git: create a remote repository
If you have a local repository and want to create your own remote git repository as a backup (or share your work with others, here's what you need to do:…
apache: fixing ‘config variable XX is not defined’ error
PROBLEM: You try to execute from a shell some apache command like this: # apache2 -t -D DUMP_MODULES and you get the following error messages: AH00111: Config variable ${APACHE_LOCK_DIR} is…
mysql: ‘%’ doesn’t match localhost and/or hostname
PROBLEM: You granted access privileges to a user connecting from anywhere using this command: mysql> GRANT ALL PRIVILEGES ON *.* TO prueba@'%' IDENTIFIED BY 'password' Then, when you try to…
samba troubleshooting
WARNING: Ignoring invalid value 'share' for parameter 'security' The value 'share' for paramater 'security' is no longer valid for recent versions of Samba, so if you were running an older…
git configuration files
There are three levels of configuration in git: System Values defined at this level will apply to all users. The values are stored in /etc/gitconfig Global Values defined at the…
Cassandra troubleshooting
Execution of 'nodetool status' fails Common error messages: Error: Could not find or load main class Error opening zip file or JAR manifest missing : /usr/local/bin/../ Error occurred during initialization…
Remove a linux RAID device
1. Find the devices associated with the RAID device mdadm --detail <raid_device> The last lines of output of the above command shows the associated devices (see the example below). 2.…
git: clone a repository without the project folder
When you clone a remote repository, a folder with the name of the project is created in your local working directory and then the contents of the repository is copied…
MySQL cheatsheet
Show MySQL configuration settings mysql> SHOW VARIABLES; Show MySQL running threads mysql > SHOW PROCESSLIST; Check the status of the tables of a database $ mysqlcheck -c <database>
Setting up software RAID on a running Debian system
If you have a running Debian (or any Debian based distro, like Ubuntu) system and want to configure a RAID1 (mirror) without losing your existing data, this can be accomplished…