[BlueOnyx:06219] Re: Increasing disk capacity using RAID rebuilds

[Dogsbody]

> Is there any way to increase the disks in use on a live server without a
> complete rebuild and transferring all the sites?

Increasing (as in growing) isn't possible without downtime.

> I am hoping it would be possible to do something like swap secondary
> RAID disks to the larger capacity, let it rebuild, move this to primary,
> put another large disk is as secondary and rebuild again.
> I've tried this on a test server, but I cannot find how to get linux to
> see the larger disks or the extra capacity beyond the size of the
> original disk size. I guess this is possible, but I've missed an
> important step somewhere.

This is done from memory and notes on BQ so specifics may be slightly 
different  :-)

Resizing /home (to 300GB) (requires shutting down services)
=========================================================
* vgchange -a y
* /etc/init.d/dovecot stop
* /etc/init.d/helix stop
* /etc/init.d/httpd stop
* /etc/init.d/mt-daapd stop
* /etc/init.d/mysqld stop
* vi /etc/ssh/sshd_config
  PermitRootLogin yes
* /etc/init.d/sshd restart
* # Log in directly as root and close old ssh
* umount /home
* e2fsck -f /dev/mapper/VolGroup00-LogVol04
* lvextend -L300G /dev/VolGroup00/LogVol04
* resize2fs -p /dev/mapper/VolGroup00-LogVol04
* e2fsck -f /dev/mapper/VolGroup00-LogVol04
* mount /home
* /etc/init.d/dovecot start
* /etc/init.d/helix start
* /etc/init.d/httpd start
* /etc/init.d/mt-daapd start
* /etc/init.d/mysqld start
* vi /etc/ssh/sshd_config
  PermitRootLogin without-password
* /etc/init.d/sshd restart

Adding a new (100GB) volume in the empty space
==============================================
* lvcreate -L100G -nLogVol05 VolGroup00
* mkfs -t ext3 /dev/mapper/VolGroup00-LogVol05
* mkdir /home2
* vi /etc/fstab
  /dev/VolGroup00/LogVol05    /home2    ext3    defaults        1 2
* mount /home2

You can then move things to home2 and sym link things there from it's 
old location.

I hope this helps

Dan