Category Archives: Linux

This is where all my linux pages will live.

How to determine the RHEL version

Posted on April 10, 2015 by vicki

[root@vickistan ~]# cat /etc/redhat-release CentOS release 6.6 (Final) If that doesn’t produce results, try this: [root@vickistan ~]# lsb_release -i -r Distributor ID: RedHatEnterpriseServer Release: 5.5

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How to check the version of an installed package

Posted on January 27, 2015 by vicki

Ubuntu: dpkg -s PKGNAME Red Hat: rpm -q PKGNAME Arch Linux: pacman -Si PKGNAME

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Systemd

Posted on December 22, 2014 by vicki

This is how to stop a running service temporarily: # systemctl stop servicename.service This stops it from starting at boot, but does not stop a running service: # systemctl disable servicename.service That also prevents it from being started by anything … Continue reading →

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MySQL Indexing Stuff

Posted on November 20, 2014 by vicki

#Determine whether a table is indexed show index from [table name] #Display a table’s index mysql> show index from mysql.user; +——-+————+———-+————–+————-+———–+————-+———-+——–+——+————+———+—————+ | Table | Non_unique | Key_name | Seq_in_index | Column_name | Collation | Cardinality | Sub_part | Packed | … Continue reading →

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How to create a local yum repository

Posted on November 14, 2014 by vicki

Yum Server Side Take a look at the available repositories with the repolist option to yum: $yum repolist Loaded plugins: fastestmirror Loading mirror speeds from cached hostfile epel/metalink | 13 kB 00:00 * base: mirror.symnds.com * epel: epel.mirror.constant.com * extras: … Continue reading →

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Understanding rpm Verify output

Posted on November 14, 2014 by vicki

rpm -V output: S file Size differs M Mode differs (includes permissions and file type) 5 MD5 sum differs D Device major/minor number mismatch L readLink(2) path mismatch U User ownership differs G Group ownership differs T mTime differs

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Differences in useradd command in different Linux Distributions

Posted on November 5, 2014 by vicki

In Ubuntu and Debian: By default, each user in Debian GNU/Linux is given a corresponding group with the same name. In RedHat/CentOS,Gentoo If not specified, the behavior of useradd will depend on the USERGROUPS_ENAB variable in /etc/login.defs. If this variable … Continue reading →

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Basic GIT stuff

Posted on October 24, 2014 by vicki

Git stuff Conceptual description: http://www.sbf5.com/~cduan/technical/git/git-1.shtml **HEAD is the name given to the commit from which the working tree’s current state was initialized. git rebase allows you to pull changes from master into your development branch, but leave all of your … Continue reading →

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Lsyncd installation and configuration

Posted on January 22, 2014 by vicki

Overview This article describes how to use lsyncd as a sync’ing mechanism for multiple web servers data directories. This is only one scenario in which this program could be very useful for our customers. These notes will provide instructions on … Continue reading →

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Allow ssh only as a single user or from specific IPs

Posted on January 14, 2014 by vicki

The following are the relevant config bits in /etc/ssh/sshd_config # disable password authentication globally PasswordAuthentication no Either by username: # now re-enable it down at the very end of the sshd_config file like thus Match User rack PasswordAuthentication yes or … Continue reading →

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