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38,321
How can I motivate management to allow freelance work?
I'm a developer at a small company. Sometimes I'm offered extra cash for freelance work from previous employers or on odd jobs that I could do after hours without encroaching on my full time job in any way. Unfortunately my manager has explicitly forbidden me from working on any side projects. The reason he says is tha...
The reason he says is that if I have any free time at all in my life, even on weekends, they should be spent working for his company. Quit the company NOW!
14
64
1,020
2011-01-20T04:50:58.370
api_errors
softwareengineering.stackexchange.com
1,131,790
PuTTY Reverse Tunnel to MySQL
I have: A local [CODE] PC running MySQL Server 8.0.33 on port [CODE] . A remote [CODE] VPS running MySQL Server 8.0.33 on port [CODE] . I want to create a reverse tunnel using PuTTY on my Windows PC so that my Ubuntu VPS is able to connect to my local MySQL instance running on port 33060. For example, I'd like to conne...
What ended up solving the problem was changing the PuTTY settings to: Apparently, port [CODE] uses the X protocol , not the classic MySQL protocol. From my testing, it seems changing the port makes a difference with the Ubuntu MySQL client (even though the Windows MySQL server port is exactly the same and [CODE] shows ...
0
0
226
2023-05-24T03:17:14.930
api_errors
serverfault.com
439,399
AWS ELB Not working as desired
Trying to load balance my app with the use of an AWS Elastic Load Balancer. The app is a custom TCP-based sender/receiver. In any case, ELB seems to send 100% of the traffic to one machine, neglecting the other healthy attached instance. I see no options in changing the round/robin behavior... Suggestions? Thanks!
If the only traffic is from your testing, you possibly might always hit the same server, even if server stickiness/affinity is disabled. If the servers are in different availability zones, there are multiple ELBs setup (one in each AZ) and they're all returned in the DNS request for the ELB. The OS is going to chose on...
2
0
1,055
2012-10-17T15:51:50.523
database_errors
serverfault.com
235,263
Host www.xyz.in not found: 3(NXDOMAIN)
I have a domain purchased from name.com - I am using heroku for hosting a rails app for this domain. Today I tried to setup DNS for this domain. The top level domain works fine but when I try to setup CNAME for "www", I get the following error : [CODE] My CNAME settings in name.com looks like : [CODE] This is as per th...
I highly suggest using a A record for www ,as a Cname will cause 2 lookups at the server doubling the load. Cnames were designed fir when you don't control the other domain, An A record is much more suited for this
0
0
4,135
2011-02-14T12:46:51.157
infrastructure
serverfault.com
283,182
Zabbix MariaDB Copy item data to another item
My current DB: [CODE] There are some duplicated items in my Zabbix. I have the old item which has "history" and "trend" data, but it was disabled. The new item also has data and is enabled. I thought of copying old item history and trends to the new item but I'm not really sure how to do it safely. I created some test ...
After some digging, I managed to successfully copy history and trends from one item to another. The sort of syntax I used is this: History table: [CODE] Trends table: [CODE] The secret was with INSERT INTO and the SELECT clause that added the literal itemid. The actual was inserted into every new row. The result: [CODE...
1
1
389
2021-01-13T21:38:17.383
database_errors
dba.stackexchange.com
283,683
OO design in a data processing pipeline
I'm wondering how to design a fairly simple class whose properties are complex to compute. Also, the properties depend upon each other for computation. An example using graphs and graph processing (think nodes and edges, not charts or scatterplots) to motivate the problem: Class [CODE] is a collection of [CODE] instanc...
I think that the two problems you listed arise not from your design but rather out of the problem you are solving. Depending on how generic you want to make your design, you could have some meta-data that defines each major processing step, and then some methods that you call to "push" the pipeline into the next step. ...
5
2
1,166
2015-05-12T22:38:02.657
pipeline_ops
softwareengineering.stackexchange.com
95,096
Unable to use a temporary table more than once
I am using SQL Server 2008 to build a stored procedure. In it, I create a temporary table (#results) using recursion for getting all the ancestors given a specific record. My specific problem is, when I try to use this #results table twice, the second time it returns this message: Invalid object name '#results'. Here i...
Community wiki answer generated from comments to the question by various people. Despite the name, you are declaring [CODE] as a Common Table Expression (CTE), not a temporary table. CTEs only apply to the same statement they are defined in. You can solve your problem using a temporary table, using syntax like: [CODE] ...
1
2
2,974
2015-03-12T17:14:32.550
database_errors
dba.stackexchange.com
808,603
arp broadcast responds with several different MACs for same IP
I'm experiencing an issue that's causing a lot of problems on our LAN. I have a Windows Server with a single NIC, 192.168.0.100 I have certain services running on the server that I am having connection issue with, database being one, SQL. When accessing this issue I notice that if I send a broadcast arp request for the...
I've never done this on Netgear but according to the GS700TS Smart Switch Software Administration Manual in the web interface you need to go to Switching > Address table > Basic > Address table. Select "search by mac address". Enter one of the "offending" mac addresses (e.g. xx:xx:xx:xx:BB:A9) and click Go. This will t...
1
1
1,872
2016-10-12T13:26:48.210
infrastructure
serverfault.com
909,988
Not able to connect to ec2 instance after associating elastic ip to it and adding proper security group
I have installed wordpress on my ubuntu16.04 LTS instance of ec2. I was able to connect to it via public DNS. But then I added the Elastic IP to the instance and tried to connect to the instance via my browser but it took a lot of time and the browser ended up saying "This site can’t be reached". I have added security ...
From your question, it looks like you want to connect to your original instance public IP after associating an Elastic IP to it. That is not possible: as soon as you associate an Elastic IP to your EC2 instance, the old public IP address is released. See: https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/elastic-ip-a...
1
0
1,680
2018-04-30T10:08:46.443
database_errors
serverfault.com
329,272
Poor NFS performance when sequentially reading large files
I have an NFS3 server with multiple clients. Each client is sequentially reading a different large file, and performance is very poor. Here is what I am observing in [CODE] on the server for the disk where the files reside: Device: rrqm/s wrqm/s r/s w/s rMB/s wMB/s avgrq-sz avgqu-sz await svctm %util sdX 24.33 0.00 712...
Faster disks, more memory in the box. I think your conclusion is right - you're seek bound. How much memory does your NFS server have vs. your working set? Will your working set fit into cache? What is the backend storage? You say it does ~180-360MB/sec throughput but how does it perform for random I/O? I'd suggest usi...
5
1
3,067
2011-11-09T12:44:51.617
infrastructure
serverfault.com
503,501
cannot modify sshd_config as Root (centos)
After looking through several threads on securing SSH on our server and have run into a little trouble when modifying sshd_config. I went through making the relevant changes and when I exit the file to save it I get a permission denied error. I am still fairly new to the linux server environment and any help in working...
please run below command to reset attributes of file: chattr -ais sshd_config Now you will able to modify your file.
0
1
2,881
2013-04-29T11:15:12.640
infrastructure
serverfault.com
679,391
AWS StrongSwan IPSec VPN
I've been playing around with StrongSwan recently as a replacement to Amazons VPN which cost money. I'm having trouble completely configuring a IPSec tunnel between a remote server and a Ubuntu EC2 machine running StrongSwan. My goal is to have our remote server be able to VPN into our VPC and have bi-directional acces...
I turns out, I had made a mistake and there was a post-routing issue on the client gateway, hence why traffic was only being permitted in one direction. StrongSwan and AWS were configured correctly.
5
2
4,710
2015-03-30T19:00:49.683
infrastructure
serverfault.com
431,944
install boot with raid 1 in 3 TB disks
I'm trying to install /boot in a RAID 1 using 3 TB disks. As the RAID partition do not let you manage partitions than more than 2 TB, CentOS automatically configures the partitions using GPT. My current machine (HP Proliant ML110 G4) does not support EFI/GPT so it uses MBR to boot the system. If I configured the /boot ...
