Service

Item

OSS

Self-managed server storage

Requires manual expansion of storage
space due to limited capacity of hard
disks.

Offers limited bandwidth due to slow
single-line or double-line access.
Requires the manual expansion during
peak hours.

Requires dedicated O&M personnel,
which results in high costs.

Requires separate purchase and
deployment of data processing
capabilities.

Cost

Intelligent storage

Allows you to use multi-line Border
Gateway Protocol (BGP) to connect to
operator backbone network lines with
sufficient bandwidth resources.
Upstream traffic is free of charge.

Requires no hosting fees or the need
to hire O&M personnel.

Provides multiple data processing
capabilities, such as Image Processing
(IMG), video snapshot, document
preview, image scenario recognition,
facial recognition, and SQL in-place
query. OSS can be seamlessly integrated
with the Hadoop ecosystem and Alibaba
Cloud services such as Function
Compute, E-MapReduce (EMR), Data Lake
Analytics (DLA), BatchCompute,
MaxCompute, and Database Backup
(DBS) to manage and analyze data of
enterprises.

Additional benefits of O SS
Additional benefits of O SS

Ease of use

OSS provides st andard REST ful API operat ions, a wide range of SDKs, client  t ools, and t he OSS
console. You can upload, download, ret rieve, and manage large amount s of dat a used for
websit es and mobile apps in t he same way you use regular file syst ems.

T he capacit y of each bucket  is unlimit ed. T herefore, you can expand your bucket s in OSS based on
your requirement s.

OSS support s st reaming writ es and reads. It  is suit able for business scenarios t hat  require
simult aneous writ e and read of large files such as videos.

OSS support s lifecycle management . You can configure lifecycle rules t o bat ch delet e expired
object s or convert  t he st orage classes of expired object s t o cost -effect ive Infrequent  Access (IA),
Archive, or Cold Archive.

Powerful and flexible securit y mechanisms

OSS provides Securit y T oken Service (ST S) and URL aut hent icat ion and aut horizat ion. OSS also
support s IP address blacklist s or whit elist s, hot link prot ect ion, and Resource Access Management
(RAM).

OSS provides resource isolat ion mechanisms for users. You can also use t he mult i-clust er
synchronizat ion service.

OSS provides server-side encrypt ion, client -side encrypt ion, and encrypt ed t ransmission based on
Secure Socket s Layer (SSL) or T ransport  Layer Securit y (T LS) t o prot ect  dat a from pot ent ial securit y
risks on t he cloud.

16

> Document  Version: 20220707

Object  St orage Service

Product  Int roduct ion··Benefit s

OSS provides t he versioning feat ure t o prevent  object s from being accident ally delet ed or
overwrit t en.

Dat a redundancy mechanism

OSS uses a dat a redundant  st orage mechanism t o st ore copies of each object  in mult iple devices of
different  facilit ies in t he same region. T his way, OSS ensures dat a durabilit y and availabilit y even if
hardware failures occur.

Operat ions performed on object s in OSS are st rongly consist ent . For example, aft er you upload or
copy an object , t he uploaded or copied object  can be immediat ely read and copies of t he object
are writ t en t o mult iple devices for redundancy.

T o ensure t hat  dat a is complet ely t ransmit t ed, OSS calculat es t he checksum of t he net work t raffic
packet s t o check for errors when packet s are t ransmit t ed bet ween t he client  and t he server.

T he dat a redundancy mechanism of OSS can prevent  dat a loss even when t wo st orage facilit ies
are damaged at  t he same t ime.

Aft er dat a is st ored in OSS, OSS regularly checks whet her copies of t he dat a are lost . T hen, OSS
recovers lost  copies t o ensure dat a durabilit y and dat a availabilit y.

OSS periodically verifies t he int egrit y of dat a t o det ect  dat a corrupt ion caused by errors such as
hardware failures. If dat a is part ially corrupt ed or lost , OSS uses t he ot her copies t o reconst ruct
and repair t he corrupt ed dat a.

Rich and powerful value-added services

IMG: support s format  conversion, t humbnails, cropping, wat ermarking, and resizing for object s in
format s such as JPG, PNG, BMP, GIF, WebP, and T IFF.

Audio or video t ranscoding: provides high-qualit y, high-speed, and parallel audio or video
t ranscoding capabilit ies. T his way, your audio or video files can be played on different  t erminal
devices.

T ransfer accelerat ion over t he Int ernet : provides t he t ransfer accelerat ion service, which uses
opt imal rout e select ion and prot ocol st ack t uning t o reduce t imeout s in remot e t ransmission and
improve user experience. For more informat ion, see T ransfer accelerat ion.

Accelerat ed cont ent  delivery: uses OSS as t he origin and works wit h Cont ent  Delivery Net work
(CDN) t o improve user experience when t he same object  is repeat edly downloaded.

