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66,560
Partition 500gb of database stored in SQL Server
I have 500GB of database stored in SQL Server. Because it has too big a database, it takes time to update and insert data. Now the case is that I want to partition the data. So which partitioning techniques should I use? Or is there any other technique which will improve my performance?
The performance issues aren't going to be with the database as a whole, they'll be with individual tables and queries. You want to identify what is slow first. Which tables, and why. Is it I/O related? If so, partitioning might not help if you are stuck on the same I/O subsystem. If it's page splits, then examine that ...
0
3
789
2009-09-18T06:23:17.003
api_errors
serverfault.com
516,189
VPN Failover Cisco ASA 5505
So basically we have a Cisco ASA 5505 (we have inherited this from a customer, none of us have any experience with Cisco's). Now essentially we have to WAN lines which we have setup in Failover, via adding Tracking ID to the main line. We set the Tracking ID to 1 and the SLA ID to 123, these were just random values we ...
Try the link below: https://supportforums.cisco.com/community/netpro/security/vpn/blog/2011/04/25/ipsec-vpn-redundancy-failover-over-redundant-isp-links This should cover all of what you want to do. Yes your remote side needs to be set up similarly in that it needs to understand what the primary and secondary IP addres...
2
1
1,324
2013-06-16T18:51:18.533
database_errors
serverfault.com
30,611
Fill ibdata1 With Zeros/Nulls/etc Or Change A Table's Tablespace
I have a MySQL 5.5 server running on CentOS 6. The MySQL package is a MySQL-released version (MySQL-server-5.5.28-1.el6.x86_64), not the stock CentOS one. I have moved an existing database over from a single tablespace to innodb_file_per_table. This leaves me with a 150GB ibdata1 file. The active space isn't a big deal...
There is absolutely no way to reduce the size of ibdata1 in-place. As for the already present data pages and index pages in ibdata1 from obsolete tables, you could let mysql overwrite them with transactions over time. RECOMMENDATION #1 You must migrate all data out and reload with an empty ibdata1. I have already addre...
1
2
2,516
2012-12-17T18:13:07.560
database_errors
dba.stackexchange.com
456,506
RewriteRule without using the domain name
I currently use a [CODE] to direct all traffic to a [CODE] file which then decides which page to serve. The current rule works fine and looks like this: [CODE] This means if I go to the following URL, the correct page will be displayed: [CODE] My problem: I'd like to be able to add the link [CODE] to my page which shou...
If you want [CODE] to display that long URL, then you should place the rule first (i.e. near the top of the file) and not use [CODE] . This way, [CODE] will rewrite it once, and then again when it hits your normal rule. The [CODE] means "this rule is last, if it matches, run with what I've just rewritten you to" which ...
0
0
524
2012-12-09T10:42:27.727
infrastructure
serverfault.com
999,337
shell scripting with expect and a complex command line: no such file or directory
I'm trying to make this work [CODE] But I always get: [CODE] What am I missing?
1) don't put the [CODE] arguments in quotes, and 2) spawn doesn't understand shell syntax, you need to explicitly spawn a shell [CODE] This uses braces, which are the expect/Tcl equivalent of shell's single quotes.
0
1
1,434
2020-01-17T09:01:31.523
infrastructure
serverfault.com
425,914
Why running migration turns into timeout in a production environment?
I know this is a theorical question since i don't have code to or any logs to show, but i hope that someone can give me some idea on this question. The problem in question was the following: On my work, on a deploy to a production system a migration took so much time running that it failed due to a timeout and this hap...
You will need to look at the sql generated for the migration to determine why it is slow. Possible reasons include: Deadlocks with other queries Rebuilding indexes Moving lots of data around Running out of memory due to large transaction This kind of thing wont show up on a small database, but can kill your production ...
-3
4
888
2021-04-29T21:16:30.277
api_errors
softwareengineering.stackexchange.com
979,529
Server issues with apache and payara
I am using apache as a proxy that redirects the traffic to a payara server. The issue I am experiencing is that when the server hits a traffic spike, it is slow to respond. I looked into our mpm_worker_module and here is the config: [CODE] The numbers here seem very exaggerated and very wrong. I am no expert on apache ...
The [CODE] value seems to be much too high. The apache documentation says: Special care must be taken when using this directive. If ServerLimit is set to a value much higher than necessary, extra, unused shared memory will be allocated. If both ServerLimit and MaxRequestWorkers are set to values higher than the system ...
1
0
131
2019-08-16T12:59:42.683
infrastructure
serverfault.com
282,645
How to find description of error in error log?
We have errors like these in our MySQL error log: [CODE] But I can't find anything about either MY-010211 nor error 203 in the documentation. Where can I find more information about this error, or other errors like this in general?
Errors labelled [MY-XXXXXX] are MySQL 8.0 errors. You can find the definition for this particular error here https://dev.mysql.com/doc/mysql-errors/8.0/en/server-error-reference.html#error_er_reading_table_failed .
0
0
113
2021-01-06T07:30:01.540
database_errors
dba.stackexchange.com
453,638
Plesk Postfix SMTP 550 5.7.1 "Command rejected" for one external sender
My server is rejecting emails from one external sender. I suspect this might be misconfiguration on the sending server, but I'm not sure from these error messages. The non-delivery report message the sender gets contains this text: [CODE] I also see this message in /var/messages at about the same time as the rejection ...
Don't know if you have the same issue as I had, but this fixed it for me: https://www.unixcafe.de/2012/04/e-mails-und-plesk/ With this command you change the default configuration of greylistings backlist filtering: /usr/local/psa/bin/grey_listing --update-server -domains-blacklist del:"dsl|pool|broadband|hsd" Plesk Sp...
1
2
15,394
2012-11-29T22:49:36.403
infrastructure
serverfault.com
937,900
What are the split latency measurements produced by httping?
I've been using httping to monitor the performance of my load balancer. The httping utility accepts a -S argument which is briefly described in the man page: -S Split measured latency in time to connect and time to exchange a request with the HTTP server. The output looks like this: connected to [hostname-snip]:80 (284...
I banged my head against this for a little while. I kept getting high values in the first field, and thought I was having trouble with the TCP connect phase. I ended up consulting the source code: From main.c [CODE] This indicates the output of httping -S is as follows: Time = [DNS Resolution Time] + [TCP Connect Time]...
0
0
198
2018-10-30T15:45:02.180
infrastructure
serverfault.com
213,963
Assigning Blame for Bugs versus Giving Rewards for Fixes
In a team that I used to work for, there was a policy that if you introduced a memory or other resource leak, you got a 'dummy of shame' hung on your door until you found the next resource leak. While it was effective at finding resource leaks, I felt like it placed more emphasis on blaming others rather than working t...
Your dummy of shame will actually result in your bugs getting fixed slower. People just being people, they will have a secret backlog of bugs so when they get passed the dummy, they will "miraculously" find another developers resource leak before the day is over. It's all about incentive, your policy does not promote f...
3
4
319
2013-10-10T03:08:30.073
data_quality
softwareengineering.stackexchange.com
352,747
Rate limiting (cutting off) if exceed n connections per minute
What do you suggest I use to rate limit incoming http connections (get/post) based on n connections per minute? If a particular client makes more than n connections in a given minute, drop all further connections until the minute is up. I currently use nginx and haproxy, but I'm really looking for the best tool for the...
It depends how gracefully you want to apply the cut off. For DROP/DENY on the TCP layer you can do it with iptables with something like: [CODE] You can target things to specific clients, with extra alternatives for the second rule e.g. [CODE]
2
4
1,591
2012-01-23T15:30:30.093
api_errors
serverfault.com
106,329
Cisco VPN endpoints disconnecting from a VLAN
I have a number of Cisco ASA 5505 and PIX 506e around the world acting as VPN endpoints. They connect to a Cisco VPN Concentrator 3000 at HQ. I am using Easy VPN to set up the VPN (i.e. most of the config is central on the VPN Concentrator) The majority of endpoints work absolutely fine. However, there are three that d...