Did you make sure to install the boot loader on all of the hard drives? With a raid1 set as your boot partition you have to install grub on each hard drive in turn - or at least you used to with smaller disks using MBR partitioning I'm just now doing this on a server I have (upgrading storage space) so I'm curious if y...
1
2
492
2012-09-25T21:50:49.270
infrastructure
serverfault.com
377,932
Total RAM % from perfmon Windows Server 2008 R2
I am trying to find a good way to get available RAM percentage from perfmon. I can get Available Mbytes but I can't find any way to get the total installed memory on the server or what is in use via perfmon. I can obviously alert on GB but each of my servers have different total RAM so not a great alert. The way I unde...
Sadly, there is no default Performance Monitor counter that does this . You will need to consider using WMI to tally the total RAM in a server, then totaling the amount of used RAM versus free RAM, storing that data as it is collected, and then presenting it in a pretty way. However, that kind of thing has already been...
10
8
9,473
2012-04-09T20:53:31.917
infrastructure
serverfault.com
5,473
Oracle get sql redo from log_history
I run into a problem with a customer which had no proper backup. His last backup (meaning exp-dump) is from 1st Aug 2011. However he lost due to batch DELETE statements all data. My plan was now to get the redo-sql from the logs, import the dump and replay all sql from 1st Aug up to 2nd Sept (just before the batch DELE...
First of all export is not backup . You will not recover a physical copy of a database from exp-dump, only an unconsistent copy of its data (you can make them consistent but the option is rarely used). I'm really not sure you can apply the contents of logMiner on such a copy. Your best bet would be to apply undo statem...
2
4
1,575
2011-09-07T09:54:29.540
database_errors
dba.stackexchange.com
353,820
Synching 2 remote folders
We have 2 Drupal servers that [CODE] to their own copy of the same folder (the [CODE] folder for those of you who know a bit about [CODE] ). Those 2 folders should be in sync. I've been looking into some options and here is what I found out: OPTION 1: Rsync both ways : not an option You would need to run [CODE] both wa...
Is it necessary for you to use 2 copies of Drupal? Drupal makes a lot of queries per page request, having multiple Drupal front-ends sharing a remote database backend can be a pretty big performance penalty. Have you consider using multiple caching frontends and a single drupal + database backend? Pressflow is an enhan...
1
2
360
2012-01-26T11:38:47.363
infrastructure
serverfault.com
147,178
how to test if XML = '' in sql server?
I am working with sql server 2005 and I had a situation where many values can be passed in a parameter. Based on this: Passing multiple values for one SQL parameter this procedure uses XML as a parameter. here is the code of the stored procedure: [CODE] more info about this procedure here this is an example of how it c...
You may check for [CODE] and nodes absence ( [CODE] method of [CODE] type): [CODE] Your XPath can be more specific, if necessary: [CODE]
11
10
24,484
2016-08-18T09:58:18.900
database_errors
dba.stackexchange.com
607,061
Enabling Cloudflare via cPanel shows error: "Your DNS is hosted by CloudFlare..."
I'm trying to configure the DNS for my CloudFlare in my cPanel my host provided me and this keeps happening! But, the thing is that my domain is already pointed to my CloudFlare and I waited 24 hours, got an email saying it was updated fully and stuff. Now I tried hooking it up with my hosting by using the cPanel, this...
You should just click the grey cloud to toggle the cloudflare. Remember you can just click the clouds to turn on or off the cloudflare for your domain. Delete your domain from cloudflare and try again via your cpanel.
-1
0
650
2014-06-22T05:22:42.207
infrastructure
serverfault.com
165,952
Connecting to MSSQL on EC2 from local
Has anyone ever managed to connect to Microsoft SQL Server (preferably 2008) hosted on Amazon EC2 from Management Studio on your development machine? I have set up the security group to allow port 1433, opened port 1433 outbound from Windows Firewall to no avail. Error from Management Studio is '26 - Error Locating Ser...
Check list to enable connection: First of all, determine the port number that you want to access to (default is 1433 but you may want to change this. For this example, I picked 5555.) Allow connection to this port on EC2 Security Group. Add TCP/5555-5555/all. Allow inbound connection to this port on Windows Firewall. A...
2
3
13,046
2010-07-31T23:18:02.140
database_errors
serverfault.com
21,958
One-class classification in Keras using Autoencoders?
I am trying to develop a model based on one-class classification approach. For example, the model should to identify if a given picture contains a cat or not. Keep in mind that my training dataset only contains pictures of cats and nothing else. Sort of like a anomaly detection problem I have seen some suggestions on u...
If you have images of cats only, you could create boundary boxes (BB) of your images. Some BB will have cats an others won't. You will label those BB with cats inside as 1 as the others as 0. This way you can set up a dataset with a binary class. It will be much easier if you already have boundary boxes for the cats in...
3
1
4,966
2017-08-04T13:33:15.220
data_quality
datascience.stackexchange.com
758,754
SFTP with chroot depending on public key of connecting user
I want to build a server (running Debian or FreeBSD) that receives backups from different clients via sshfs. Each client should be able to read and write its own backup data, but not the data of any of the other clients. I had the following idea: each client connects via public key auth to backup@backupserver.local. Th...
Alternatively, are there other SFTP servers that can do what I want? yes, you can use proftpd Prepare user environment. With ProFTPD there is no need to give to user a valid shell. [CODE] In order to use OpenSSH public keys in a SFTPAuthorizedUserKeys, you must convert them to the RFC4716 format. You can do this with s...
10
5
3,731
2016-02-21T14:41:52.893
database_errors
serverfault.com
418,912
Why were default methods introduced to Java?
Was introducing default methods to java inevitable? As far as I know multiple class inheritance was not introduced to avoid difficulties with the method signature clash in base classes. So we avoided it with classes and on the other hand we introduce this problem with default methods as we have to override default meth...
The reason that default methods were introduced was that without them, it's impossible to add new methods to an interface and maintain backwards compatibility. As explained here : Default methods enable you to add new functionality to the interfaces of your libraries and ensure binary compatibility with code written fo...
5
13
1,233
2020-11-12T19:06:34.720
api_errors
softwareengineering.stackexchange.com
42,773
How do I build a permutation invariance neural network in keras?
My question is about the structure of the network required to solve my problem with fewer data. I have a sensor device that simply reports the color of the thing it's seeing in front of it. One sensor reports me 4 numbers: Red, Green, Blue, and Alpha. The intensity of the color changes depends on the distance and the t...
I have found the solution. And I've written the code for it, for anyone interested please check: https://github.com/offchan42/superkeras/blob/master/permutational_layer.py It's an implementation from a paper. It's about pairing all 2 inputs and use the model that takes in 2 inputs. The model are shared and the output o...
3
1
981
2018-12-17T18:02:47.983
data_quality
datascience.stackexchange.com
877,243
My hosted server is being used to DDoS using LDAP, how do I stop it?
I recently was told to manage our exchange server because the person responsible left without decent warning. I have next to no experience in this regard, however everything was running smoothly for a few months. Our hosting provider just sent me this message: [CODE] How do I go about to prevent this protocol abuse wit...
I would use the following logic for your specific case; Identify if it is a managed, or unmanaged server. Since they are asking you to take care of it, it sounds like it is an unmanaged server. If you can log into Windows Server and change/install stuff then it is unmanaged. Use a firewalling (Windows Firewall) product...
1
1
2,841
2017-10-06T13:01:47.023
data_quality
serverfault.com
46,061
Selenium test coverage visualization
We have a huge legacy application where unit/integration tests are impractical and most automation is done in Selenium with Java programming language in a separate automation project. There are about 1000 @Tests written, the tests use Page Object Factory implementation and they check: business rules (requirements) crit...
