====== Administration Tips ======

===== Restarting All Courier Services in one shot =====

<file>
root@mail:~# find /etc/init.d/|grep courier|while read line; do $line restart; done
</file>

===== Restarting all 3CX services in one shot =====

<file>
root@3cxserver:~# systemctl |grep 3CX|cut -f1 -d" "|while read line; do systemctl restart $line; done
</file>

===== Generate a random MAC Address =====

<file>
openssl rand -hex 6 | sed 's/\(..\)/\1:/g; s/.$//'
</file>

===== How to flush tinydns/dnscache =====

Some people say using
<file>
svc -du dnscache
</file>

will flush the dns cache. However, I have never had any such luck and must use the following
<file>
svc -t dnscache
</file>

===== Rsync complete filesystem =====

Sometimes I find myself in need of migrating a complete system into a VM or Container. Here is a pretty easy way to minimize downtime later.

<file>
rsync -aAHXv /* root@host.domain.tld:/var/lib/vz/private/115 --exclude={/dev/*,/proc/*,/sys/*,/tmp/*,/run/*,/mnt/*,/media/*,/lost+found}
</file>

As you can see above I am syncing to an OpenVZ container.

===== Move a running process to the background =====

This method cleanly moves a running process to the background and ensures you don't lose it when you log out of the session.

<file>
CTRL+z
bg
disown -h
</file>

Enjoy