> Document  Version: 20220707

17

Product  Int roduct ion··Scenarios

Object  St orage Service

4.Scenarios
4.Scenarios

T his t opic describes t he applicat ion scenarios of OSS.

Massive storage for image, audio, and video applications
Massive storage for image, audio, and video applications

OSS can be used t o st ore large amount s of dat a, such as images, audio and video, and logs. You can
use a variet y of devices, websit es, and mobile applicat ions t o read dat a from or writ e dat a t o OSS. You
can writ e dat a t o OSS by uploading files or using st reams.

Dynamic and static content separation for websites and mobile
Dynamic and static content separation for websites and mobile
applications
applications

By using t he high bandwidt h provided by OSS, you can concurrent ly download a large amount  of dat a
from OSS over t he Int ernet . OSS provides T ransfer acceleration t hat  accelerat es uploads and downloads
across count ries and cont inent s and improves user experience. You can also use OSS wit h Cont ent
Delivery Net work (CDN) t o deliver st at ic dat a st ored in OSS t o CDN edge nodes. Users can access t he
dat a cached on CDN edge nodes inst ead of t he same dat a st ored in OSS. T his way, t he concurrent  and
repeat ed download of an object  wit hin t he same region can be accelerat ed.

Cloud data processing
Cloud data processing

18

> Document  Version: 20220707

Object  St orage Service

Product  Int roduct ion··Scenarios

Aft er you upload object s t o OSS, you can use ApsaraVideo for Media Processing and Image Processing
(IMG) t o process t he uploaded dat a.

> Document  Version: 20220707

19

Product  Int roduct ion··FAQ

Object  St orage Service

5.FAQ
5.FAQ

T his t opic provides answers t o frequent ly asked quest ions about  Object  St orage Service (OSS).

General FAQ
General FAQ

What  is Alibaba Cloud OSS?

Alibaba Cloud OSS is a secure, cost -effect ive, and scalable st orage service t hat  has high durabilit y
and is capable of processing large amount s of dat a. OSS is designed for dat a durabilit y of at  least
99.9999999999% (t welve 9's) and provides service availabilit y of at  least  99.995%.

What  are t he feat ures of OSS?

OSS support s REST ful API operat ions t hat  are independent  of t he OSS console. You can st ore and
access dat a from all applicat ions anyt ime and anywhere. OSS is highly scalable. You are charged only
for t he resources t hat  you use. You can scale OSS resources based on your requirement s wit hout
compromising performance or durabilit y.

You can call API operat ions and use SDKs or OSS migrat ion t ools provided by Alibaba Cloud t o
t ransfer large amount s of dat a t o and from Alibaba Cloud OSS. You can use OSS bucket s of t he
St andard st orage class t o st ore image, audio, and video object s for apps and websit es. You can use
OSS bucket s of t he Infrequent  Access (IA), Archive, or Cold Archive st orage class t o st ore infrequent ly
accessed object s at  a low cost  and wit h longer st orage period.

For more informat ion about  t he feat ures of OSS, see Features.

Who are t he int ended users of OSS?

OSS is an ideal solut ion for users who need t o st ore large amount s of dat a. T hese users include app
and soft ware developers, game development  ent erprises, and webmast ers of online communit ies,
media-sharing sit es, and e-commerce websit es.

What  dat a does OSS st ore?

OSS is suit able for st oring at t achment s, high-definit ion images, audio and video object s, and backup
object s for forums, websit es, and soft ware applicat ions, as well as object s for a variet y of
applicat ions, file synchronizat ion soft ware, and online st orage syst ems.

What  are t he advant ages of OSS over local st orage solut ions?

OSS allows developers t o make full use of t he economy of scale of Alibaba Cloud at  minimal cost
wit hout  addit ional invest ment s or affect ing performance. Developers can focus on t heir own
innovat ions wit hout  performance bot t lenecks and securit y risks t hat  come wit h increasing business
scales. OSS is cost -effect ive and easy t o use.

What  is t he upper limit  of t he dat a volume t hat  OSS can support ?

OSS does not  impose limit s on t he t ot al st orage capacit y and t he capacit y of a bucket . You can use
t he OSS console t o upload an object  up t o 5 GB in size. T o upload an object  larger t han 5 GB in size,
use mult ipart  upload, resumable upload, ossbrowser, or ossut il. For more informat ion, see Multipart
upload, Quick start, and Overview.

What  st orage classes does OSS provide?

20

> Document  Version: 20220707

Object  St orage Service

Product  Int roduct ion··FAQ

T he st orage class of a bucket  or an object . OSS provides t he following st orage classes t o cover a
variet y of dat a st orage scenarios from hot  dat a t o cold dat a: St andard, IA, Archive, and Cold Archive.
T he St andard st orage class provides high-durabilit y, high-availabilit y, and high-performance object
st orage services t hat  can support  frequent  dat a access. T he IA st orage class is suit able for st oring
dat a t hat  is accessed once or t wice a mont h. In addit ion, t he unit  price of IA st orage is lower t han
t hat  of St andard st orage. T he Archive st orage class is suit able for st oring archive dat a for at  least  six
mont hs. T he Cold Archive st orage class is suit able for st oring cold dat a over a long period of t ime.
For more informat ion about  st orage classes, see Overview.