I feel your pain. I live your pain: I am in the same situation, except I'm the only tester in the group and it's taken me years to get any stable, working test automation running. I'm not aware of any tooling that can be used to measure coverage in this kind of situation. When you're dealing with large legacy software ...
1
2
678
2020-10-28T09:23:01.163
bi_errors
sqa.stackexchange.com
207,847
Check by program if eth link is up or down on linux o.s. ...and kernel 2.4
I need to check the change in the status of eth connection ( link up and link down ) by program ( using c or perl ). Now I using the keepalive way, but i sometime loose the notification. Inside the messages files I see the kernel notification of 'eth0 link down' and this note are always correct so I looking for a way, ...
If you want to check the link status (carrier), you can check the file: [CODE] This will show 1 (link is up) or 0 (link is down).
0
2
1,710
2010-12-01T13:09:28.950
infrastructure
serverfault.com
169,429
mysql - query to fill in missing datetime values
I have a Table similar to: [CODE] It contains a list of events with the time it happenned, and the value. I am now looking to generate a report from this similar to: [CODE] In other words, get the [CODE] value for all entries per minute for the past hour. However, in some cases I don't have an entry for some minutes, b...
Filling in 'missing' rows is done via an extra table with all possible values, plus a [CODE] : Create have a table [CODE] with all possible minutes (in some finite range). (If using MariaDB, use a "Sequence" table.) Then [CODE] Note: Both tables should exclude or include the [CODE] for seconds. Otherwise (I think) ther...
0
0
4,176
2017-04-07T10:26:47.403
database_errors
dba.stackexchange.com
302,512
A beginner question on Primary Key VS Unique Key, Not Null
I am new to Databases and while i was studying about constraints in SQL. I came across Primary Key, Unique Key, Not Null Constraints. As per my understanding a primary key is used to uniquely identify a column in a table and cannot have null values. A unique key can have one Null Values and cannot contain duplicate val...
There's a bit if history involved here. When you design your tables, you have a number of "candidate keys". Column (a) can identify a row So can columns (f,g) So can column (i) The late Edgar Codd decided that one of those should be considered "better", "more important", "stronger" or whatever than the others. This is ...
1
3
1,398
2021-11-12T06:04:13.787
data_quality
dba.stackexchange.com
255,100
Count Sort Algorithm efficiency
As I read a book about "Algorithm Analysis", I came across [CODE] Algorithm. However, I have read elsewhere that "Quick Sort/ Merge Sort" are the best and the most efficient sorting algorithms. I found this confusing because the complexity of [CODE] is [CODE] , which is better than Mergesort and Quicksort which are O(n...
Counting sorts fail when there are large key values (the k in the O(n)). This means that if you have a large variety of key values, counting sort will be slow. Radix sort can help solve that problem but it does nothing for other issue. Both counting and radix sort are only valid for integer keys. While not a terribly s...
0
6
2,638
2014-09-02T01:51:15.057
api_errors
softwareengineering.stackexchange.com
910,171
how to forward ports through multiple hops with iptables
I've been wrestling with this for some time now and despite my efforts and can't make it work. I want to forward ports from the public IP to a host (host1) on the corporate network. Thing is, there are multiple "hops" in between. The host is behind a firewall which is behind a linux router set as a vpn client. All traf...
OK so it finally works. Turns out it was some kind of bug in the firewall. After I installed an update which required a reboot I gave it another try and it worked no problem. Maybe an old iptables rule in the firewall was the blocker...
1
0
968
2018-05-01T14:48:55.210
infrastructure
serverfault.com
1,095,852
Is it possible to track which employees handled M.Exchange emails of a big company?
Background: Company uses Microsoft Exchange, has several email accounts that need checking(contactus, faxes, admin, comm, etc). Several employees (over 10) check these accounts throughout the day. Once an email has been dealt with, the employee has been directed to archive the email in a respective folder (DONE, Called...
You will want to enable Mailbox Audit Logging on the mailbox(s) in question. When you enable audit logging for a mailbox, you can specify which user actions (for example, accessing, moving, or deleting a message) will be logged for a logon type (administrator, delegate user, or owner). Audit log entries also include im...
0
1
72
2022-03-10T14:37:27.687
hadoop_errors
serverfault.com
329,968
Column isn't in GROUP BY error on join query
I'm trying to get best selling products. Tables [CODE] [CODE] Following is the query, [CODE] The error is [CODE] Can I gen an explanation of why I'm getting the error? This query also works on DB clients (such as tableplus) but not in app (Laravel). How do this can be done?
You have 3 columns in the select clause which are not part of the aggregate functions [CODE] , [CODE] , [CODE] nor part of the group by clause. If you select a non-grouped column or a value computed from a non-grouped column, it is undefined which row the returned value is taken from. This is not permitted if the ONLY_...
2
2
285
2023-08-04T13:05:01.420
warehouse_errors
dba.stackexchange.com
721,211
remote desktop gateway licensing mode for administrator only usage
I have setup a remote desktop gateway but only intend to use it for administrative access to servers. Correct me if I am wrong but as long as I am only using the RD Gateway for administrative purposes and limit it to two connections per server at a time I don't need licenses. If that is true then, how do I get the gate...
Your interpretation is more or less correct. If you don't add the licenses, it will terminate other sessions when sessions past the first two are created. There's also a console session which has special rules.
0
0
2,525
2015-09-09T14:33:21.833
infrastructure
serverfault.com
726,338
Windows Server 2012 Terminal Server Degrading Performance on User Session
We have a terminal server environment with about 40 users which is experiencing a curious performance issue: when a given user logs in initially, everything functions properly, once a particular user starts to eat up more resources (upwards of 2GB/memory and 2%-5% of overall CPU usage), their applications seem to slow ...
I would look at WSRM https://technet.microsoft.com/en-us/library/hh997019.aspx The default resource allocation is to divide up resources per number of connected users so, if you have 40 users each user will only be able to access one 40th of your memory and CPU. Weighted_Remote_Sessions might be a more appropriate conf...
0
0
1,389
2015-10-02T16:45:51.563
database_errors
serverfault.com
77,780
Raising an Alert with THROW
It seems to me that SQL THROW is missing a crucial feature that [CODE] has, and that is the abilty to use [CODE] so that an Alert can be fired when the error number is logged in the Application log. Is there a simple way to do this that is escaping me or do I still have to rely on the more cumbersome [CODE] and [CODE] ...
No, [CODE] is missing some [CODE] functionality, including [CODE] . I blogged about this back when SQL Server 2012 was still in beta, and no changes have been made since: SQL Server v.Next (Denali) : Exploring THROW However, you don't need to use [CODE] to send [CODE] messages to the log, unless you need a custom messa...
2
5
853
2014-09-26T16:45:40.497
warehouse_errors
dba.stackexchange.com
733,429
Define marathon services listening interface
I have a mesos install with 3 VPS. I use a virtual private network for internal networking. Everytime marathon starts and bind a service to a new port, it binds it to 0.0.0.0. No matter if I had a http(s) load balancy security in front, every user can access any service by doing a simple [CODE] Can't find anything in t...
Use environment variable [CODE] set binding address. You can set it in [CODE] or any file that is sourced before starting Marathon service. [CODE]
1
1
61
2015-11-02T23:13:12.340
infrastructure
serverfault.com
593,430
chef remote_file is throwing Encoding::UndefinedConversionError
I have the following in a chef recipe: [CODE] On Ubuntu 14.04 with ruby1.9.1 this is throwing "Encoding::UndefinedConversionError: "\xA2" from ASCII-8BIT to UTF-8" when I run chef-solo on boot. If I run chef-solo manually after start up, the cookbook completes successfully. This seems related to https://github.com/yevg...
Seems to be this bug: https://tickets.opscode.com/browse/CHEF-4746 I'm going to downgrade to chef-solo 11.4
0
0
850
2014-05-06T15:28:28.783
pipeline_ops
serverfault.com
767,709
Why can't I uninstall mysql-5.5 & install mysql-5.6 on Amazon Linux machine?