I think you mean to say "subnet" every place you have "vlan". I don't think the vpn3k even supported assigning vpn tunnels to vlans. if you are using split-tunneling and pushing out 2 different routes for each of those subnets, then on the pix you end up with 1 ipsec security-association per subnet. It sounds like thes...
1
1
679
2010-01-26T09:07:44.720
pipeline_ops
serverfault.com
11,365
ERD via Chen's notation: How do I organize multiple 'last done' entries?
I'm having an issue creating a little practice ERD. I'm trying to do some more difficult stuff, and I'm not sure what the standard way to organize it is. Basically, I don't know which of these is most correct. Also, I'm trying to add some data: "Last video chat; last voice chat; last im; last email". Is [CODE] a better...
First, 'Friend' is probably not a different entity but just a relationship from 'User' to 'User' but your case may be special, I don't know. So about [CODE] , assuming a friend is just another user - yes. Additional info like 'last voice chat' & 'last im' shouldn't be part of a composite attribute, each 'last ' is mean...
4
4
1,935
2012-01-23T09:13:29.787
warehouse_errors
dba.stackexchange.com
11,495
About data cleansing, to what extent should we do our work?
As far as I know, when we deal with 'big data'. It is common we deal with more than 10 years' customers data. Quality issue is always there. What I am thinking about, to what extend we should deal with the data quality issues? A robust algorithm should tolerate with the data quality issues but if we do better data clea...
This is a question that is very dependent upon the data in question. Assuming that you can train your models in a reasonable time, I would start by not cleaning the data at all, and seeing how well your model performs, and then cleaning it a bit and redoing the experiment and so on. This is because it is possible to ov...
3
2
131
2016-04-29T04:19:50.950
data_quality
datascience.stackexchange.com
165,306
Block-level LUN replication options for Windows
When it comes to replicating a LUN or partition to a physically separate server, Linux has DRBD (now in the kernel!). As I understand it, it has both synchronous and asynchronous replication modes. When you have a fast network between your two servers, it can rock hard. I need to do the same thing for Windows servers. ...
Replication via the storage platform is pretty much always going to be the best bet. Granted the desire to move from one platform to another makes it a lot harder to do as most of the time you can only replicate from one array to another. Now if you are sticking with HP arrays they should be able to replicate between e...
8
1
4,246
2010-07-29T14:54:34.633
database_errors
serverfault.com
486,140
Stopping incoming spam with sendmail
I am having an issue due to a "smart" sysadmin that made some choices while I was away for two months: Spam. I manage probably close to 10,000 web/mail sites. He decided to allow all mail to everyone of those domains go to /dev/null if the user did not exist instead of bouncing it back. Which is OK in some cases but th...
I'm assuming that bandwidth is the problem you are facing and the solution you are looking for. Please correct me if there is a different problem. Is this all in one homogenous internal network or is it a bunch of independent sites/data centres? I'm wondering if it's feasible to run your own caching DNS resolver to cut...
0
1
1,650
2013-03-08T21:34:21.037
infrastructure
serverfault.com
229,695
MySQL (local) owner and permissions
I recently successfully installed the 64 bit version of mysql-5.5.8 on a MacBook Pro in the /usr/local directory. To address a completely unrelated software (RVM actually) , I chown-ed my /usr/local directory to $USER, Which made MySQL very unhappy. It complained specifically about the /usr/local/mysql/data directory, ...
MySQL by default witll run as the user specified by [CODE] , if at some point in the future you want to run mysql as your user you can change that on ´my.cnf´ by adding the following lines [CODE] Or if you want to add it as a startup option to mysqld or mysqld_safe [CODE] Also the default permissions for directories in...
3
9
19,384
2011-02-01T15:17:53.200
database_errors
serverfault.com
248,848
If the SIDs for ##certificate-based## SQL Server Logins don't match across replicas in an Availability Group, will this be a problem on failover?
I am reading mixed messages about server level object syncing between replicas in an Availability Group. As I understand it, server-level objects must be kept in sync (aside: then why isn't it part of AG by default?). For example, if a Login (identified by SID) does not exist on a Secondary replica (regardless of usern...
Is this of concern? Will a fail-over work despite these Logins having mismatching SIDs between some replicas? I don't think this is a concern with fail-over due to following facts: The fail-over basically targets user databases based on database mirroring endpoint CONNECT permissions on the ENDPOINT required to user de...
3
0
786
2019-09-16T06:44:49.230
database_errors
dba.stackexchange.com
68,116
Joining tables with one to many relationship
Hi I have a service ticketing system database (SQL Server 2008) which i want to get the hour elapsed for the tickets. One table contained the Ticket number and the created date/time while the other table contained the status log of each ticket. My problem is how to get the time elapsed considering the last update from ...
You can use a cte to get the latest change and then join it with the ticket table. [CODE] This results in: [CODE] If you need the time between changes you can extend the cte in this way: [CODE] That gives you the following output: [CODE] Please note that the [CODE] function is not available for the SQL Server 2008. Thi...
2
4
16,841
2014-06-12T09:12:08.393
database_errors
dba.stackexchange.com
133,518
Can we move SQL Server installed bit from default location to other drive
My client gave me command line installer for SQL Server. Since it is command line there is no option to select the installation path! So installer automatically chooses the default location [CODE] drive for installation. I would like to move all the installed bit from [CODE] drive to to other drive. Can I cut and paste...
The easiest method is (probably) to uninstall and this time run the command line installer again with a different set of flags and it will install to a different location unless you are talking about components not listed below. From: https://msdn.microsoft.com/en-us/library/ms144259.aspx Proper Use of Setup Parameters...
2
2
1,838
2016-03-28T08:57:39.530
database_errors
dba.stackexchange.com
15,133
Error: error loading plugins: loading plugin /data/ipfs/plugins/go-ds-s3.so: not built with cgo support
After cloning this repo run [CODE] (getting as output [CODE] ) run [CODE] make the appropriate changes in both [CODE] [CODE] and [CODE] , [CODE] I restarted ipfs [CODE] and then while checking that didn't have errors [CODE] then got Error: error loading plugins: loading plugin /data/ipfs/plugins/go-ds-s3.so: not built ...
After raising an issue in the GitHub of go-ds-s3 plugin , got to know from Stebalien that Ah, I see. At the moment, plugins only work on 64bit Linux for the pre-built binaries (because they're built on 64bit linux and building go-ipfs with CGO support for foreign architectures is tricky). For now, you'll have to build ...
0
0
138
2021-12-17T21:35:36.957
pipeline_ops
devops.stackexchange.com
420,834
How to improve the "truck factor" in my development team?
I'm currently a developer in a team of size 3-4 and I am concerned our team is not at all resilient to me taking days off or saying goodbye. Two years ago when I arrived at the company I made the choice to take over and learn the work of someone departing. We had also the team downsized due to the start of an other pro...
It's funny, because I've been struggling with this exact problem for years. At first I would do big pair programming sessions and give lots of personal attention. All that did was increase my burnout. People simply were not learning, and project management still had enormous expectations of the team. I kept trying to a...
5
8
445
2021-01-09T10:47:39.713
pipeline_ops
softwareengineering.stackexchange.com
282,398
MariaDB root password change using Ansible
I had tried to change MariaDB root password using following Ansible script. [CODE] In my [CODE] [CODE] As I was told password variable may not be taken, I added [CODE] step. [CODE] Similar issue discussed here . Thats where I got Password changing steps. This step runs without error, showing [CODE] , but yet I can acce...
Looks like your yaml is wrong ( [CODE] instead of [CODE] ). I'd study the docs for mysql_user ( [CODE] ) and check the examples to get an idea.
1
1
1,106
2020-12-31T11:40:08.233
database_errors
dba.stackexchange.com
894,301
Service Worker error with hosted site
I am having problems with a hosted site. It works locally. But ever since I added my ssl cert. I've been running into issue after issue. This most current one I can't seem to pinpoint where it's coming from. I have tried completely removing the service worker from my app and it still has the same issue. The specific er...