Will Alibaba Cloud use t he dat a t hat  I st ore in OSS?

Alibaba Cloud does not  use or release your dat a wit hout  aut horizat ion. Alibaba Cloud processes user
dat a only based on your service requirement s or requirement s of laws and regulat ions. For more
informat ion, see Service t erms.

Does Alibaba Cloud use OSS t o st ore t heir own dat a?

Yes, Alibaba Cloud developers also use OSS t o st ore aut horized dat a for many project s. T hese
project s rely on OSS t o perform key business operat ions.

How does OSS ensure availabilit y when my OSS service experiences burst s of t raffic from
applicat ions?

OSS is designed t o address burst s of t raffic from Int ernet  applicat ions. Pay-as-you-go is used as a
billing met hod. T o ensure service cont inuit y during burst s of t raffic, OSS does not  impose capacit y
limit s. OSS ensures load balancing so t hat  applicat ions are not  affect ed by burst s of t raffic.

How is OSS dat a organized?

OSS is a dist ribut ed object  st orage service t hat  st ores dat a as key-value pairs. When you st ore an
object , you must  specify an object  name (key). T he key can t hen be used t o obt ain t he cont ent  of
t he object .

Keys can also be used t o simulat e cert ain feat ures of direct ories. OSS uses a flat  st ruct ure for object s
inst ead of a hierarchical st ruct ure. All element s are st ored as object s in bucket s. However, OSS
support s direct ories as a concept  t o group object s and simplify management . When you use APIs or
SDKs t o configure an object , you can specify t he key value, a full name t hat  includes a prefix for t he
object  t o manage ot her object s. For example, if you set  t he key of an object  t o   dir/example.jpg  ,
a direct ory named   dir   is creat ed in t he current  bucket  and an object  named   example.jpg   is
creat ed in t he direct ory. If you delet e t he   dir/example.jpg   object , t he   dir   direct ory is also
delet ed.

How do I get  st art ed wit h OSS?

Before you use OSS, ensure t hat  you have creat ed an Alibaba Cloud account  and complet ed real-
name verificat ion. If you do not  have an Alibaba Cloud account , t he syst em prompt s you t o creat e an
Alibaba Cloud account  when you act ivat e OSS. For more informat ion, see Creat e Your Alibaba Cloud
Account . Aft er you creat e t he Alibaba Cloud account , visit  t he Object  St orage Service product
homepage. Click Act ivat e Now
go. T o furt her minimize OSS cost s, we recommend t hat  you purchase resource plans. For more
informat ion, see Buy OSS resource plans (subscript ion).

Act ivat e Now. By default , t he billing met hod aft er you act ivat e OSS is Pay-as-you-

You can get  st art ed wit h OSS by using t he OSS console, graphical management  t ool, command-line
management  t ool, and SDKs for various programming languages. For more informat ion, see Get
started with OSS.

FAQ  about Alibaba Cloud regions
FAQ  about Alibaba Cloud regions

> Document  Version: 20220707

21

Product  Int roduct ion··FAQ

Object  St orage Service

What  is an Alibaba Cloud region?

An Alibaba Cloud region is a geographical region t hat  cont ains mult iple geographically isolat ed
zones. T hese zones are connect ed t o each ot her by using net works t hat  feat ure short  lat ency, high
t hroughput , and high redundancy.

What  is a zone?

Each region cont ains several isolat ed locat ions known as zones. T he power supply and net work of
each zone are independent . T he net work lat ency bet ween inst ances wit hin t he same zone is short er.
Zones wit hin t he same region can access each ot her. However, fault s t hat  occur in one zone do not
affect  ot her zones.

How do I det ermine which region t o st ore my dat a?

When you select  a region, we recommend t hat  you consider fact ors such as physical locat ions,
relat ionships bet ween cloud services, and resource prices For more informat ion, see Choose an OSS
region.

FAQ  about billing
FAQ  about billing

How does OSS charge fees?

OSS provides t he pay-as-you-go billing met hod t hat  allows you t o pay for resources you use. No
minimum usage fees are imposed. You can also purchase resource plans. Resource plans are used t o
deduct  fees incurred by resource usage. In most  cases, resource plans are more cost -effect ive. For
more informat ion about  prices, visit  t he OSS pricing page.

How does OSS charge fees when ot her account s are used t o access my OSS resource?

When ot her account s access your OSS resources, OSS charges you based on st andard pricing. You can
enable t he pay-by-request er mode for your bucket  so t hat  request ers pay t he fees generat ed by
sending request s and downloading OSS dat a. For more informat ion, see Enable pay-by-requester.