I'm on a 64-bit Amazon Linux machine. I had previously installed mysql-server 5.5. (using [CODE] ) However, I soon found out that my application requires MySql-serve 5.6. So I uninstalled mysql-server 5.5. (using [CODE] ) and now I'm following these instruction to install mysql-server 5.6. But I'm running into a proble...
@Doug's answer helped me solve it: You probably need to remove mysql-client as well. I would 'sudo yum list installed | grep mysql' and see if there are any other mysql packages installed.
1
5
3,274
2016-04-02T08:52:35.473
database_errors
serverfault.com
318,113
How do I alias a name in nginx w/o aliasing the domain name?
I have this line in my config file [CODE] My code checks if the url is [CODE] and serves the mobile version. However when I do this going to [CODE] will show my code [CODE] which is wrong. If I copy/paste the entire block and change site.com to m.site.com it works fine. But I'd rather not have duplicate config (or code...
It is an ineffective way even if you check [CODE] in config. So, the best way is put all common bits in a file and include it in separate [CODE] block: [CODE]
2
2
10,792
2011-10-03T21:18:47.523
data_quality
serverfault.com
58,570
How do I use this depth first search code to obtain a topological sort?
Problem : I need to implement a topological search using the following depth first search code. Note : The original code comes from here, and this is a problem given in at the end of the chapter. I'll be honest. On a coding level, I feel pretty lost. I've added line comments to help show what I think each line is doing...
It appears to me that you are doing too much with the code. For DFS, visit every node following adjacent nodes. As you do that, track the topological ordering. Here is a straightforward implementation of recursive topological sorting a DAG in Python: [CODE] [CODE]
0
1
589
2019-09-02T22:04:17.943
data_quality
datascience.stackexchange.com
175,119
UNION ALL date on the same row
I am unioning multiple tables together in Postgres, where the timestamp is slightly different, but the same if I round to the hour. Is it possible to make each union show on the same row, if the date is the same? Currently I'm getting duplicate rows of each date. [CODE] It returns:
You can use FULL JOIN like this: [CODE] Or just use CASE : [CODE]
0
1
2,240
2017-06-01T08:11:00.793
data_quality
dba.stackexchange.com
643,779
High Load Website. how to load balancing?
i have the following problem: i have two servers (intel xeon 3,4 GHZ with 32GB RAM and RAID 10 (4x1TB Enterprise Harddiscs). all servers are installed with vmware esxi 5.5 (free). webserver, dbserver all are virutal machines. the first is a webserver with the newest debian x64 and apache 2. load: 50% the second server ...
Bunch of things going on here. In the general category of performance tuning, there are multiple levels/steps in the process. You seem to be skipping to the last step first. Generally this is how I approach it in my work: User experience vs. Hardware statistics. First rule: if a site works fine for an end user, backend...
0
2
279
2014-11-12T12:56:40.533
database_errors
serverfault.com
120,062
Is it valid changing the classification treshold of neural networks for improving the classification performance?
I'm dealing with text classification using BERT pre-trained model with a multiclass imbalanced dataset. When we use a 0.5 default classification threshold we obtain a f1 measure of around 0.7. But we have noticed that when we decrease the classification threshold we obtain a better performance. If we use different bina...
Yes it is a very common thing to do, for controlling tradeoff of objectives. One often encountered example is to precision-recall tradeoff where we move the threshold to strike a balance between desired precision and recall level. As a note, this practice is for classification in general, regardless of neural network o...
1
3
60
2023-03-09T01:33:19.453
data_quality
datascience.stackexchange.com
191,406
PostgreSQL: Running SELECT DISTINCT ON ~700m rows - how to optimize?
I have a table that, if we look at just the relevant parts, has two columns: [CODE] and [CODE] . [CODE] is an integer, and [CODE] is a text blob. At this point, the table has no constraints or indexes except for an index on [CODE] . My goal is to deduplicate (by [CODE] ) this data and dump it all to plaintext files (on...
Thanks to ypercube's tip in the comments above, I was able to keep the time per chunk of the query constant, and so good enough for my one-off purposes. I'm now running: [CODE] Takes about 1 minute per query. My whole process will take about 48 hours, but that's good enough. Could definitely optimize further with multi...
2
2
2,210
2017-11-21T14:34:05.947
database_errors
dba.stackexchange.com
137,638
'OraOLEDB.Oracle' provider is not registered on the local machine - Oracle Database Client 12C
I have some problem with connect to the Oracle Database by Oracle Client. I installed on laptop oracle client - version 32 bit. I can connect to the database from laptop when i use 64 bit applications, but when i will use 32 bit application i get following error: [CODE] i have seen this question ' https://stackoverflow...
From comment by Wernfried Domscheit : Have a look at this instruction to install both 32 bit and 64 bit on one machine: stackoverflow.com/questions/24104210/… . Note Oracle OLEDB provider is not included in Oracle Instant client, you have to install it separately or enable the corresponding option in Oracle Universal I...
2
1
15,234
2016-05-05T12:24:00.273
database_errors
dba.stackexchange.com
436,981
Why does this script stop/fail to continue in Ubuntu 10.04
I have the following script, which works fine until the end of the script where the line to install JRuby [CODE] works, but then the script stops. I added [CODE] at the end of the script to try to get it to output the exit code from the previous line but the error code doesn't get printed. [CODE] If I run the JRuby ins...
Whether the JRuby install command succeeds or fails wouldn't matter to the script, since it doesn't check the return code in order to apply any logic. My guess is that the problem is with the previous command. First, do you get the sudo prompt for a password? Second, how does "install.sh" end? It may do an exit; since ...
0
1
466
2012-10-10T19:10:20.307
infrastructure
serverfault.com
237,693
Creating Active Directory on an EC2 box
So I have Active Directory set up on a Windows Server 2008 Amazon EC2 server. Its set up correctly I think, I never got any errors with it. Just to test that I got it all set up correctly, I have a Windows 7 Professional virtual machine set up on my network to join to AD. I set the VM to use the Active Directory box as...
Did you enable all the necessary ports in the security group? See this post...
0
1
1,415
2011-02-19T19:58:59.037
infrastructure
serverfault.com
276,776
How to share a unique value between tables efficiently [postgres]
We are modeling the concept of a global "reference code" for some of the records in different tables in our system (e.g., [CODE] ). A "reference code" needs to be unique, easy to say over the phone, and can refer to a handful of different entities in our platform (e.g., people or places). The criteria is: one pool of c...
Use [CODE] values generated by a single sequence. Numbers are quite easy to say over the telephone. Forget about the requirement of enforcing database-wide uniqueness. Unless someone manually messes with the data, the sequence will guarantee the requirement. The performance cost of enforcing such a requirement with dat...
1
2
607
2020-10-08T20:08:50.303
data_quality
dba.stackexchange.com
274,631
How is it technically possible for PostgreSQL to keep small tables "in RAM"?
I used to ask about performance and people would tell me that PostgreSQL keeps small-enough tables entirely in RAM automatically, as to not stress the HDD and thus enable super-fast reading/writing of "small tables", that is, with very few rows which more than easily fit in the available RAM (or what's assigned to PG)....
This is possible due to Write-Ahead Logging (WAL) : Briefly, WAL's central concept is that changes to data files (where tables and indexes reside) must be written only after those changes have been logged, that is, after log records describing the changes have been flushed to permanent storage. If we follow this proced...
2
6
585
2020-08-30T00:53:04.597
database_errors
dba.stackexchange.com
817,332
Two ISPs on Separate Routers One Server 2012R2 With Two NICs
I have two separate networks I would like to join to a single Server 2012R2. One network has a router attached to a T1 line which has a fixed public IP address. This keeps an open FTP line to upload weather station data and webcam photos to several websites. The fixed IP is needed to keep the FTP open at all times. Pre...