I figured this out by trying a few different things. I cleared my cache and that seemed to solve part of the problem. But then I noticed my redirect wasn't working as it should so I fixed the redirect with a conditional return of the redirect. [CODE]
0
0
711
2018-01-26T16:55:01.580
api_errors
serverfault.com
262,124
OOP CLI menu structure organization?
This problem has kept me from pursuing a project I'm working on because it influences the entire structure of the application. This question has been briefly touched on here , but I feel that it wasn't seen by many people and therefore wasn't very well answered. I'm working on an application in charge of navigating and...
First off, there is absolutely nothing about C++ which forces (or even encourages) you to use OOP. This is a common misunderstanding. Other languages lend themselves to OOP much better than C++, and while C++ supports OOP, it supports other paradigms much better. That said, your problem is classic, and lends itself wel...
3
2
3,639
2014-11-08T04:39:32.170
api_errors
softwareengineering.stackexchange.com
42,018
Large INSERTs performance optimization
I have 15 Amazon AWS EC2 t1.micro instances which simultaneously populate Amazon RDS MySQL d2.m2.xlarge database with data using large INSERTs (40000 rows in query). The queries are sent continuously. The table is INNODB, two INT columns, there is index for both columns. CPU utilization of RDS instance is about 30% dur...
Two hints for you: The [CODE] is redundant, because it is covered by the [CODE] [CODE] rows at a time might make for too large a transaction. Although these are very small rows (two [CODE] s) this may cause the transaction to go to disk, depending on your settings. I usually go with around [CODE] rows at a time (I go a...
0
2
3,846
2013-05-13T00:09:29.227
database_errors
dba.stackexchange.com
847,154
Ping latency vs location on a map (x kilometer of a trip) | ping-latency vs distance
Orange is having problem delivering the internet between biggest cities (I'm traveling via train). There are white spots on the way... They do not see the problem, so I thought - lets make a chart ping-latency vs distance (location on map) Do you know any tool that could provide this statistics? I have a Gobi 3000 GSM/...
The quick working solution with my GOBI 3000 GSM/GPS modem via: https://sigquit.wordpress.com/2012/03/29/enabling-gps-location-in-modemmanager/ My raw data (note that output is empty when there is no signal - that was my inital problem, since I was configuring at home :) ) [CODE] I need to write a script that would bot...
-4
0
475
2017-04-28T14:03:37.160
infrastructure
serverfault.com
871,053
Cpu pinning strategy for kvm / centos7
I am migrating from Xen to Kvm. In Xen I was able to easily pin host cpus to guest vms, and also to pin host cpus to the "dom0" . In Kvm I can also easily pin host cpus to guests vms, but, as far as I can I see, nothing prevents application running on the host OS to use these cpus. I want to prevent the case where a pr...
If I understand your question correctly what you want to achieve is to restrict the hypervisor so it can only use a single CPU/core (or a limited number) for it's own processes, interrupt handling and everything. And that all other cores can be assigned by libvirt to guest systems. Relatively simple is the [CODE] boot ...
3
5
9,803
2017-08-29T14:10:57.610
infrastructure
serverfault.com
34,719
Why won't IIS execute my custom 404 page? It tries to serve up the raw source code instead
I'm trying to configure Custom Errors in IIS6. I select the 404 error, set the dropdown to "URL," then enter this as the URL "/404.aspx" When go to: http://mysite.com/no-page-here It finds 404.aspx, but doesn't process it as a .Net page -- it tries to serve up the source as an XML file, then fails because it won't pars...
Do you have the correct extensions enabled in IIS6? In the IIS manager, go to Web Extensions (usually the last item in the left-hand navigation tree) and make sure that all the appropriate ones are enabled (usually .NET). Otherwise, this is exactly what will happen.
4
1
3,056
2009-07-01T21:14:45.397
infrastructure
serverfault.com
40,567
How to create a database for unknown kinds of data?
I am in the process of designing a database for a new PHP/MySql-based application. My problem is that I do not and cannot represent what should be saved in the database because it is unlimited and changing. Here is the problem example: The application will be a shopping website that has many kind of products all of the...
Unknown kinds of data sounds to me somewhat fishy. Your examples, of course, are all knowns. For goods and services careful analysis and normalization are important and I think you can get away from EAV modelling (which I think will cause mor problems than it solves) for core data. The rest could be stuffed in XML fiel...
7
10
3,405
2013-04-21T23:54:34.597
database_errors
dba.stackexchange.com
981,895
iptables send packet on blocked port using nat
I am trying [CODE] but there exists a rule to drop output on port 80. [CODE] To counter this, I tried to send curl request through port 8888, bypassing iptables output chain then creating a iptables nat rule [CODE] to change the destination port to 80 but I get [CODE] How can I send the query by bypassing rule AND not ...
I now had some time and tested it out [CODE] Downside is that it can only be don't to a single target IP address/port (destination match can be an entire subnet, but DNAT address has to be a single address) EDIT: I see. The Problem with our connection is that the output rule is one of the last stages in iptables, so it...
0
0
315
2019-09-04T17:13:24.447
infrastructure
serverfault.com
453,611
How to trigger killing of apache child processes on higher system load?
I'm having a Debian with WordPress on Apache, which gets pretty nasty spikes in load from time to time, leading to hanging on of the whole server. I've played a bit with some of the apache configuration parameters in order to make it a bit more stable, but the problems persists, although more rarely than before. What I...
Rather than blindly killing Apache processes, you should look at resource limiting them to avoid the spikes. Perhaps configuring limits via /etc/security/limits.conf (what it's called on RH type systems, not sure what the Debian equivalent is), using setrlimit, (or perhaps some other way of limiting the resource usage ...
1
2
740
2012-11-29T21:48:50.627
infrastructure
serverfault.com
98,683
SQL Server : parsing with XPath Performance
I have a UI that allows a user to select certain data points they want to filter the results by. There are things such as location, department etc. Once they have selected all of the options, I generate an XML string that I pass to my stored procedure. From there, for locations for example I create a temp table and dum...
When running the execution plan, I noticed that each one of the 5 or so queries that are parsing the filter data are costing about 12% which is over 60% of the query just to determine the data we are going to be filtering by. The query costs are based on estimates even in the actual execution plans. They do not tell yo...
4
5
4,884
2015-04-23T16:20:03.733
database_errors
dba.stackexchange.com
240,079
Redshift Spectrum CTE Union
I have a query with a CTE that uses a Spectrum table. When I try to union the CTE with itself: [CODE] I get the following error: [CODE] Is this a known issue and/or is there any way to work around it (that doesn't involve pasting the original query for every union)?
If this can be helpful to someone, as a workaround I've created a view instead of using CTE. [CODE]
2
3
1,335
2019-06-07T16:50:26.960
warehouse_errors
dba.stackexchange.com
277,775
How do I find out what's causing an access denied error?
I am getting an access denied error when I try to run a vbs script that uses WMI to do some stuff to IIS on Windows 7. Is there some sort of tool that can tell me what's causing the access denied?
Not 100% sure if it will work, but you could always try one of my favorite SysInternals tools called procmon (Process Monitor) Usually in strange permissions issues, I would run procmon, then launch/run whatever app is having issues. There are a lot of cool filtering techinques within ProcMon that should help you go th...
0
0
867
2011-06-07T10:05:16.697
infrastructure
serverfault.com
418,583
Multi-tenant system architecture to allow tenant specific and tenant agnostic data
How would you define the system architecture (mostly in terms of database structure) for a system which needs to have data available both at tenant level and organization level. An example of this is the following: A business is a client (let's say OAuth2 client) in the system. The business can have multiple subsidiari...
In our application we needed something similar, what we did was create an "organization units" table (that was the name in our case) and then each record may be linked to 0 or more OUs, if it is linked to at least one then it is visible only to users enabled to that OU, else it is visible to every user. This method imp...
