ISPConfig 3, Debian 7 - high load

Till,
How to do that?
Will it affect anything?
These are the partitions:

 

Resizing partitions with data always has a small risk of data loss. In addition you'd have to move the extended / swap partition first because you cannot resize the other partition otherwise.
Maybe it would be easier to create a new partition on the free space and copy all the /var content to it, then mount it as /var in linux. If this is suitable depends on your data structure (sizes of /home, /var etc.)

 

@Croydon
And that would work?
It won't mess up my ISPconfig configuration?
If yes, can you help me do that? Do I need to be physically by the server?

 

Moving a system path on a running system can always be tricky. The steps themselves are quite easy, but you should have a rescue system ready in case you have to revert things, when they go south.

1. Create a new ext4 partition in the free space
2. Mount new partition to e. g. /vartemp
3. Sync all data to the new partition mount
   e. g. with
   rsync -av --delete --progress /var/ /vartemp/
4. Stop important services, that use /var (e. g. apache, mysql)
   
5. Sync again with the same command to be sure you have latest data there
6. Unmount /vartemp
7. Move /var to /varold
   
8. Mount /var to the new partition (don't forget to add the entry to /etc/fstab!!!)
   
9. Check if everything is there (log path, web paths etc.)
10. Reboot the server and check that everything is working correctly.

Again: If things go wrong, you will need a rescue system you can boot into, to revert the steps.

 

@Croydon
Thank you very much, even if it's several months overdue.
I finally did this and everything works great. I just have some questions.
I added

Code:

/dev/sda3       /var     ext4    defaults    0 0

to /etc/fstab.
Is that ok or should I add something like this:

Code:

/dev/sda3       /var               ext4    errors=remount-ro,usrjquota=quota.user,grpjquota=quota.group,jqfmt=vfsv0 0       1

in accordance to the Perfect Server documentation:
https://www.howtoforge.com/perfect-server-debian-wheezy-nginx-bind-dovecot-ispconfig-3-p4

?