FAQ  about data security and protection
FAQ  about data security and protection

Is dat a st ored in OSS secure?

OSS is secure. By default , only t he resource owner can access resources wit hin a bucket . OSS provides
user ident it y verificat ion t o cont rol access t o dat a. You can use various access cont rol policies on t he
bucket  or object  level, such as access cont rol list s (ACLs), t o grant  specific permissions t o specific
users and user groups. T he OSS console displays bucket s t hat  are available t o public access. You can
set  t he bucket  ACL t o privat e if you do not  want  ot her users t o access your bucket  or object . If you
set  t he bucket  ACL t o public read or public read/writ e, a message t hat  indicat es securit y risks
appears. For more informat ion about  t he securit y of OSS, see Overview.

How do I cont rol access t o my OSS dat a?

OSS provides mult iple access cont rol met hods, including ACLs, RAM policies, and bucket  policies, for
access t o object s st ored in bucket s. For more informat ion, see Overview.

What  dat a encrypt ion met hods does OSS provide?

Server-side encrypt ion: When you upload an object  t o a bucket  for which server-side encrypt ion is
enabled, OSS encrypt s t he object  and st ores t he encrypt ed object . When you download t he
encrypt ed object  from OSS, OSS aut omat ically decrypt s t he object  and ret urns t he decrypt ed object .
A header is added in t he response t o indicat e t hat  t he object  is encrypt ed on t he OSS server. For
more informat ion about  server-side encrypt ion, see Server-side encryption.

22

> Document  Version: 20220707

Object  St orage Service

Product  Int roduct ion··FAQ

Client -side encrypt ion: Before you upload an object  t o a bucket , t he object  is encrypt ed on t he local
client . For more informat ion about  client -side encrypt ion, see Client-side encryption.

How do I prevent  dat a st ored in bucket s from being accident ally delet ed or overwrit t en?

OSS allows you t o configure versioning for a bucket  t o prot ect  object s t hat  are st ored in t he bucket .
Aft er you enable versioning for a bucket , dat a t hat  is overwrit t en or delet ed in t he bucket  is saved as
a previous version. You can use versioning t o recover a previous version of an object  t hat  is
accident ally overwrit t en or delet ed. For more informat ion about  versioning, see Overview.

What  is a ret ent ion policy?

OSS support s t he Writ e Once Read Many (WORM) st rat egy t hat  prevent s an object  from being
delet ed or overwrit t en for a specified period of t ime. You can configure t ime-based ret ent ion
policies for bucket s. Aft er a ret ent ion policy is configured and locked for a bucket , you can read
object s from or upload object s t o t he bucket . However, object s in t he bucket  or t he ret ent ion policy
cannot  be delet ed wit hin t he ret ent ion period of t he ret ent ion policy. You can delet e t he object s
only aft er t he ret ent ion period expires.

You can configure ret ent ion policies when you need t o st ore infrequent ly accessed import ant  dat a
t hat  is not  allowed t o be modified or delet ed. Such dat a includes medical records, t echnical
document s, and cont ract s. You can st ore t hese object s in a specified bucket  and configure a
ret ent ion policy for t he bucket .

FAQ  about data replication
FAQ  about data replication

How do I replicat e dat a from a bucket  t o anot her bucket  in a different  region?

You can configure mult iple cross-region replicat ion (CRR) rules for a bucket  t o st ore mult iple copies of
t he dat a in different  regions. CRR provides aut omat ic and asynchronous (near real-t ime) replicat ion
of object s across bucket s in different  OSS regions. Operat ions such as creat ing, overwrit ing, and
delet ing object s can be synchronized from a source bucket  t o a dest inat ion bucket .

What  are t he advant ages of CRR?

Compliance requirement s: Alt hough OSS st ores mult iple replicas of each object  in physical disks,
replicas must  be st ored at  a dist ance from each ot her t o comply wit h regulat ions. CRR allows you
t o replicat e dat a bet ween geographically dist ant  OSS dat a cent ers t o sat isfy t hese compliance
requirement s.

Minimum lat ency: You have users who are locat ed in t wo geographical locat ions. T o minimize t he
lat ency when t he users access object s, you can maint ain replicas of object s in OSS dat a cent ers
t hat  are geographically closer t o t hese users.

Dat a backup and disast er recovery: You have high requirement s for dat a securit y and availabilit y,
and want  t o explicit ly maint ain replicas of all writ t en dat a in a second dat a cent er. If one OSS dat a
cent er is damaged in a cat ast rophic event  such as an eart hquake or a t sunami, you can use backup
dat a from t he ot her dat a cent er.

Dat a replicat ion: For business reasons, you may need t o migrat e dat a from one OSS dat a cent er t o
anot her dat a cent er.