0
2
462
2020-11-02T10:21:56.967
data_quality
softwareengineering.stackexchange.com
855,119
x2go session hangs if logging in using PBIS Open (Likewise Open)
I have x2go server installed on CentOS 7. I can create an x2go client session without any problems using a local system user account. The server also allows Active Directory logins via PBIS Open and I can ssh to the server using an Active Directory account. However, if I try to start an x2go session using an AD account...
Okay, so the PAM authentication failure was actually a red herring as the session was still authenticating okay. The problem turned out to be caused by the fact that we use numeric AD usernames which were being sanitized out by x2go when creating the session, hence it would hang. As per the advice from Martyn Welch her...
0
0
268
2017-06-11T11:48:35.623
api_errors
serverfault.com
866,398
Windows remote desktop goes blank on miminize
I have a few users that connect to my server via vnc and share the desktop to work together on a few things work related. I stay connected via remote desktop and they might continue working on our issues. When it is minimized, after a few seconds, the desktop on their side goes black. The only way that I can keep it fr...
This behaviour is by design. As you minimize your RDP session it won't receive a screen refresh. You could try to install a VNC server onto the server and enable multiple login as described in https://superuser.com/questions/887406/vnc-two-users-at-same-time . Multiple users can connect to a VNC server but that require...
2
1
240
2017-08-02T02:31:26.353
infrastructure
serverfault.com
778,798
Nginx reverse proxy in docker container - wrong IP logged
I am running Nginx in a Docker container as a reverse proxy using the configuration below. It basically redirects the request to another docker container running on the same machine Problem The problem is that the output in the access log states the wrong client IP address, specifically I get the IP of the Docker host ...
You probably will need the fix suggested by womble's answer in order to see the real IP at the real server. In order to see the real client IP at either the real server or the proxying node, though, you'll need to modify your Docker configuration. I think the issue stems from Docker's network firewall sitting in front ...
13
2
18,400
2016-05-24T20:24:13.947
pipeline_ops
serverfault.com
152,797
Check difference between results not listed and identify which day is the date
I have the following query: [CODE] It returns me: [CODE] As you can see in places marked with >>> there is no record that date, eg the date jumps 7 to 9 date and the date 14 jumps to 16, it ta correct because that day had no change. What do I need to know: How many ente day on 08 and 15 which are the days that has no m...
Check out my answer to the following question on StackOverflow https://stackoverflow.com/questions/3093924/select-all-months-within-given-date-span-including-the-ones-with-0-values/3111441#3111441 You could easily apply this method to your problem, and return data for all the days between a range, including those with ...
0
1
38
2016-10-19T20:09:18.163
warehouse_errors
dba.stackexchange.com
842,495
Print Ansible debug output without quotes/escapes
I need to know if there is a way to print information from an ansible playbook that doesn't cause ansible to automatically quote and escape the string. For instance, I'm using ansible to build a command that should be run separately from a different machine (ironic, i know, but necessary anyhow). Currently the output l...
You can either write your own stdout callback plugin or use some of this tricks: [CODE] Output: [CODE]
2
1
6,537
2017-04-04T13:54:18.707
pipeline_ops
serverfault.com
36,244
Unique Identifier with Extra Characters Still Matching in Select
We are using SQL Server 2012 with a unique identifier and we've noticed that when doing selects with additional characters added onto the end (so not 36 chars) it still returns a match to a UUID. For example: [CODE] returns the row with uuid [CODE] . But if you run: [CODE] it also returns the row with the uuid [CODE] ....
The implicit conversion also works if the value is enclosed in curly brackets [CODE] . If you add those in the query the implicit conversion will fail if the original value is too long because the last [CODE] ends up in the wrong place. [CODE] If you try the convert [CODE] you get [CODE]
18
10
10,261
2013-03-08T13:01:20.560
data_quality
dba.stackexchange.com
106,745
Why the server is not responding?
Our server occasionally refuses to serve a simple HTML page. This is happening during a relatively high number of requests. However, the processor is not heavy loaded and there are a lot of free memory. The error seems to occure 1 out of 50 requests in average, depending on the server load. I need to find the source of...
There is an interesting thing, in case the server fails to respond, the request string is not logged to access.log by Apache. This sounds like a network problem. The server should be logging any requests it receives even if it can't answer for some reason. You may want to verify that you aren't seeing packet loss on th...
0
3
7,253
2010-01-27T10:28:11.497
api_errors
serverfault.com
582,365
How do I accept two different types of network connections using iptables
I need to setup iptables for a mongodb database server, such that it allows only two types of INPUT connections: one connection to port 27017, monogdb's default port, from our main web-app one ssh connection from my main network, which has a different IP address from our web-app The issue is that these rules needs to b...
You're not allowing ESTABLISHED connections out from ssh. I'd go with a slightly simpler: [CODE]
1
3
150
2014-03-16T00:44:35.513
database_errors
serverfault.com
239,274
Why is my ASP.net MVC Site Not Serving Pages on Windows Server 2008?
Why is my ASP.net MVC site not serving pages on Windows Server 2008? The website is running under an application pool that has the .net framework 4.0 in integrated mode. It serves .htm files with no problem. When I try to view any of the MVC pages I get a page saying "Internet Explorer cannot display the webpage." Ther...
I found out what the problem was. This was a pain to track down. The server hosts 2 websites. The HTTPS bindings were not associated with the IP address for the website. Instead, the IP binding was set to "All unassigned". The solution was to associate the HTTPS binding with the website's IP address.
0
0
1,170
2011-02-23T17:02:45.360
infrastructure
serverfault.com
807,799
Core PowerShell commands missing when remoting into Exchange 2016 configuration
I'm running into an issue where simple commands (Get-Module, for example) are not present when remoting into an Exchange 2016 server. The command I'm running is: [CODE] The result is: [CODE] Other core commands, like Get-Command, work as expected - including Exchange commands (Get-Mailbox, etc). The only change I've ma...
Exchange servers were designed to be constrained endpoints. The session configuration [CODE] is a bare bones configuration schema with limited exposed methods. As Exchange servers are exposed to the outside world the designers are obsessed with security. The command you're trying to use is trivial in your existing cont...
4
1
789
2016-10-07T20:10:18.403
infrastructure
serverfault.com
262,283
Many to Many Link Table Return full chain from one record
I am looking to run a query on a many to many link table which chains records together and displays all the linked records. I've included a simplified data set for copy/paste as an example. I have a table of objects that include a code and a description which are linked to each other using a link table. I want to pass ...
Just to follow up with a solution, with thanks to Akina in the comments. I had to convert the above example to a proper table, and use the following select: [CODE]
0
0
125
2020-03-19T13:34:05.493
warehouse_errors
dba.stackexchange.com
637,971
SFTP for users (own site folder)
I'm trying to config SFTP, so that my users can access their own site folder (with PSFTP/FileZilla). I use Vagrant, CentOS7, NGINX and .sh file. This is my bootstrap.sh, for creating one of my users. [CODE] When I try to do normal SSH with Putty with user "vagrant" on 127.0.0.1, putty closes. I can't even enter a passw...
You should run [CODE] and try the sftp again while watching that. That will show you the errors from the sshd server that aren't allowing this sftp access. From looking at the steps you performed, after you set the ownership of $JS_WWW to jeroensteen:sftpusers, you change it to nginx:nginx. Did you perhaps mean to set ...
1
0
297
2014-10-18T09:23:43.543
infrastructure
serverfault.com
806,472
Godaddy dedicated server randomly timeout users on just 400-500 Active users
We have Godaddy's Dedicated server. but we are facing problems with this server. after on 400-500 active users server randomly timeout or kill users. we this it's error with IIS. We did conversation with some server experts they said there is some issue with IIS. but nobody can resolve this issue. i share a screen shoo...
Install monitoring then repeat as necessary Gather data Analyse data Make changes based on analysis Monitor effect of changes This isn't rocket science but there's no reason why you can't use Scientific Method .
