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1500 questions
68
votes
13 answers

Install a newer version of Git on CentOS 7

I like to enable Git "Push to Deploy" on my CentOS 7 server. Currently I only can get Git 1.8.3.1 via yum. I need a newer version. Do I have to build it from source or is there any repo I can use? I alreay added EPEL and elrepo but yum still gives…
Oliver
  • 791
68
votes
2 answers

Nginx location regex doesn't work with proxy pass

I'm trying to get these 2 location directives working in Nginx but I'm getting some errors back when booting Nginx. location ~ ^/smx/(test|production) { proxy_pass http://localhost:8181/cxf; } location ~ ^/es/(test|production)…
Niels
  • 841
68
votes
2 answers

Can we have multiple CNAMES for a single Name?

I need this for load balancing. For example, I've two azure storage accounts (say a and b) and the blob addresses for those are a.blob.core.windows.net and b.blob.core.windows.net. Both of them store identical data. Now I need to provide a single…
68
votes
12 answers

MySQL keeps crashing: InnoDB: Unable to lock ./ibdata1, error: 11

I have a simple webserver (Debian 6.0 x86, DirectAdmin with 1 GB of memory and still 10 GB free space, mySQl version 5.5.9), however the mySQL server keeps crashing and I need to kill all mySQL processes to be able to restart it…
Devator
  • 1,513
68
votes
6 answers

What is the difference between a managed and unmanaged switch?

I've seen some documentation discussing the use of an unmanaged switch. What is the difference in functionality/performance/etc. between an unmanaged and managed switch?
Luke
  • 2,123
68
votes
19 answers

How to ping in linux until host is known?

How can I ping a certain address and when found, stop pinging. I want to use it in a bash script, so when the host is starting up, the script keeps on pinging and from the moment the host is available, the script continues...
68
votes
5 answers

associate name with ip for ssh?

Let's say I just have an ip address for a server and I don't have a domain with it (it's just a database server, so it doesn't need a domain). I don't want to have to remember the ip address every time, so is there a way I could still use the syntax…
Matthew
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68
votes
3 answers

GNU less: How can I search while ignoring case sensitivity without using less -I option?

From GNU less manpage -i or --ignore-case Causes searches to ignore case; that is, uppercase and lowercase are considered identical. This option is ignored if any uppercase letters appear in the search pattern; in other words, if a pattern contains…
Tom Feiner
  • 18,598
67
votes
9 answers

What a beginner should know/learn for sysadmin job?

This is a Canonical Question about System Administration Careers When I start my job as System Administrator, what basics skills should I know/learn? Are there any key differences for Network, Storage, Database, and other Administrators?
Dhanapal
  • 905
67
votes
4 answers

loginctl enable-linger/disable-linger ... but reading linger-status?

I know how to enable/disable lingering with loginctl. But up to now I found no way to query the status of a user. I want to know: Is lingering enable for user foo? How can I access this information?
guettli
  • 3,811
67
votes
4 answers

How to manage DNS in NetworkManager via console (nmcli)?

I have CentOS 7.2 (guest in VirtualBox, vagrant box centos/7, no GUI). I see there is a nameserver in file: $ cat /etc/resolv.conf # Generated by NetworkManager nameserver 10.0.2.3 But how to add or replace with new one? I have done this manually…
Kirby
  • 1,139
67
votes
4 answers

What characters should I use or not use in usernames on Linux?

I want to create user accounts named after a domain name. adduser complains that the usernames need to match the NAME_REGEX regular expression. adduser: Please enter a username matching the regular expression configured via the NAME_REGEX…
Ed Haber
  • 825
67
votes
3 answers

Rsync triggered Linux OOM killer on a single 50 GB file

I have a single 50 GB file on server_A, and I'm copying it to server_B. I run server_A$ rsync --partial --progress --inplace --append-verify 50GB_file root@server_B:50GB_file Server_B has 32 GB of RAM with 2 GB swap. It is mostly idle and should…
dataless
  • 833
67
votes
4 answers

What is the difference between syslog, rsyslog and syslog-ng?

I am a bit confused in syslog, rsyslog and syslog-ng. From where can I get the source code for syslog()? Is there any difference between rsyslog and rsyslogd?
StackUser
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67
votes
3 answers

Is a VM with 2 CPUs really faster than one with 4 CPUs?

Our IT created a VM with 2 CPUs allocated rather than the 4 I requested. Their reason is that the VM performs better with 2 CPUs rather than 4 (according to them). The rationale is that the VM hypervisor (VMWare in this case) waits for all the…
AngryHacker
  • 2,897