Operat ional reasons: You have comput e clust ers deployed in t wo different  dat a cent ers t hat  need
t o analyze t he same group of object s. You can choose t o maint ain object  replicas in t hese regions.

How does OSS charge fees when I use CRR?

> Document  Version: 20220707

23

Product  Int roduct ion··FAQ

Object  St orage Service

Aft er CRR is enabled, cross-region t raffic is generat ed when you replicat e object s across bucket s in
t he source and dest inat ion regions. You are charged for t he t raffic t hat  is generat ed when you use
CRR. Each t ime an object  is synchronized, OSS calculat es t he number of request s and charges t he
request s on a pay-as-you-go basis. T he t raffic t hat  is generat ed when you use CRR can be charged
only on a pay-as-you-go basis. Resource plans are unavailable for CRR.

FAQ  about data query
FAQ  about data query

How do I query dat a in OSS?

OSS support s t he Select Object  operat ion t hat  allows you t o use SQL st at ement s t o query specific dat a
in a CSV or JSON object  inst ead of querying t he ent ire object . T he Select Object  operat ion simplifies t he
process used t o query dat a and filt er t he dat a int o smaller and more specific dat a set s. T herefore, t his
operat ion is suit able for t he mult ipart  query of large object s, query of JSON object s, and analysis of log
object s. For more informat ion about  dat a query, see Call the SelectObject operation to query objects.

FAQ  about storage management
FAQ  about storage management

What  is OSS lifecycle management ? How do I use lifecycle management  t o minimize OSS st orage
cost s?

You can configure a lifecycle rule t o regularly delet e object s t hat  are no longer accessed or convert
t he st orage class of cold dat a t o IA, Archive, or Cold Archive. T his makes dat a management  easier
and saves st orage cost s. For example, you can configure lifecycle rules in t he following scenarios:

A medical inst it ut ion st ores it s medical records in OSS. T hese object s are occasionally accessed
wit hin six mont hs aft er t hey are uploaded, and almost  never aft er t hat . In t his case, you can
configure a lifecycle rule t o convert  t he st orage class of t hese object s t o Archive 180 days aft er
t hey are uploaded.

A company st ores t he call records of it s service hot line in OSS. T hese object s are frequent ly
accessed wit hin t he first  t wo mont hs, occasionally aft er t wo mont hs, and almost  never aft er six
mont hs. Aft er t wo years, t hese object s no longer need t o be st ored. In t his case, you can configure
a lifecycle rule t o convert  t he st orage class of t hese object s t o IA 60 days aft er t hey are uploaded
and t o Archive 180 days aft er t hey are uploaded, and delet e t hem 730 days aft er t hey are
uploaded.

You can manually delet e up t o 1,000 object s each t ime. If a bucket  cont ains more t han 1,000
object s, you must  delet e t he object s mult iple t imes. In t his case, you can configure a lifecycle rule
t hat  is used t o delet e all object s in t he bucket  t he next  day. T his way, all object s in t he bucket  can
be delet ed t he next  day.

For more informat ion about  lifecycle management , see Lifecycle rules based on the last modified time.

How do I regularly obt ain t he informat ion about  object s st ored in a bucket ?

You can use t he bucket  invent ory feat ure t o export  t he informat ion about  specific object s in a
bucket  on a daily or weekly basis. Export ed object  informat ion includes t he number, sizes, st orage
classes, and encrypt ion st at us of t he object s. For more informat ion about  t he bucket  invent ory
feat ure, see Bucket inventory.

24

> Document  Version: 20220707

Object  St orage Service

Product  Int roduct ion··Terms

6.Terms
6.Terms

T his t opic describes several basic t erms used in Object  St orage Service (OSS).

bucket
bucket

T he cont ainer for OSS object s. Each object  in OSS is cont ained in a bucket . You can configure various
at t ribut es of a bucket , including t he region, access cont rol list  (ACL), and st orage class. You can creat e
bucket s of different  st orage classes t o st ore dat a based on your requirement s.

OSS does not  use a hierarchical st ruct ure for object s, but  inst ead uses a flat  st ruct ure. Each object
belongs t o a bucket .

You can creat e mult iple bucket s.

A bucket  name must  be unique in OSS wit hin an Alibaba Cloud account . Bucket  names cannot  be
changed aft er t he bucket s are creat ed.

A bucket  can cont ain an infinit e number of object s.

OSS support s t he following bucket  naming convent ions:

T he name can cont ain only lowercase let t ers, digit s, and hyphens (-).

T he name must  st art  and end wit h a lowercase let t er or a digit .

T he name must  be 3 t o 63 charact ers in lengt h.

object
object

T he basic unit  for dat a operat ions in OSS. Object s are also known as files. OSS does not  use a
hierarchical st ruct ure for object s, but  inst ead uses a flat  st ruct ure. All element s are st ored as object s in
bucket s. However, OSS support s direct ories as a concept  t o group object s and simplify management .
An object  is composed of object  met adat a, user dat a, and a key. A key is used t o ident ify an object  in a
bucket . Object  met adat a is a group of key-value pairs t hat  define t he propert ies of an object , such as
t he last  modified t ime and t he object  size. You can also assign user met adat a t o t he object .