-3
3
108
2016-10-01T04:38:19.327
api_errors
serverfault.com
1,003,089
GCP Kubernetes engine - crash of nginx-ingress-controller after large file upload
I'm trying luck here to solve my problem happening on Google Cloud Kubernetes Engine. Problem in short: When I upload file via my PHP application of 15-20MB, nginx ingress controller crashes, disk IO goes rapidly UP, then CPU goes up and takes about 5-30 minut until IO and CPU goes down and all sucessfully restarts. He...
Looks like I've solved the problem. Nginx-ingress included also modsecurity (WAF) which had enabled many rules. After disabling of modsecurity huge logs has gone and until now it seems it works. Now I can successfully upload 20 times 30MB files at single time without any issue in logs and any disk I/O. I will update th...
2
1
2,954
2020-02-14T14:18:53.993
pipeline_ops
serverfault.com
549,693
Wrong php_sufix config variable in MAMP
I've just installed MAMP and I'm trying to install the Mongo extension via [CODE] but I'm getting an error: [CODE] I'm not sure what's going on here. My pecl directory is: [CODE] PHP version is [CODE] I downloaded the latest version of PHP into the following directory and ran [CODE] as MAMP doesn't come with all module...
Your actual issue is that pecl can't find autoconf: Cannot find autoconf. Please check your autoconf installation and the $PHP_AUTOCONF environment variable. Then, rerun this script. Try searching on that basis and you should find what you need - it seems that at least once person has just compiled and installed autoco...
0
3
1,638
2013-10-30T16:52:06.543
database_errors
serverfault.com
211,500
What is the downside of returning a string instead of a void function or throwing an exception?
Say I have a method that inserts a record into the database. I don't need to know the newly-inserted ID or anything else. I have two options: [CODE] [CODE] In the first: if an insert is successful, the calling code will continue. If it fails, an exception with the details will be returned and the calling code will hand...
IMO the void method is preferred. In OO programming it is better style to simply use objects and if there is an error throw an exception which can be caught. The exception thrown should be pertinent to the error and descriptive - the descriptive message may not be shown to the user but logged, depending on the scenario...
1
6
118
2013-09-13T19:35:37.703
api_errors
softwareengineering.stackexchange.com
1,077,204
nftables loopback connections not working in CentOS 7
I have removed [CODE] and installed [CODE] in CentOS 7 (kernel [CODE] ). My ruleset is as follows: [CODE] I have uninstalled [CODE] completely and don't have any [CODE] rule. But this [CODE] configuration does not allow [CODE] connection, even [CODE] gets timeout. Other things (e.g. [CODE] , [CODE] port-forwarding etc....
I figured it out! Problem was the unconditional [CODE] rule. I replaced [CODE] with [CODE] and the problem solved!
0
0
865
2021-09-10T16:02:54.957
infrastructure
serverfault.com
156,811
mongoDB in micro-services structure
I'm building a game that have micro-services structure using docker. The way i started to build my services is having a mongoDB instance to each service, so having OneToOne service to mongoDB instance, [CODE] This really made sense at the beginning as those services for example have nothing in common and don't need hav...
It's sensible to think about how to scale your application in future, but you can start with a simpler deployment that can grow with your requirements. what should i choose? having 1 database sounds good as it will save me a lot of resources and will make my life easier, but separating the services to many database sou...
7
6
2,562
2016-11-30T19:16:28.287
database_errors
dba.stackexchange.com
321,174
What I make wrong and Cannot inset a value at sqlite3 using custom trigger?
I am making the follwing table at SQLITE3: [CODE] And in order to test the trigger I do the following: [CODE] But I get the error: [CODE] Any ideas about the syntax error? What did I mess up?
Any ideas about the syntax error? What did I mess up? 1.Wrong quotes used [CODE] 2.The trigger. I need to remove both http and https. From the docs The value of NEW.rowid is undefined in a BEFORE INSERT trigger in which the rowid is not explicitly set to an integer. Because of the behaviors described above, programmers...
0
0
58
2022-12-19T21:23:54.460
warehouse_errors
dba.stackexchange.com
51,293
calculate days and equally distribute remaining
I'm having difficulty with calculating remaining days from hours being distributed over a date range within a given time period. For this example, the time period would be 2013-11-01 through 2013-05-01 (it will always be a 6 month period). The [CODE] table has a 30 year set. 1 Value of [CODE] for [CODE] indicates Monda...
hope this works for you. It meets your expected results I believe: [CODE] I did this is here http://sqlfiddle.com/#!3/682ff/42 , but I also simulated your calendar table witha CTE so the code there is a bit messier.
6
2
1,635
2013-10-09T20:37:01.217
warehouse_errors
dba.stackexchange.com
170,430
MySQL server tweaks
My server has... [CODE] I'm wondering if I should change any memory settings for MySQL. Currently there is no limit on MySQL connections... the settings are all default.
I would highly recommend you check out http://www.day32.com/MySQL/ and http://blog.mysqltuner.com/ who both provide scripts that can help you analyze and perform some basic tweaking to MySQL.
0
4
158
2010-08-14T02:49:55.973
database_errors
serverfault.com
251,508
Migrating production CentOS server to a VirtualBox VM?
I want to migrate a production server to a VM for development purposes, and exactly duplicate the production environment as closely as possible. The production server is running CentOS with a single ~3TB partition on a RAID 5 array. Although only 13 GB is used, partimage is not an option because the machine hosting the...
You can convert your physical machine to virtual using VMware converter . The resulting vmdk file can then be used directly by VirtualBox. In VirtualBox during the [CODE] process, when you get to the [CODE] dialogue select [CODE] and then browse to the location of your vmdk file.
1
1
3,955
2011-03-24T18:53:27.087
database_errors
serverfault.com
221,004
Optimization of a query on a table that represents a weak entity type
I've been trying to figure this problem out for a while now, so I decided I'll try my luck here. I have a very complex online shop DB structure (multiple shops in one database, hundreds of thousands of products) and I'm querying MySQL to return products from a specified category. Products are in a many-to-many (M:N) re...
[CODE] .. [CODE] . If you don't want products without images, then [CODE] and leave out the [CODE] criteria. Same with [CODE] , if you want a not-null category in the [CODE] , don't use a [CODE] , [CODE] is what you are really requesting. Ordering with [CODE] is probably also a cause of slowness. Your subqueries on [CO...
3
2
177
2018-10-25T15:12:14.997
database_errors
dba.stackexchange.com
133,488
Common diagnostics which VisualVM is used for
There's a lot of documentation out there on how to use the 'jvisualvm' profiler, but very little (if any) real-life advice on how to analyze all those charts and dumps. I'm just a little overwhelmed by all the graphs and having trouble making sense of it all. I know this is sort of a monolithic-type question, but there...
What specifically are some of the common analyses for VisualVM? I think these are the same as for any other Java profiler. For example, YourKit profiler demos page currently lists the following "most popular" analyses: CPU profiling J2EE profiling Finding a memory leak Profiling excessive garbage allocations
2
1
251
2012-02-06T01:34:06.663
pipeline_ops
softwareengineering.stackexchange.com
896,223
rsyslogd - how to discard repeats of alarm "X" unless alarm "Y" happens in-between (preserve context)
I have an interface which when disconnected spits out alarms every 60 seconds. [CODE] My rsyslogd is spamming the downstream SNMP agents. To avoid that, I want to send only on alarm when the connection goes DOWN. Easy enough you might say, just use action.execOnlyOnceEveryInterval. But the trick is that once the connec...
If you are using 7.5.6 or later, you can use mmsequence as follows. [CODE] Note that mmsequence is marked as "deprecated" in rsyslog v8. The documentation states that you should use "global variables" instead. However, searching the documentation for global variables gives no information about how you can use these myt...
0
0
69
2018-02-08T01:50:27.497
infrastructure
serverfault.com
361,134
Nginx includes config files not in order?
Is the order in which Nginx includes configuration files fixed, or random? Apache explicitly states wildcard characters are expanded in alphabetical order. With Nginx it seems this does not apply, and the manual says nothing about it . In my setup, [CODE] was included before [CODE] , which defeats my purpose of definin...