2 different IPV4 Address spaces will work, if your currently using a /24 mask(255.255.255.0) I'd stay with that and set up a 10.0.2.0 and 10.0.3.0 network. however if you use that approach you'll need to set up routes on the server 2012 machine to tell it how to reach the rpi's on the secondary network. while this woul...
2
0
322
2016-11-27T16:46:11.110
database_errors
serverfault.com
668,000
Unmounted directories still behave like mounted - NFS Server Ubuntu 14.04
I am working on two virtual machines, running Ubuntu 14.04. So, one VM is the server and the other the client. Here's what I've done till now: Server VM: [CODE] I added: [CODE] Client VM: [CODE] and everything works fine. Then I need to unmount them so I run the command on the client VM: [CODE] Just to be sure I run th...
I noticed that in order to mount/umount work properly, I need to run a simple cd command. Any ideas about that? If you are currently in a directory that is within a mounted filesystem and you try to unmount it, you normally get an error message that the fielsystem is busy the effect of this is it can't be unmounted e.g...
1
2
810
2015-02-16T10:51:30.057
infrastructure
serverfault.com
328,939
nginx - redirection doesn't work as expected
I have a domain listening on both http and https. I want to redirect all the traffic to https except for two specific locations. It works, but only for mydomain.com, not for www.mydomain.com. Here the config: [CODE] I defined the blog upstream. As said, it works properly for mydomain.com, but not for www.mydomain.com. ...
Because on line 43 you say to redirect to https:// (but you're not listening on 443). Change that to http I would also change it to two server blocks, the first is [CODE]
2
0
931
2011-11-08T16:14:54.827
infrastructure
serverfault.com
1,153,206
How to send email from smtp server1 to smtp server2 (Postfix) via client?
How to make server1 with postfix can send email to server2 with postfix by redirecting DNS query to it (type forward). These servers are on the same local network. Server1 is to receive a non-authoritative response from server2 about the serverx.eu domain. Server1 has the a@serverd.com box, and server2 has b@serverx.eu...
If you have control of both servers and the client uses one of them as a mail submission server then use [CODE] transport maps to route the mail, no need to manipulate DNS.
0
2
44
2024-02-09T01:38:13.720
infrastructure
serverfault.com
731,130
Bios Error on reboot Insuficient PCI Ressources xeon phi , supermicro-server
I currently have a problem with an supermicro-server with an intel xeon phi installed. Its an old server, but when I am logging in and checking for the xeon phi it is still recognized. When I am trying to reboot the system there is a "Bios Popup Message" which is telling me "ERROR: Insuficient PCI Resources Detected!" ...
I'm unsure if you fixed this or not, but I just had the same issue. I was able to resolve it by doing what you said in your comment, I additionally changed: Changed MMIO High Size to 1024 GB MMIOHbase was set to 56 TB Set Above 4G Decoding to enabled Enabled PCI PERR/SERR Support SR-IOV Support to enabled I'm running o...
0
1
2,245
2015-10-23T09:00:06.877
infrastructure
serverfault.com
1,031,906
Why my domain doesn't map to the server address?
I have installed DNS server and network manager on my remote server as by following this instruction: https://www.linuxtechi.com/setup-bind-server-centos-8-rhel-8/ as below: var/named/fwd.sssss.com.db: [CODE] var/named/sssss.com.rev: [CODE] etc/named.conf: [CODE] /etc/sysconfig/network-scripts/ifcfg-enp0s3: [CODE] etc/...
The question is not easy to understand, as noted in the question comments, but it seems the issue is with DNS resolution on the client . This is most likely due to one of three reasons. Nameserver entries at your DNS registrar are wrong. If your client is using a public DNS resolver (e.g. Google, Cloudflare) they will ...
0
1
117
2020-08-28T17:38:27.513
infrastructure
serverfault.com
260,524
Confusing MySQL error/warning/info message
I am having trouble administering my MySQL. I tried to stop it like this: [CODE] and I got this message: [CODE] So I tried doing this: [CODE] My OS is Ubuntu. Any ideas why I seem to be running into this dead end? :)
You need superuser rights to run [CODE] : [CODE] or (as root): [CODE] Using the [CODE] and [CODE] utilities is now the defacto standard for service initscript handling on most Linux distributions. EDIT: If none of the above works, you can try [CODE] directly: [CODE]
0
2
1,333
2011-04-16T00:05:18.883
database_errors
serverfault.com
438,360
How does rsync --daemon know which way it is being run?
I am wanting to run rsync over an SSL/TLS encrypted connection. It does not do this directly so I am exploring options. The stunnel program looks promising, although more complicated than designed due to the need to hop connections with the -r option. However, I do find there is a -l option to run a program. I am assum...
From the section on [CODE] in the [CODE] man page: If standard input is a socket then rsync will assume that it is being run via inetd, otherwise it will detach from the current terminal and become a background daemon. You can see the command line arguments that apply to daemon mode by running: [CODE]
1
1
1,960
2012-10-15T05:29:44.163
infrastructure
serverfault.com
578,994
NGINX reverse proxy load balance client multi request
After spending the better part of yesterday trying to figure out why my load balancing and reverse proxy wasnt working in NGINX, it turns out it was and I was running into a different error all together. Im serving a CPU intensive REST API (Built in Flask) running behind multiple Tornado servers that were spawned by su...
I sorted this. Turns out that the error I was seeing was a result of using the same browser. NGINX doesn't considers multiple tabs in the same browser to be the same connection, so processes serially. If I send a request from two different browsers on the same machine it works fine. Chalk it up to error in testing meth...
0
0
2,342
2014-02-28T14:18:22.703
api_errors
serverfault.com
250,044
Connecting database from another network
We have a database in our server at work, and we can connect the database if we are connected to same network with server. I want to connect from my home. How can I do this? I have tried couple of connection strings. But none of them worked. Thank you all Best Regards
I suspect that the server is behind a firewall and you are being blocked. So unless your SQL Server is public, which I really hope that it is not - then you will need to speak to your Network Administrators and request external access via VPN or some other method.
-1
2
107
2019-10-01T21:42:25.660
warehouse_errors
dba.stackexchange.com
742,326
AWS vmimport - stuck on booting phase
Currently importing an OVA from an S3 bucket. Windows 2008 R2 Standard Process stops at the booting phase "StatusMessage": "FirstBootFailure: This import request failed because the instance failed to boot and establish network connectivity.", This is a single volume machine that boots up fine if the OVA is reimported b...
Have you checked all the Windows image import pre-requisites @ http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/VMImportPrerequisites.html ? Most notably: available disk space, NIC configuration (single NIC, IPV4, DHCP), Windows license (could you be hitting the Windows sysprep limit or similar issues), possible WMwa...
2
0
5,876
2015-12-11T03:18:17.763
infrastructure
serverfault.com
108,989
How do I get Brent Ozar's sp_BlitzIndex to run on Azure?
I downloaded the SQL Server First Aid Kit from Brent Ozar's website. When I tried to run the sp_BlitzIndex script against my master database via Microsoft Sql Server Management Studio while logged in as the Azure database server level admin and I got the following error: Msg 262, Level 14, State 18, Procedure sp_BlitzI...
Kendra here (the author of [CODE] ) First, thanks for being interested in the procedure and trying it out. Azure doesn't expose all the dynamic management views that we get in the boxed product. I do actually reference [CODE] , but there's other info I need to get from [CODE] for other users. (Is it using compression? ...
14
27
2,424
2015-08-04T17:31:31.800
api_errors
dba.stackexchange.com
422,010
Add module to custom compiled PHP
In CentOS I have a compiled version of PHP but it is missing IMAP module. Is it possible to add that module without re-compiling php?
Yes, you can just download the source of your current version, untar it, go the the ext/imap directory of the untared source then run: [CODE] You might need to run ./configure with some options specifiying the imap libraries used like: [CODE] After you compiled the module you should located it under ext/imap/modules, i...