T he lifecycle of an object  st art s when t he object  is uploaded, and ends when t he object  is delet ed.
T hroughout  t he lifecycle, cont ent  can be appended only t o object s creat ed by using append upload. If
you want  t o modify t he cont ent  of an object , you must  upload a new object  t hat  has t he same name
as t he exist ing object  t o replace t he exist ing object .

T he name of an object  must  comply wit h t he following convent ions:

T he name must  be encoded in UT F-8.

T he name must  be 1 t o 1,023 charact ers in lengt h.

T he name cannot  st art  wit h a forward slash (/) or a backslash (\).

Not e  Object  names are case-sensit ive. Unless ot herwise st at ed, object s and files
Not e

ment ioned in OSS document s are called object s.

O bjectKey
O bjectKey

In SDKs for different  programming languages, Object Key, Key, and Object Name indicat e t he full pat h of
t he object . You must  specify t he full pat h of an object  when you perform operat ions on t he object . For
example, when you upload an object  t o a bucket , Object Key indicat es t he full pat h t hat  includes t he
ext ension of t he object . For example, you can set  Object Key t o abc/efg/123.jpg.

> Document  Version: 20220707

25

Product  Int roduct ion··Terms

Object  St orage Service

region
region

T he physical locat ion of OSS resources. When you creat e a bucket , you can select  a region based on t he
cost  and source of t he request s. In most  cases, t he closer a user is locat ed from an OSS region, t he
fast er t he access. For more informat ion, see Regions and endpoints.

A region is specified when a bucket  is creat ed. Aft er a bucket  is creat ed, it s region cannot  be changed.
All object s in t his bucket  are st ored in t he corresponding region. Regions are configured for bucket s
inst ead of object s.

endpoint
endpoint

T he domain name t hat  is used t o access OSS. OSS uses HT T P REST ful APIs t o provide services. Different
regions are accessed by using different  endpoint s. A region has different  endpoint s for access over t he
int ernal net work and for access over t he Int ernet . For example, t he public endpoint  used t o access OSS
dat a in t he China (Hangzhou) region is oss-cn-hangzhou.aliyuncs.com, and t he int ernal endpoint  is oss-
cn-hangzhou-int ernal.aliyuncs.com. For more informat ion, see Regions and endpoints.

AccessKey pair
AccessKey pair

T he access credent ial t hat  is used t o ident ify t he request er. An AccessKey pair consist s of an AccessKey
ID and an AccessKey secret . OSS uses an AccessKey pair t o implement  symmet ric encrypt ion and verify
t he ident it y of a request er. T he AccessKey ID is used t o ident ify a user. T he AccessKey secret  is used t o
encrypt  and verify t he signat ure st ring. T he AccessKey secret  must  be kept  confident ial. OSS support s
AccessKey pairs obt ained by using t he following met hods:

T he bucket  owner applies for an AccessKey pair.

T he bucket  owner uses Resource Access Management  (RAM) t o assign an AccessKey pair t o a t hird
part y.

T he bucket  owner uses Securit y T oken Service (ST S) t o assign an AccessKey pair t o a t hird part y.

For more informat ion about  AccessKey pairs, see Obtain an AccessKey pair.

strong consistency
strong consistency

T he feat ure t hat  requires object  operat ions in OSS be at omic, which indicat es t hat  operat ions can
eit her succeed or fail wit hout  int ermediat e st at es. T o ensure t hat  users can access only complet e
object s, OSS does not  ret urn part ially uploaded object s.

Object  operat ions in OSS are highly consist ent . For example, when a user receives an upload (PUT )
success response, t he uploaded object  can be immediat ely read, and copies of t he object  are creat ed
for redundancy. T herefore, t he sit uat ions where dat a is not  obt ained when a user performs a read-
aft er-writ e operat ion do not  exist . T he same is t rue for delet e operat ions. Aft er a user delet es an
object , t he object  and it s copies no longer exist .

data redundancy mechanism
data redundancy mechanism

T he dat a redundancy mechanism t hat  is implement ed based on erasure coding and mult iple replicas.
Copies of each object  are st ored in different  servers wit hin t he same region. T his way, dat a durabilit y
and availabilit y are ensured when hardware failures occur.

Operat ions on object s in OSS are highly consist ent . For example, when a user receives an upload or
copy success response, t he uploaded object  can be immediat ely read, and copies of t he object  are
creat ed for redundancy.

T o ensure complet e dat a t ransmission, OSS calculat es t he checksum of t he net work t raffic packet s
and checks for errors when packet s are t ransmit t ed bet ween t he client  and t he server.