According to nginx source code it uses glob() function with GLOB_NOSORT parameter , so, the order of file inclusion could not be clearly established. This was changed in November 2012 , first released in 1.3.10. From the changefile : now if the "include" directive with mask is used on Unix systems, included files are s...
19
29
13,788
2012-02-17T09:45:18.307
infrastructure
serverfault.com
151,469
Why is the query_hash zero for EXEC statements?
I'm setting up a monitoring system for SQL Server using Extended Events to find heavy queries as 'production feedback' for our developers. I'm using the events [CODE] and [CODE] , with predicate filters on cpu_time, logical reads, etc. I was hoping to aggregate the results on [CODE] and [CODE] like demonstrated in nume...
To explain why the hash is created: When we submit a query to the server, the algebrizer (yes that's what it is called) process creates a hash, like a coded signature, of the query. The hash is a unique identifier. An identifier is unique for any given query, including all the text that defines the query, including spa...
8
1
678
2016-10-05T11:35:55.337
pipeline_ops
dba.stackexchange.com
393,618
Exchange 2010 and Exchange ActiveSync
I have been asked to set-up a test Exchange Server 2010 machine in order to test the Exchange ActiveSync system as an alternative to our existing Blackberry mobile email solution. We intend on using Windows 7 phones to hook into our Exchange system. I have installed the server and installed a commercial SSL certificate...
Try the following in the Exchange Management Shell: [CODE] Where [CODE] is your server name. Or Navigate to [CODE] > [CODE] > [CODE] > [CODE] > [CODE] (Default Web Site) > [CODE] . Make sure that [CODE] is set to [CODE] . Make sure that [CODE] is set to [CODE] .
0
1
2,975
2012-05-29T14:59:44.920
api_errors
serverfault.com
997,064
Routed IPv6 range and WAN IPv6 range in different subnets
I have a datasheet from my ISP stating a "WAN IPv6 Range" and a "Routed IPv6 Range". When I configure my IPv6 on my router I use a static IPv6 configuration with my WAN range and get a successful connection and it works. I also enter the routed range in the configuration, but it does not show up in neither my local LAN...
You divide the [CODE] range into standard [CODE] networks for use on your LAN networks (you have 65,536 [CODE] networks you can derive from the [CODE] network). The WAN [CODE] network should be used on your router WAN interface, and the [CODE] networks derived from your [CODE] LAN block should be assigned to your route...
1
2
899
2019-12-30T02:58:40.183
infrastructure
serverfault.com
67,001
classification imbalance data - bias and class weight
This page shows a classification problem. They have used bias as well as bias along with class weights. What is difference between bias and weights? In some other techniques such as Random Forest we could adjust cut off from 50% to say 90% so that if the edge node has 90% examples of high density class then only it wil...
Normally the bias is "part" of the weights, and for this particular algorithm or model, the bias is a way to use to help solve unbalanced data issues. For fraud detection, the rate of event data is really rare, here event is the transaction is a fraud. In this so-called machine learning model, the whole tutorial was do...
3
2
1,249
2020-01-24T17:15:28.623
data_quality
datascience.stackexchange.com
297,360
Configure LeftHand iSCSI SAN for jumbo frames after clients are configured
This is similar to enabling jumbo frames on an iSCSI network after the fact but in our case we configured the switches and then went through all the hosts, enabling jumbo frames (we may have screwed ourselves here). The SAN is a Lefthand (actually 2 SANs mirrored). So the plan is to configure one of the SANs for jumbo ...
Answering my own question here in the hopes it will help others. We did this today and I have to say the pucker factor was pretty high:) Changing the first SAN to jumbo had no problems at all. When we broke the MPIO on the second SAN all the hosts got very angry (stopped responding) and it took about a minute for them ...
1
0
1,037
2011-08-03T23:28:08.837
database_errors
serverfault.com
353,951
Restarting the httpd service in RHEL returns "Stopping httpd: [FAILED]" - How do I fix this?
This is my first indication of an issue: [CODE] I know httpd is running [CODE] and it is using ports 80 and 443 [CODE] so I assume that I get the message "no listening sockets available" because httpd cannot stop to release ports 80 and 443. I am using RHEL version 5.7: [CODE] I can see a bunch of processes running for...
The stop function in /etc/init.d/httpd uses the pidfile: [CODE] Possibly, the pidfile [CODE] is out of date or missing (could you have started httpd in the past without using the [CODE] script or [CODE] ?). You can check that file (and its contents) with your [CODE] . Meh, just [CODE] . Then start the service up as you...
6
5
29,374
2012-01-26T17:27:24.893
infrastructure
serverfault.com
219,720
Performance Tuning ETL
I administer a datawarehouse running on SQL Server 2016. This datawarehouse has most of its ETL processing done during a nightly load, except for a few SSIS packages that run throughout the day, then SSAS processing done afterward, so when I arrive in the morning, there's no active monitoring I can perform. The process...
For SSIS you can implement logging on the packages. A good place to start looking would be at the [CODE] and [CODE] steps of the components within the packages. The [CODE] event will be useful to check for these steps, as it records the time spent in each of them. You can read more about logging for SSIS here . For SSA...
1
2
371
2018-10-10T03:15:54.873
pipeline_ops
dba.stackexchange.com
401,433
Is injecting user input dependency class to menu class appropriate?
I am currently designing classes for the User Interface (UI) of my application. When defining the interface of a class [CODE] I faced a design decision of whether I should inject the user input as a dependency. My Current Implementation [CODE] is responsible for selecting and maintaing the state of one of the tabs in t...
In the general case, if it wouldn't be about user input, the first approach is not necessarily bad: You inject an object at construction, You observe the injected object And you react on the observed object's change of state If done properly, you have the desired behavior, and loose coupling. But in the context of your...
0
2
179
2019-11-22T00:03:02.587
api_errors
softwareengineering.stackexchange.com
1,102,916
Is there a way to programatically determine whether a Windows computer is AAD joined as SYSTEM?
I would like to be able to determine via script whether a given Windows workstation is AAD joined, Hybrid AD joined, or on-prem AD joined. I would like to run this script from the RMM I'm using so I can store those results in the RMM and be able to easily group computers into those three categories (plus one for workst...
Query the registry https://nerdymishka.com/articles/azure-ad-domain-join-registry-keys/ Determine if a machine is joined to AzureAd HKLM:/SYSTEM/CurrentControlSet/Control/CloudDomainJoin/JoinInfo/{Guid} Underneath the key, the following keys can be found: – TenantId – UserEmail [CODE]
6
7
3,274
2022-06-09T17:21:19.400
infrastructure
serverfault.com
673,474
Emails from my domain getting blocked at all other domains
Recently I tried to set up a new email server using iRedMail on Lubuntu. The mail server workes very well when email conversation is in the same domain. But when a user tries to send email to some of the most popular domains like gmail, hotmail or yahoo; all the emails are blocked. I tried to send an email to my gmail ...
Sorry for the mess. The problem was in other configurations of my main.cf file. It would have much easier for you guys if had posted that part. Still thank you all of you guys. The value for smtpd_sasl_local_domain = was not set. Hence the postfix was not using the smtp authentication. The new values are smtpd_sasl_loc...
-2
0
1,089
2015-03-06T11:50:10.737
api_errors
serverfault.com
401,983
Resize base XenServer 6.0 partition
I've extended my hardware RAID device on LSI MegaRAID controller by adding disks to the array. While making Linux notice the block device size change was not straight forward, I've found that one can rescan the device (using [CODE] in my case, for first logical drive) to fix that. Unfortunately, I'm stuck at this point...
An hour of googling was 5 minutes short to find the answer... anyway: [CODE] and [CODE] allow to relocate the second GPT header in "expert mode". If the basic situation was like this: [CODE] (note the [CODE] ) By using the [CODE] command in [CODE] and then [CODE] command, the partition table looks like this: [CODE] (no...