1
1
1,565
2012-08-28T14:03:19.603
infrastructure
serverfault.com
120,283
Updating Windows DNS records from a remote windows DNS server
Does anyone know if it is possible for a windows 2003 DNS server to update the records for a domain so that it contains all the records of a domain of of a remotely based DNS server? Im almost certain that doesn't quite explain the problem so I shall illustrate with an example: We have two offices, both are based about...
Setup the call centre server as a secondary server for the IT zone.
1
1
271
2010-03-08T11:36:58.393
infrastructure
serverfault.com
445,609
Add Machine Key to machine.config in Load Balancing environment to multiple versions of .net framework
I have two web servers behind a F5 load balancer. Each web server has identical applications to the other. There was no issue until the config of the load balancer changed from source address persistence to least connections. Now in some applications I receieve this error Server Error in '/' Application. Validation of ...
If you only need it for your web site, you can add it to your web site's web.config. If there are multiple sites/applications that need to use the same machineKey for encrypting/decrypting, that is when you would use a machine-scoped configuration file. And yes, they should be the same across all servers in the farm, a...
5
8
27,171
2012-11-05T14:43:02.220
data_quality
serverfault.com
425,526
iptables redirect single website traffic to port 8080
My goal is to be able to make a connection to one, and only one, website through a proxy. Everything else should be dropped. I have been able to do this successfully without a proxy with this code: [CODE] How could I do the same thing except redirect the traffic to port 8080 somewhere? I've been trying to redirect in t...
I think the webserver configuration is better place to do this. Please check the virtual hosts configuration of the Apache server: Apache vhosts configuration: http://httpd.apache.org/docs/2.2/vhosts/examples.html Other servers have similar configuration. You can specify what websites (by URL) you want them to handle.
1
1
3,075
2012-07-09T15:23:39.497
infrastructure
serverfault.com
20,440
Protractor - element.all().count() is waiting long where there is no such an elements
I've got problem with some of my protractor tests. In short word, i need to check some numer of elements on my page with number from previous filter. When filter is clicked there should be displayed only A alements, B elements number should be 0. I realized that protactor is waiting for long time when [CODE] On this pa...
I only have experience with Selenium WebDriver, but most like Protractor has an implicit wait going on, which means it tries keep finding elements for a certain amount of time. You'll probably need to turn this off (to 0), in order for the method to immediately return a value (similar issue for Selenium's [CODE] method...
3
1
4,192
2016-07-07T14:55:28.357
data_quality
sqa.stackexchange.com
770,567
cant access network share windows server 2008 Domain
I am currently having an issue with one Windows 7 PRO pc(fully up to date windows and drivers) accessing one windows server 2008 share. This particular server 2008 share is accessed by about 20 users that have no issues accessing this share. I can see the file if I browse to the network share via [CODE] . When I browse...
Sharing folders in Windows can have the following issues: Local sharing, they must be on the same Workgroup. Firewall should allow sharing. With Windows 7, you should turn on Network Discovery and File and Printer Sharing. The one in the advanced setting of Network and Sharing. I'm did clearly get your setup specially ...
0
0
393
2016-04-15T11:14:33.257
infrastructure
serverfault.com
98,471
Managing DLL files, deployment, and ease of use for the end user
I've been thinking recently about being an end-user who wishes to download one of my own projects and use it on a perfectly average machine. Having an equal background in Unix as well as Windows, I know that package management on Unix makes it FAR easier for the programmer to make it easy for the end-user. If a package...
It's actually not a different story on Windows. You'd typically create an installer for your application. The user runs the installer, the application gets installed. That's it. There's two main approaches to use on Windows. You can use Windows Installer , which is the installer service that runs on Windows and install...
5
6
2,368
2011-08-04T05:01:11.943
pipeline_ops
softwareengineering.stackexchange.com
96,384
How to group list of start times by a category?
I have a list people and when they started occupied various rooms in the building. Like so: [CODE] I'd like to get that data grouped by person/floor with the next beginning timestamp becoming the end timestamp of the previous row. Like this: [CODE] I've tried to come up with various uses of window functions to solve th...
Using the newly added [CODE] and [CODE] functions makes it look easy: [CODE] Test in SQLfiddle
2
3
37
2015-03-26T20:20:28.907
warehouse_errors
dba.stackexchange.com
795,744
Using ansible cli to restart servers return an error (while still restarting the servers)
I can successfully connect to my server with ssh. Nevertheless, when I try to execute a command through Ansible cli, it fails: [CODE]
Everything in your output looks correct. Ansible establishes an SSH connection, runs its script (containing your command) and waits for its exit code. However you order it to issue an [CODE] command which reboots the server. The SSH connection is thus broken before the exit code is returned to the Ansible and Ansible r...
2
3
297
2016-08-09T12:17:25.493
pipeline_ops
serverfault.com
215,129
Will JVisualVM degrade application performance?
I have doubts in JVisual VM profiler tool related to performance. I have requirement to implement a JVM Monitoring tool for my enterpise java application. I have gone through some profiling tools in market but all them are having some kind of agent file which we need include in server startup. I have a fear that these ...
JVisualVM can cause performance problem issues for your application. It all depends on what you're doing with it. For example, if you're monitoring some GC via the JVM's MXBeans it has a fairly low impact (well actually, not that low if you're constantly monitoring). Another example - if you're profiling and recording ...
1
1
1,413
2013-10-21T16:59:55.100
pipeline_ops
softwareengineering.stackexchange.com
788,204
Cannot reinstall OpenManage 7.4 packages, claims dependencies are uninstallable
How the issue began Recently, whilst upgrading, OpenManage attempted to upgrade to version 8.3.0 and failed due to unmet dependencies with the message [CODE] . This is not the wanted behavior, as I want to stay on version 7.4 for support for older hardware. Attempted solution First, I uninstalled OpenManage using the c...
It seems that core libraries are not installable (like libsmbios2). You should have the deb source for the ubuntu dstrib itself somewhere in your sources.list of sources.list.d [CODE]
0
1
2,148
2016-07-06T10:45:09.980
database_errors
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
warehouse_errors
dba.stackexchange.com
907,722
Performance of iptables
I would like to ask you what is performance of iptables. Let's say that I whitelist and blacklist some IP addresses, I block about 10 000+ IP addresses, so every IP is like new rule. I don't know how fast it is, because let's say that someone DDoS me width bandwidth of some Gbps, can iptables handle it? CPU: 1 core of ...
DDoS me width bandwidth of some Gbps, can iptables handle it? Iptables can handle anything aslong as you give it enough resources to work with, and it will probably outlast your physical connection anyway. is possible to make iptables faster? For example that I would "bundle" all these IP addresses into 1 rule. This is...
1
1
5,378
2018-04-15T12:48:38.770
infrastructure
serverfault.com
245,707
Moving SQL server 2016 DB's from mirroring to HA
We have Windows Server 2016 machines with SQL server 2016 standard edition. Currently mirroring is implemented and now are planning to move to HA with 1 listener for each DB. We have multiple DB's In few DB stored procedure we have call to other DB with hardcode name. Once we move to HA with 1 listener for each DB, wil...
Since you are on standard edition - you will be using Basic Always On availability groups for a single database . Once we move to HA with 1 listener for each DB, will this new configuration be any issue for me? The only issue that I see is that you have to failover all the interrelated databases together (since your ap...
0
0
68
2019-08-19T19:19:21.213
database_errors
dba.stackexchange.com
314,553
Throw no default value error even if we give value
A user of one of my product is using [CODE] . This is the table creation: [CODE] When my product run : [CODE] It throw error: "Field 'reports' doesn't have a default value". This request works with all mysql versions that I tested for multiple years, so what's the new behavior and how can I fix it without breaking all ...
You probably have the [CODE] SQLMode variable set to true.
