Category Archives: Linux

This is where all my linux pages will live.

Basic GIT stuff

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

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

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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WordPress Stuff

To change the admin username in WordPress: 1)Go into your phpmyadmin, and click on “Databases.” 2)Click on the name of your database. 3)Click the “Browse” icon next to wp_users. 4)Click the edit icon next to admin – should be first … Continue reading

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Regular Expression Notes

Explaining the following regular expression: (\d(3,4)[.-]?)+ ( starts a capturing group \ escapes the following character d end character shorthand (match any digit in the range 0 through 9 with \d) { open qualifier 3 minimum quantity to match , … Continue reading

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Diagnosing SSL received a record that exceeded the maximum permissible length

If you setup an ssl cert but are getting the following: SSL received a record that exceeded the maximum permissible length. 1) Check that netstat -ntlp shows httpd listening on 443 2) Check that port 443 is open in iptables … Continue reading

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Overriding php.ini values locally

php directives are listed here: http://www.php.net/manual/en/ini.list.php Modes determine when and where a PHP directive may or may not be set. This is explained here: http://www.php.net/manual/en/ini.list.php A virtual host may be configured to use a local php.ini file in place of … Continue reading

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MySQL Replication Tools

If replication stops and the slave status shows: Last_Errno: 1580 Last_Error: Error ‘You cannot ‘ALTER’ a log table if logging is enabled’ on query. Default database: ‘mysql’. You need to skip over a bad query as follows: mysql> SET GLOBAL … Continue reading

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MySQL went away errors

This means that the server timed out and closed the connection. Two most common reasons (and fixes) for the MySQL server has gone away (error 2006) are: Your wait_timeout variable in your MySQL my.cnf configuration file is not large enough. … Continue reading

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Creating multiple chroots

Edit the /etc/ssh/sshd_config: 1. Comment out the Subsystem sftp line 2. Create line as follows: Subsystem sftp internal-sftp 3. Add the following at the bottom of the sshd_config file: Match Group sftponly ChrootDirectory %h X11Forwarding no AllowTCPForwarding no ForceCommand internal-sftp … Continue reading

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