2
3
11,532
2012-06-25T12:05:08.947
infrastructure
serverfault.com
41,115
Storing no of players the last seven days in an online game
I want to plot the number of players, in the last seven days, of an MMORPG which haves 50~ servers. The system fetches the number of players in each server every 15 minutes and I'm not really sure how to store and update this information in an efficient way. The easiest (but probably not so efficient) way I can think o...
I would store the timestamp, server identifier, and number of players in just the way you thought of, deleting the oldest (if you need to) and adding new ones every 15 minutes. Moving the server names into another "server" table and referencing the primary key in your player count table would be a more conventional nor...
0
3
57
2013-04-28T17:48:50.133
warehouse_errors
dba.stackexchange.com
306,120
ORA-00257 even when Oracle is in NOARCHIVELOG mode
One of my jUnit tests fails with the following exception: java.sql.SQLException: ORA-00257: archiver error. Connect internal only, until freed. The Oracle error code refers to (for lack of better words/knowledge) [CODE] mode related issue. But, I made sure that the DB is running in [CODE] mode. I checked [CODE] E table...
This happens when the archiver cannot write or has no space in the destination specified by log_archive_dest. Check the results of "archive log list"
0
0
912
2011-08-29T14:43:26.673
hadoop_errors
serverfault.com
49,741
How to make a great functional specification
I am going to start a little side project very soon, but this time i want to do not just the little UML domain model and case diagrams i often do before programming, i thought about making a full functional specification. Is there anybody that has experience writing functional specifications that could recommend me wha...
What you suggest is fine from the point of view of the Systems Engineering purists. (There will be a few Agile devotees who think its all way overt the top... and you should just get out and do stuff with the usual reviews, etc). However, you need to take into account what you are doing, and who you are doing it for. D...
9
23
5,196
2011-02-19T23:42:08.983
api_errors
softwareengineering.stackexchange.com
286,601
Cisco 877 VPN: PPTP encryption not working
A followup to this question . I have a Cisco 877 ADSL router configured (at last!) to act as a VPN server; it supports both PPTP and L2TP VPNs, and I can successfully connect to it from Windows computers using the built-in VPN software. There is only one problem: when using a PPTP VPN, encryption doesn't work. If I con...
Looks like it was a bug. I updated the router's IOS from version 15.0(1) to 15.1(3) and now the problem is gone.
1
0
2,152
2011-07-03T17:40:16.193
infrastructure
serverfault.com
577,026
FC14 and yum dependancies
I've got my hands on an FC14 machine and I've been trying to get yum working on it over the past couple of days. The machine (which is an appliance) shipped with a conflicting package to fedora-release and has taken a few days to get yum running on it. I've got yum working now but am getting a whole host of dependancy ...
Fedora 14 is now unsupported. You can't install or use repositories because since it is unsupported. There are no more repos and updates for Fedora 14. You have three options: upgrade to the newest Fedora, migrate to CentOS, or try to compile what you need (I think the last way is a dead end). The Fedora project only s...
1
3
53
2014-02-20T11:21:36.970
infrastructure
serverfault.com
263,451
mod_rewrite rules in a separate configuration file (Aegir)
I got a virtual host configuration file I cannot edit or modify directly, since it's generated by our hosting platform, Aegir . But it does have [CODE] and [CODE] statements that are included before and after the vhost-configuration. What I'd like to do, is to add vhost-specific rewrite-rules in separate files, so they...
Without knowing the details of your hosting environment, I can't give you a definite answer to your question. However, I am thinking you might find a solution to your problem on Apache's Mass Virtual Hosting page. If I am understanding your problem correctly, and I hope I am, you might be able to do something similar t...
1
0
1,182
2011-04-26T11:37:33.750
infrastructure
serverfault.com
8,048
Is maintaining a single database an issue when the underlying project becomes larger?
I have seen this related post but it was more focusing on the amount of consumers for the databases, which is not my only problem. I have a situation, where I am taking part of the design of a new data model implying a lot of relationships across tables and where different users would not be allowed to access all the d...
I think you are correct in your answers and JNK is correct about locks. I see some reasons to have multiple databases. Replication. If parts of your database should be replicated to local read servers they benefit from being on different database. I don't know about sql-server specifically but in mysql (and generally) ...
1
2
199
2011-11-17T16:57:59.737
database_errors
dba.stackexchange.com
560,509
Nginx with ssl always returning 301
I am trying to setup nginx with ssl, to serve some static HTML and the output of some Python scripts (through uwsgi). It works fine with HTTP, but I am not able to make it run on HTTPS, as nginx is returning a "301 Moved Permanently" matter the URI (i.e., even for those that do not exist). I am currently using a self-s...
Your rewrite rule is in the wrong place : it applies (only) to the server block which does SSL already. Your browser might have been already complaining about a never-ending redirect. Put the rewrite rule in the server block which listens on Port 80, without SSL.
1
1
1,480
2013-12-10T21:35:33.037
infrastructure
serverfault.com
60,383
In Oracle AWR report how to use "Latch statistics" section in analysis
Latch statistics in AWR report contain following sections [CODE] How can I use these sections of AWR report for useful insights to improve Oracle performance?
Usually, latches are used to optimize SQL. Latches are what provide concurrent access to Oracle's internals. You always want a high hit ratio, although occasionally a high hit ratio isn't indicative of everything running well. Always see if latch "latch free" is in your top wait events: if it is, you might want to look...
2
0
3,474
2014-03-07T08:04:56.757
database_errors
dba.stackexchange.com
132,259
TSQL Script Execution Through Power shell, Special Characters Rendering Problem
We have a simple T-SQL script file (.sql), which we execute through Powershell. Everything works fine, except the script portion, where we are using some special characters as string (example: 'ô' ). The same script works fine, if I just execute it through SQL Server Management Studio, but through Powershell it's not r...
This issue has nothing to do with SQL Server Collations. The problem happens (i.e. the characters get transformed) prior to connecting to SQL Server. If the problem could be resolved by prefixing the string with an upper-case "N", then the script wouldn't work correctly in SSMS (as the OP states it does). The problem h...
3
2
1,392
2016-03-15T09:50:41.690
database_errors
dba.stackexchange.com
1,014,317
Ubuntu 14 Virtual host file not working with IP (e.g. 123.123.123.123/supervisor2)
I have a virtual host file /etc/apache2/sites-available/supervisor2.conf : [CODE] I have added the website via: a2ensite supervisor2 I have confirmed that /var/www/supervisor2 exists, and I want to access it via " 123.123.123.123/supervisor2 " but I get: Not Found The requested URL /supervisor2 was not found on this se...
There is no mention of "supervisor2" in your configuration. Don't forget to restart Apache after correction.
0
0
27
2020-04-27T01:12:17.270
infrastructure
serverfault.com
786,118
Large CPU spike for proc (www-data)
I am trying to understand what is causing these routine high CPU loads on my server. The server is using serverpilot on a small Digital Ocean Droplet which comfortable runs a few wordpress sites with very low traffic. Over the last two weeks I have seen (at the same time on a Friday) a process that triggers the followi...
You (or someone on your behalf) will need to use Scientific Method or similar to determine the cause. You are already partly on your way in as much as you have defined the problem A large CPU spike and have some data to work with. You will need to review the data you have. Analyse your logs and if necessary gather more...
0
1
361
2016-06-24T17:27:06.567
infrastructure
serverfault.com
28,018
Can't start postgres server, SHMMAX too small
When I try to start the postgres server with [CODE] I get this error: Starting PostgreSQL 8.4 database server: mainThe PostgreSQL server failed to start. Please check the log output: 2012-10-31 17:52:46 EDT FATAL: could not create shared memory segment: Invalid argument 2012-10-31 17:52:46 EDT DETAIL: Failed system cal...
This question has been asked many times. Try a search. Or Google. This chapter of the manual deals with it comprehensively.
1
2
2,284
2012-10-31T22:50:51.837
database_errors
dba.stackexchange.com
382,350
Can I produce a deadlock with a single thread? aka. What is a deadlock?
