Vicky’s server guides

After OS upgrades and updates it is needed to run EnsimX through maintenance mode. Here is info how to do it:

/usr/local/sbin/set_maintenance
/usr/local/sbin/set_pre_maintenance
/usr/local/sbin/set_post_maintenance
/etc/init.d/epld restart

If you encounter any problems you can exit the maintenance mode by issuing this command:

/usr/local/sbin/exit_post_maintenance

When you experience error during EnsimX import script like this:

Unknown Error: Traceback (most recent call last):
File “vhbackuplib.py”, line 54, in call_backend_import
File “virtualhosting/virthost.py”, line 4575, in vhimport
File “virtualhosting/virthost.py”, line 4730, in __do_import
File “virtualhosting/virthost.py”, line 5030, in __site_import
File “virtualhosting/virthost.py”, line 3300, in handle_remaining_files
File “virtualhosting/virthost.py”, line 3380, in link
OSError: [Errno 17] File exists

the cause may be in X11 symlink on OS other than FC6. The cure is as follows:

mv /home/virtual/FILESYSTEMTEMPLATE/siteinfo/usr/lib/X11{,XTEMP}
vhimport site_backup.tar.gz
mv /home/virtual/FILESYSTEMTEMPLATE/siteinfo/usr/lib/XTEMP{,X11} 

Basicaly what is does it renames /home/virtual/FILESYSTEMTEMPLATE/siteinfo/usr/lib/X11 and after the restore is successful it renames it back to original name.

The file to rebuild is located in /usr/lib/opcenter/sendmail/install/sendmail.mc

Make sure you do backups first:

cp /usr/lib/opcenter/sendmail/install/sendmail.mc /usr/lib/opcenter/sendmail/install/sendmail.mc.bak

After editing the file /usr/lib/opcenter/sendmail/install/sendmail.mc you need to rebuild it to macro format which will be located in /etc/mail/sendmail.cf

m4 /usr/lib/opcenter/sendmail/install/sendmail.mc > /etc/mail/sendmail.cf

voila! it is done, now restart sendmail by “service sendmail restart” and your changes are applied.

Michael Boelen, the author of RKHUNTER rootkit checker has made another nice auditing tool – Lynis. It works on many Linux/Debian/MacOS/BSD systems and provides you the admin important information about system configuration and security issues.

Update: On 5th April 2009 there was version 1.2.6 released. I updated this how-to.

Read the rest of this entry »

I recently got to administer a few linux boxes and wondered why vi does not show colors when I edit files. Some servers did it, some did not. It was differently set up by datacenter images and I really did not have time to investigate.

Now it just annoyed me because I could not find few syntax errors on one server and here is the solution.

Open up some file in vi or vim and hit ESC, then type “:syntax on”  and the magic happens… let there be color

If you do like it without color, type “:syntax off”

Rkhunter is an intrustion detection program for Linux OS which has been widely used by many server administrators. Sometimes there is a false alarm but most of the time you need to check the problematic areas Rkhunter points out.

NEW: December 31st 2008 – Rkhunter v.1.3.4. is available and this how-to is updated.

Read the rest of this entry »

Here is how I speed up apache by compressing pages with mod_deflate module and setting higher cache expiration times in mod_expires module. Here is how… Read the rest of this entry »

Ever wondered how to find out your mysql root password? Well, on Ensim server it is easy to find out.

ensim-python -c “import sys;sys.path.append(\”/usr/lib/opcenter/mysql\”);import mysqlbe;print mysqlbe.read_mysqlpass()”

It it one line command. Execute it from shell logged in as root. Works well

Ever wondered how to disable the email alert sent when cron is executed? Easy help, there are various ways to achieve this, so feel free to use the one you like the best. They all work, though. Read the rest of this entry »