0
2
214
2022-07-18T18:55:24.837
database_errors
dba.stackexchange.com
62,018
crontab not running on VirtualBox unless I'm logged in
I am running Ubuntu Server 9.04 in VirtualBox on my work PC as a development environment. I have some scripts that I've put in my user's crontab that run throughout the day while I'm SSHed into the VM. Last night, I closed PuTTy and all of my other running applications (except for VirtualBox and the VM) and went home. ...
It would appear that you are trying to run a cron job as your user, and that you have some form of encrypted home directory set up. Your home directory (or some subset thereof) is unlocked and mounted when you log in, but when you are logged out, your home directory is unavailable, thus the error in your logs. You shou...
1
2
3,149
2009-09-03T15:05:43.507
infrastructure
serverfault.com
253,524
Can't understand on how to implement MVP/MVC for my software requirements
Recently I decided to start developing a client/service based system using WCF and a Duplex Channel (callbacks from Service to client). The clients will behave as "slaves", that is, they will only connect to server and from then on, only the server communicates with them. Eventually the server may request that the clie...
Patterns Abstract Details, not Vice Versa The clients will behave as "slaves", that is, they will only connect to server and from then on, only the server communicates with them. Eventually the server may request that the clients send "data streams ... MVC and MVP, ... don't seem to be designed to fulfill my specific r...
1
5
379
2014-08-16T12:52:30.137
api_errors
softwareengineering.stackexchange.com
1,148,903
How is the authentication token generated for the IBM Tivoli Netcool/OMNIbus ObjectServer REST API?
We have an application that sends a request to an IBM Tivoli Netcool/OMNIbus 8.1 server's ObjectServer REST API. It sends a GET request to [CODE] with the following HTTP headers: [CODE] The request works fine in our dev environment, and the REST API returns the requested alert information. However, in our test environm...
Anything can create the Basic authentication header. It is the base 64 encoded value of the [CODE] phrase. In your test environment, base64 encode the current [CODE] for the account you want to use, and add it to the header. You can use a site such as the following if you need a tool: https://base64decode.org/ https://...
1
2
62
2023-11-30T21:55:02.623
api_errors
serverfault.com
14,442
Can not install mysql client and server using a playbook Ansible
Do you know how I can fix this error? I'm getting 404 response from my node machibe when I'm trying to install default-mysql-client and server using Ansible-playbook apt module or shel. Facts I do can install another software like [CODE] , If I use the [CODE] option I'm getting the same error, but when I install the pa...
Maybe specify other package names that one can see at http://deb.debian.org/debian/pool/main/m/mariadb-10.3/ like: [CODE]
1
1
625
2021-08-04T12:27:15.853
database_errors
devops.stackexchange.com
12,433
Docker-compose containers can't connect to each other
According to the Docker Compose Docs: Networking : By default Compose sets up a single network for your app. Each container for a service joins the default network and is both reachable by other containers on that network, and discoverable by them at a hostname identical to the container name. For example, suppose your...
The Dockerfile specifies how a container image is built . The Dockerfile’s [CODE] command is trying to ping the [CODE] container, which is not yet running during the build phase. Once the container images have been created, compose will start the containers and they will be able to address each other via their service ...
0
7
4,549
2020-09-17T17:37:46.033
pipeline_ops
devops.stackexchange.com
899,364
netdata ipv4 UDP errors
I've recently installed netdata on an Amazon EC2 debian instance that I have. Netdata is pretty cool, nice charts/graphs, painlessly easy to install (compared to others.) A number of times each day I receive a message such as [CODE] and a few minutes later, a recovery message. There are probably hundreds of errors indi...
[CODE] uses [CODE] as the metrics collection system. This is a UDP based protocol which is incredibly fast and efficient, but at high rates can overflow the recv_buffer of the ingress node. The default receive buffer is around 1M - so if the statsd agent isn't able to consume quick enough to keep the buffer from fillin...
2
7
6,110
2018-02-28T17:20:36.627
pipeline_ops
serverfault.com
187,432
SSAS Cube processing randomly fails with 08S01 error
We have a cube which is scheduled to process every morning at 6:00 to run at SSAS 10.50.2500.0. Sometimes it does it ok. More often than not, it fails. When it happens, SQL Server has this entry in the log (XML beautified): [CODE] Where [CODE] and [CODE] are not always the same and once in awhile job finishes without a...
[CODE] is pretty clear. You have a TCP connectivity issue. Perhaps a configuration issue with either the local machine or the server. If SSAS is running on the same machine as SQL Server, you may be seeing resource exhaustion causing TCP to drop packets. Confirm you have the recommended TCP/IP stack settings configured...
2
1
2,394
2017-10-02T10:48:08.903
api_errors
dba.stackexchange.com
178,833
View Web Analytics reports in SharePoint Foundation 2010 Central Administration
I want to look at Web Analytics reports older than 30 days in SharePoint Foundation 2010. According to TechNet , I should be able to: Log onto Central Administration as a member of the Farm Administrators SharePoint group. In Central Administration, on the Home page, click Monitoring. On the Monitoring page, in the Rep...
According to the official feature comparison page , Web Analytics feature is only available in Standard and Enterprise editions. The page you are referencing also indicates this is a server feature not available in Foundation edition.
0
1
3,306
2010-09-07T16:07:14.630
pipeline_ops
serverfault.com
800,437
setup ssl with nginx on linux
I have this clients server where I would like to set up ssl on a site like this app..net The server is running ubunto and written in laravel / php. [CODE] This is my config file for my specifik site. Right now when I go to app..net I land on www..com, I have no idea what the problem is. EDIT: If i change the config fil...
From what I gather, your domain does not have a redirect from HTTP to HTTPS. This would explain that without listening on port 80 for that domain, NGINX would fall back to the default server which I assume to be your primary domain. In any case, if you want automatic HTTPS on the app..net, you should add app..net to th...
-1
0
59
2016-09-01T10:19:53.540
infrastructure
serverfault.com
48,108
Unique constraint across two columns
I need to add a constraint with two columns that says if any given value is present in one of the columns, then: 1) It cannot be duplicated in the same column. 2) It cannot be duplicated in the other column either. The constraint we are looking to make is with PrimaryEmail & SecondaryEmail . This would be invalid: [COD...
This isn't possible with the proposed table structure declaratively. You would need triggers to enforce this. A unique index on both columns, together with a pair of check constraints with scalar UDFs, gets quite close however. [CODE] The reason for [CODE] is to avoid problems with snapshot isolation . One problem with...
5
7
12,949
2013-08-14T06:12:47.983
data_quality
dba.stackexchange.com
125,029
make local only daemon listening on different interface (using iptables port forwarding)?
i have a daemon program which listens on 127.0.0.1:8000. i need to access it when i connect to my box with vpn. so i want it to listen on the ppp0 interface too. i've tried the "ssh -L" method. it works, but i don't think it's the right way to do that, having an extra ssh process running in the background. i tried the ...
I took a quick glance at your iptables rules, and my first thought is, that they look good. Are you sure, it doesn't work already - but only from a foreign host. If you try to connect to it from the server itself, it won't work. In that case, you'll also need to add your nat rule to the nat OUTPUT chain: [CODE] (This i...
0
1
1,310
2010-03-22T16:58:39.553
infrastructure
serverfault.com
544,462
Wireless Clients unable to connect to internet
Our small office network consists of 2 windows 2008 servers, and 14 workstations (8 running windows 7 and 6 running windows xp) and 1 router(wired/wireless). The main server has DHCP, DNS, Active directory configured. Server 2 acts as a backup server with AD replicated and DNS. DHCP has been disabled on the router so c...
Ensure that your DHCP server is assigning a valid default gateway, subnet mask, and/or name server(s). If it is not this, then please provide a brief explanation of your ip addressing scheme. (E.g. are all your clients and servers on the same subnet, and using the same gateway?)