26

> Document  Version: 20220707

Object  St orage Service

Product  Int roduct ion··Terms

T he dat a redundancy mechanism of OSS can prevent  dat a loss even when t wo st orage facilit ies are
damaged at  t he same t ime.

Aft er dat a is st ored in OSS, OSS regularly checks whet her copies of t he dat a are lost . T hen, OSS
recovers lost  copies t o ensure dat a durabilit y and dat a availabilit y.

OSS periodically verifies t he int egrit y of dat a t o det ect  dat a corrupt ion caused by errors and
hardware failures. If dat a is part ially corrupt ed or lost , OSS recovers t he dat a by using copies of t he
dat a.

Comparison between O SS and file systems
Comparison between O SS and file systems

Item

OSS

File system

Data model

OSS is a distributed object
storage service that stores data
as key-value pairs.

A file system uses a typical tree
structure for directory indexing.

Data retrieval

Objects are retrieved based on
unique object names (keys).

For example, the object name
test1/test.jpg does not
necessarily indicate that the
object is stored in a directory
named test1. In OSS,
test1/test.jpg is only a string.
test1/test.jpg is not essentially
different from example.jpg.
T herefore, similar amounts of
resources are consumed
regardless of which object you
access.

Advantages

OSS supports concurrent access
from a large number of users.

T o access a file named
test1/test.jpg, you must first
access the test1 directory and
then query the test.jpg file in this
directory.

T he file system supports
modifications on files, such as
modifying the content at a
specified offset location or
truncating the end of a file. It
also supports directory
operations such as rename,
delete, and move directories.

> Document  Version: 20220707

27

Product  Int roduct ion··Terms

Object  St orage Service

Item

OSS

File system

Objects stored in OSS cannot be
modified. A specific operation
must be called to append an
object. Generated objects are
different from objects uploaded
by using other methods. T o
modify an object, you must
upload the entire object again.

OSS can simulate features similar
to those of directories. However,
such operations consume a large
amount of resources. For
example, if you want to rename
the test1 directory to test2, OSS
must copy all objects whose
names start with test1/. T hen,
OSS creates objects whose
names start with test2/. T his
operation consumes a large
amount of resources. T herefore,
we recommend that you do not
perform such operations in OSS.

T he performance of the file
system is subject to the
performance of a single device.
More files and directories in the
file system consume greater
resources and take longer
processing time.

Disadvantages

We recommend t hat  you do not  map operat ions on OSS object s t o file syst ems because it  is inefficient .
If you mount  OSS as a file syst em, we recommend t hat  you perform only add, delet e, and read
operat ions on object s. You can t ake advant age of OSS t o process and st ore large amount s of
unst ruct ured dat a such as images, videos, and document s.

T he following t able describes t he differences in some t erms bet ween OSS and file syst ems.

OSS

Object

Bucket

Region

Endpoint

AccessKey

N/A

GetService

File system

file

home directory

N/A

N/A

N/A

multilevel directory

obtain the list of home directories

28

> Document  Version: 20220707

Object  St orage Service

Product  Int roduct ion··Terms

OSS

GetBucket

PutObject

AppendObject

GetObject

DeleteObject

N/A

File system

obtain the list of files

add a file

append data to an existing file

read a file

delete a file

modify file content

CopyObject (same destination and source objects)

modify file attributes

CopyObject (different destination and source
objects)

N/A

copy a file

rename a file

> Document  Version: 20220707

29

Product  Int roduct ion··Limit s

Object  St orage Service

7.Limits
7.Limits

T his t opic describes t he performance met rics and limit s of Object  St orage Service (OSS).

T he following t able describes t he performance met rics and limit s of OSS.

Item

Description

T he default bandwidth limit is 10 Gbit/s for regions inside the Chinese mainland
and 5 Gbit/s for regions outside the Chinese mainland. If this limit is reached,
requests are throttled.

No t e  When a request is throttled, the response to the request
No t e

contains the   x-oss-qos-delay-time: number   header in which

 number   indicates the duration over which the request is throttled. Unit:

ms. For upload requests, the exact duration over which a request is
throttled is returned. For download requests, the estimated duration over
which a request is throttled is returned. T he duration is estimated based on
the extent of throttling and the size of the downloaded objects.

If you require a higher bandwidth (10 Gbit/s to 100 Gbit/s) for your business such
as offline big data processing,contact technical support.

T he total QPS limit for a single account is 10,000. T he actual values are different
in different read and write modes:

Sequential read and write: 2,000

If you upload a large number of objects with sequential prefixes such as
timestamps and letters in the object names, many object indexes may be
stored in a single partition. In this case, if you send a large number of requests
to query these objects, the latency may increase. We recommend that you do
not upload a large number of objects that contain sequential prefixes in their
names. For more information about how to change sequential prefixes to
random prefixes, see OSS performance and scalability best practices.