This expands on " Deadlock in Single threaded application " on StackOverflow . That question was not really conclusive and I think it better belongs here. By the definition of a deadlock, is it technically possible to produce a deadlock by using just a single thread? This is the definition of a deadlock according to Wi...
"Deadlock" just means you have two actions that are each locking each other so that neither can proceed. Obviously in order to have two things running at the same time you would normally need more than one "thread". But a thread is just an abstract layer over the actual CPU. You can easily* write you own abstraction la...
1
4
6,057
2018-12-02T21:09:29.490
database_errors
softwareengineering.stackexchange.com
432,737
What does "alloca" stand for?
The [CODE] function allocates memory in the stack frame of the caller. What did [CODE] originally stand for? Are there any sources regarding the etymology of the name?
I did some sleuthing in historic sources, and it seems that the "a" in "alloca" stands for "automatic", as in automatically freed. The GNU man page says: [CODE] Linked from this commit message I found archives of UNIX/32V and PWB/UNIX sources, each of which contains an [CODE] assembly file: [CODE] [CODE] [CODE] [CODE] ...
3
8
451
2021-10-15T16:45:49.903
api_errors
softwareengineering.stackexchange.com
1,038,744
Mikrotik hotspot issue - login page not loading
I've configured a hotspot on a Mikrotik CCR1036-12G (OS 6.47.4), but after the device connects to the wifi and asks to authenticate in the network, the login page remains loading for a while and returns an error page with [CODE] . The hotspot worked perfectly already, but suddently stopped.
Solved! The problem wasn't on Mikrotik configuration, that was OK. The problem was on the wifi configuration, in Unifi solution: i) In the network configuration, the used network was marked as "Guest". I changed to "corporate". ii) In the wireless configuration, there was enabled the "Gest Policy" option. I disabled it...
0
0
1,599
2020-10-14T19:08:57.513
infrastructure
serverfault.com
52,498
How to include Innodb_trx_id in MySQL slow log
Evaluating MySQL's slow query log with pt-query-digest from the Percona Toolkit, I need to group queries by transaction. As it seems, the easiest way to do this is to group by the Innodb_trx_id attribute. However, my logs don't include this attribute. I tried with vanilla MySQL, MariaDB and Percona Server -- so I figur...
The extended fields that Percona added are not available in stock MySQL. The only other option is to add a comment to your SQL query in your app. The comments are added to the log, and pt-query-digest can parse fields out of comments with the [CODE] option. It's a bit tricky to discover the transaction id. You can quer...
2
4
886
2013-10-30T12:48:37.307
database_errors
dba.stackexchange.com
219,776
How to setup a tunneled connection to a NAS?
While looking into alternatives for Dropbox I explored the idea of a NAS. It would be easy to hook up the NAS to a broadband connection and have the users access the files. However, - The data needs to be encrypted on the NAS itself (in case it gets stolen). - The connection to the NAS needs to be secure (VPN?). - The ...
You may have a look at ... http://beginlinux.com/blog/2009/01/create-an-encrypted-samba-share/
0
0
250
2011-01-07T10:34:42.837
infrastructure
serverfault.com
68,196
Problems with system standby in ubuntu
I can't put my Ubuntu (9.04) in Standby mode. When I try to do so, it appears to do something and then turns the screen off. However, the fans remain on and by measuring the amount of electricity it uses it doesn't seem to be actually asleep. At that point, I can't really wake it up either - pressing keyboard keys, cli...
/bin/tail /var/log/dmesg.0 after this happens and return with result.
3
1
553
2009-09-23T21:56:10.467
infrastructure
serverfault.com
157,104
How do I export my web-host's (VPS) filesystem to an image to load locally in a VM?
I'm a dev new to sysadmin, armed with root access to a linux box. I want to practice a bit on the configuration in a local virtual machine. What setup would I need to do this? My current idea is: Export server file system as an image Transfer image to local system Load image on a vm Play. Deploy I suspect I'm missing s...
May or may not work, but you could try installing the basic OS on your local vm, then load a LiveCD and use rsync on the remote machine to sync the entire remote root to the root on the local machine.
0
0
466
2010-07-02T18:19:53.383
infrastructure
serverfault.com
546,914
Fedora, fsck fails at boot
I'm facing a problem in my server during the startup. This is my actual configuration: [CODE] This are the actual errors i got: [CODE] Then, i can press CTRL+D and system got rebooted, or enter root password and be dropped to a shell with this prompt -> "(Repair filesystem) 1:" With the /dev/md126 AKA /dev/md1 there is...
You need to fix your [CODE] . While it contains entries telling the OS that it should find and mount [CODE] and [CODE] on boot, the OS won't be happy. Either boot from rescue media and modify the entry, or boot, fix the root filesystem, do [CODE] and modify the entry. Once that [CODE] entry says [CODE] in place of [COD...
0
2
3,167
2013-10-18T07:40:47.700
infrastructure
serverfault.com
1,072,976
Angular server side rendering keeps going down to 502 errors
So I have been running my front end on the server for a few weeks now(angular Server Side rendering). I keep running into this issue where the front end goes down to a 502 error. I have to restart the server ever few hours to ensure that it is back up. The traffic is not crazy and everything seems to be fine(in my cons...
HTTP 502 typically means that one server (the one originating the HTTP 502 response) tried to talk to another server and failed. You mention that rebooting the "first" server (the one eventually handing out the 502) fixes the issue, which probably means there's some kind of non-persistent problem on that server. Possib...
2
1
2,869
2021-07-29T07:38:17.167
infrastructure
serverfault.com
792,141
Amazon Web Services Elastic Load Balancing No Downtime
I'm trying to figure out how Amazon Web Services Elastic Load Balancing would create no downtime. Elastic Load Balancing pings your server path every so often (normally a couple of seconds). If it doesn't receive a response within a set period of time (normally a second or two) it will take the server offline and not s...
There is conflicting information about this online. Some resources say ELB retries a request if it goes past the default 60 second timeout before a response is received from the server, but these are in the minority. Some say ELB doesn't retry requests. The AWS documentation doesn't say what happens when an ELB times o...
3
5
2,262
2016-07-27T00:19:54.613
database_errors
serverfault.com
691,266
Is having the same PTR hostname valid for multiple ip addresses?
Currently I have the following setup with two hostnames and two ips: [CODE] I want to change to having a round-robin dns for a single hostname using the two ips. Are the following PTR records valid? Can a host have multiple IPs and with each having valid reverse dns resolution? [CODE] EDIT: Please note that this questi...
Yes, it's valid. But... Some programs do a "double-reverse lookup" or as Wikipedia calls it, Forward-confirmed reverse DNS . Quoting from the wikipedia entry, "RFC 1912 and RFC 1033 (Informational) recommend it as a best practice , but it is not a requirement of standard defining RFCs governing operation of the DNS." (...
3
2
2,294
2015-05-11T21:36:09.233
data_quality
serverfault.com
834,430
How to verify mysql single process with multiple threads model?
It is said that MySQL handles connections, allocating one thread per connection to the server,and MySQL is a single process with multiple threads. Now in my localhost . There are two connections to mysql. [CODE] Let's search 892's ps tree. [CODE] Are there 14903 and 14937 threads?Which process do they belong to? It mea...
You need to differentiate between [CODE] and [CODE] . The latter is the client program you use to manage the server.
0
0
621
2017-02-23T11:55:38.470
api_errors
serverfault.com
291,448
Database design: manage permissions on multiple applications resources
Overview A central web application to supports other web applications(A) for user and its role/permission management. Applications (A) call the central application via API to get the user roles/permissions. 1) Application(A) can have resources. 2) Resources can have permissions. 3) User can have access to resource/perm...
I think requirement #3: "Users can have access to resources/permissions" is a little vague. Until you're more specific in your requirements, it cannot be answered. Here is how you can look at your two scenarios and make a decision. In scenario #1 a user can only have access to a resource by having a permission that is ...
3
2
5,818
2015-07-31T14:22:47.403
api_errors
softwareengineering.stackexchange.com