0
1
261
2013-10-07T23:37:59.547
database_errors
serverfault.com
203,059
Why is Quicksort called "Quicksort"?
The point of this question is not to debate the merits of this over any other sorting algorithm - certainly there are many other questions that do this. This question is about the name. Why is Quicksort called "Quicksort"? Sure, it's "quick", most of the time, but not always. The possibility of degenerating to O(N^2) i...
In 1962 research on sorting algorithms wasn't as far advanced as today and the computer scientist Tony Hoare found a new algorithm which was quicker than the other so he published a paper called Quicksort and as the paper was quoted the title stayed. Quoting the abstract: A description is given of a new method of sorti...
9
13
6,279
2013-06-28T14:15:17.077
api_errors
softwareengineering.stackexchange.com
793,461
Why does changing data directory for PostgreSQL 9.5 in Server 2008 lead to "directory does not exist"?
I'm trying to migrate a PostgreSQL 9.5 database to a larger disk E on a Windows 2008 Server. After stopping the service I initially tried copying the the [CODE] folder to the new disk and then changed the PostgreSQL Service's executable path using [CODE] I changed the permissions on the [CODE] folder to include "Networ...
Found the problem while scanning through the Running & Installing PostgreSQL On Native Windows Wiki The PostgreSQL service account needs read permissions on all directories leading up to the service directory. It needs write permissions only on the data directory. I had set the write permission on the [CODE] directory ...
1
0
2,777
2016-08-02T20:04:57.650
database_errors
serverfault.com
915,004
IIS and SQL Server Performance Issues when not on same machine
Issue: Trying to get the same (or better) performance with a separate SQL Server 2017 and IIS 7.5 server than with having both on the same machine. Trying to move toward scalability for future growth. Using WebSurge to test the speen on the same box that's running both IIS and SQL Server 2017 Developer with 32gb of ram...
You should make sure the duplex settings on your nic's all match up. Always must have the same duplex setting, whether it's AUTO everywhere, or 1 Gbps Full duplex. This means checking the duplex setting on the nic's (network cards) of each server, as well as any hardware between them, like a switch. Next, I would run w...
1
0
1,900
2018-06-03T20:17:57.310
database_errors
serverfault.com
287,343
Granting select on syscat.schemata - DB2
I was wondering if it is safe to grant select rights to syscat.schemata to users on a DB2 database? What could go "wrong"? Some tool like DataGrip and DBeaver cannot load connection schemas because of this missing rights. Others tools like AQT or SquirrelSQL load schemas that they see with not problem. I am not really ...
Select privileges on all [CODE] objects are granted by default to the [CODE] pseudo-group (unless the database is created as "restrictive"), so you shouldn't have ended up with users not being able to access [CODE] unless you or someone before you chose to actively prevent that. What could go "wrong"? Users will be abl...
0
1
553
2021-03-19T16:00:45.440
warehouse_errors
dba.stackexchange.com
832,006
Identify failing or hanging outbound network connections on linux
I admin a busy webserver which uses nginx/php-fpm , connects out to mysql(RDS) and elasticsearch, but also many third parties for advertising and other plugins etc are on the site(unfortunately I’m not aware of all the specifics). I have a random, and intermittent issue plaguing me, occasionally php-fpm workers start t...
The only way you'll be able to get the required data is by doing a packet capture, with full packet details. Something like: [CODE] Warning, this will consume disk space, so ensure you have plenty of storage available for the packet capture. After running this through a period where the issue is observed, copy the file...
0
0
1,273
2017-02-11T13:26:51.977
pipeline_ops
serverfault.com
410,844
Amazon Micro Instance Crashed - Help Me Figure Out Why?
I am running an Amazon AWS Micro Linux Instance and it crashed during some "light" usage a few days ago. I am running an app that uploads photos to the server. We had maybe 10 users uploading multiple photos during a 1 hour period. At some point, the server stopped responding. I logged into the AWS Console and found th...
The Linux out-of-memory killer felt obliged to free some RAM. Which it then attempted to do (httpd being the logged target). However, it looks like it was not successful enough and ended up locking up hard, which would not get logged since the server was out of RAM and thus didn't have memory for log-buffers.
-2
5
759
2012-07-24T21:33:40.583
pipeline_ops
serverfault.com
189,634
How to serve dynamic pages outside the document root?
I'm trying to setup a simple web app and I'm having some difficulties. Here's how I have it setup : [CODE] I want Apache to serve everything in public_html if he can find it, else send the request to my application. a snippet of my virtual host file : [CODE] I'm really not sure about the ../application, (because I thin...
Alias comes to mind: [CODE]
0
1
2,180
2010-10-11T08:30:02.183
infrastructure
serverfault.com
818,806
HAProxy errors in configuration file
I am trying to configure [CODE] SSL using HAproxy but I get a lot of errors here my example error detected while parsing ACL [CODE] But I am getting following errors [CODE] I have tried to use code example from a lot of tutorials and articles even from official site, but each time I get parsing errors.
Thanks everyone for help. The problem was in ancient version of [CODE] . Because I've installed it using [CODE] . Version 1.4 2013 I have just compiled the recent version 1.7 from sources and it started fine. Thanks.
0
1
5,445
2016-12-05T13:59:44.203
infrastructure
serverfault.com
133,582
Architecting Challenge: How would you write an opensource script installer to run in a browser?
I currently have an installer that works, but I have to repackage the open source apps and hack things together to get the installer to install them. I want to be able to use the apps installation method without having to hack and repackage. So I am thinking about rewriting it. It will allow a user with little to no te...
You're not going to have the ability to execute scripts via FTP, obviously. But, you can upload a .PHP file into the user's web directory, and then remotely execute that PHP file (or whatever language you pick). Thats why we dont give world writable rights to directories where scripts are stored! :-) So, an approach on...
2
2
376
2012-02-06T17:34:59.137
api_errors
softwareengineering.stackexchange.com
38,982
List partitioning or filtering a non-partitioned table, which incurs lower cost?
Consider a list partitioned table [CODE] on column [CODE] , and non-partitioned table [CODE] also having the same columns. Assume all tables are adequately indexed. Set 1: [CODE] Total cost = [Cost to insert rows into partitioned table] + [Cost to pull data from a specific partition] 'Cost to insert rows into partition...
The performance benefits of partition pruning depend on the proportion of rows being selected from the table and the efficiency with which the rows can be isolated to their own partition(s). If you are selecting 5% of a table's rows and those rows are isolated into a subset of partitions then selecting them is generall...
0
1
542
2013-04-01T11:14:51.403
database_errors
dba.stackexchange.com
1,000,775
first step to combat display name spoofing on postfix
lately we receive a lot of display name spoofed emails in our company, impersonating customers and suppliers. Since my co-workers unfortunately do not pay too much attention to security warnings, etc. I could not rely on them being aware of the threat. I searched on Google for hours didn't find a satisfying solution to...
I was having this issue on our company mail server, since we validate our own email domain, only login users can send as from, therefore, I modified your syntax a little bit [CODE] this way, the email receiver can know who the sender is. Your code might cause false positive if some lazy company users set the from name ...
1
1
968
2020-01-28T15:27:00.867
infrastructure
serverfault.com
50,185
SQL Server WHERE clause on CLR method (spatial) peformance
I have a query that joins to a table containing 2 million rows and need to filter on its geometry column by its geometry type (using geom.STGeometryType()). The query takes less than a second to run without this WHERE clause but over 40 seconds to run with the WHERE clause. The execution plan seems to indicate that the...
The first thing to look at is your indexing strategy. Bad execution plans are often caused by insufficient indexes or stale statistics. Your statistics warning might hint at that. If that does not resolve your problem there are a few hacks that you can try: A top operation requires SQL Server to separate query sections...
4
3
909
2013-09-19T10:25:03.793
database_errors
dba.stackexchange.com