Non-sequential read and write: 10,000

If you require a higher QPS,contact technical support.

You can use an Alibaba Cloud account to create up to 100 buckets in the same
region.

A bucket name must be globally unique within OSS. For more information
about the naming conventions of buckets, see Bucket naming conventions.

After a bucket is created, its name, region, storage class, and redundancy
type cannot be modified.

OSS does not impose limits on the capacity of a bucket.

Bandwidth

Queries per second
(QPS)

Bucket

30

> Document  Version: 20220707

Object  St orage Service

Product  Int roduct ion··Limit s

Item

Description

Object

T he size of the object that you want to upload

When you use simple upload, form upload, or append upload to upload a
single object, the object cannot exceed 5 GB in size.

When you use multipart upload to upload a single object, the object cannot
exceed 48.8 T B in size.

T he size of the object that you want to rename

You can rename only objects that are up to 1 GB in size in the OSS console. T o
rename objects that exceed 1 GB in size, we recommend that you use ossutil.

T he number of objects that you want to delete

You can delete up to 100 objects at a time in the OSS console.

You can delete up to 1,000 objects at a time when you use OSS SDKs,
ossbrowser, or ossutil.

W arning  Deleted objects cannot be recovered. Exercise caution
W arning

when you delete objects.

Whether existing objects are overwritten by objects with the same names

By default, when you upload an object that has the same name as an existing
object, the existing object is overwritten. T o prevent objects from being
accidentally overwritten, you can enable versioning for the bucket in which the
objects are stored. You can also include the x-oss-forbid-overwrite header in
upload requests and set the value of the header to true.

Data restoration

You must restore an Archive object or a Cold Archive object before you can
access the object.

It takes about a minute to restore an Archive object.

For a Cold Archive object, the restoration period varies based on the
restoration priority of the object.

Expedited: T he object is restored within one hour.

Standard: T he object is restored within 2 to 5 hours.

Bulk: T he object is restored within 5 to 12 hours.

For a domain name that is mapped to buckets located in regions inside the
Chinese mainland, you must apply for an ICP filing at the Ministry of Industry
and Information T echnology (MIIT ).

Custom domain name

Up to 100 domain names can be mapped to a bucket. However, a domain
name can be mapped only to a single bucket.

OSS does not impose limits on the number of domain names that can be
mapped to the buckets of an Alibaba Cloud account.

Lifecycle rules

You can configure up to 1,000 lifecycle rules for a bucket.

> Document  Version: 20220707

31

Product  Int roduct ion··Limit s

Object  St orage Service

Item

Description

Back-to-origin rules

You can configure up to 20 back-to-origin rules for a bucket.

In regions inside the Chinese mainland and the China (Hong Kong) region, the
default QPS for mirroring-based back-to-origin requests is 2,000, and the
default bandwidth is 2 Gbit/s. In regions outside China, the default QPS for
mirroring-based back-to-origin requests is 1,000, and the default bandwidth
is 1 Gbit/s.

Limits on images

Source images

Only JPG, PNG, BMP, GIF, WebP, and T IFF images are supported.

T he size of a source image cannot exceed 20 MB.

For the rotate operation on images, the height or width of the source
image cannot exceed 4,096 pixels. For other operations on images, the
width or height of the source image cannot exceed 30,000 pixels, and
the total number of pixels of the source image cannot exceed 250
million.

T he total number of pixels of a dynamic image, such as a GIF image, is
calculated by using the following formula:   Width × Height × Number

Image Processing (IMG)

of image frames  . T he total number of pixels of a static image, such

as a PNG image, is calculated by using the following formula:   Width ×

Height  .

Resized images

T he width or height of a resized image cannot exceed 16,384 pixels. T he
total number of pixels of the resized image cannot exceed 16,777,216.

Limits on image styles

You can create up to 50 image styles in each bucket. T o create more styles
for a bucket,contact technical support.

32

> Document  Version: 20220707

Object  St orage Service

Product  Int roduct ion··Limit s

Item

Description

Resource plans

Resource plans that you purchase for specific regions can be used to offset
the fees generated by the resource usage only within the specified regions.

You can use resource plans to offset the fees generated by the resource
usage in the regions that you specify when you purchase the resource plans.

You can purchase only one storage plan for each validity period. However, you
can upgrade the storage plan that you purchase. For more information about
how to upgrade a storage plan, see Overview.

You can purchase multiple transfer acceleration plans and back-to-origin
traffic plans within the same validity period to offset your fees. However,
these plans cannot be upgraded or renewed.

You can purchase multiple downstream traffic plans within the same validity
period to offset your fees. T hese plans can be renewed but cannot be
upgraded.

No resource plans are available to offset API operation calling fees, data
processing fees, and cross-region replication (CRR) traffic fees. You are
charged these fees on a pay-as-you-go basis. For more information, see API
fees, Data processing fees, and T raffic fees.

> Document  Version: 20220707

33