[CentOS] is it safe to resize root, on an LVM system, online?

[Rudi Ahlers]

On Sun, Jul 11, 2010 at 8:39 PM, Digimer <linux at alteeve.com> wrote:
> On 10-07-11 02:27 PM, Rudi Ahlers wrote:
>> Hi,
>>
>> One of our servers has a too small root partition on LVM and needs to
>> be resized. Can / be safely increased online, without a reboot?
>>
>> [root at zaxen02 ~]# lvscan
>>    ACTIVE            '/dev/LVM01/root' [4.00 GB] inherit
>>    ACTIVE            '/dev/LVM01/home' [20.00 GB] inherit
>>    ACTIVE            '/dev/LVM01/var' [4.00 GB] inherit
>>    ACTIVE            '/dev/LVM01/swap' [4.00 GB] inherit
>>    ACTIVE            '/dev/LVM01/log' [1.00 GB] inherit
>>    ACTIVE            '/dev/LVM01/webmin' [2.00 GB] inherit
>>    ACTIVE            '/dev/LVM01/xenstored' [2.00 GB] inherit
>>    ACTIVE            '/dev/LVM01/xensave' [2.00 GB] inherit
>>    ACTIVE            '/dev/LVM01/opennation-net_img' [10.00 GB] inherit
>>    ACTIVE            '/dev/LVM01/opennation-net_swap' [1.00 GB] inherit
>>    ACTIVE            '/dev/LVM01/pluto_img' [100.00 GB] inherit
>>    ACTIVE            '/dev/LVM01/pluto_swap' [1.00 GB] inherit
>>    ACTIVE            '/dev/LVM01/tmp' [5.00 GB] inherit
>> [root at zaxen02 ~]# pvscan
>>    PV /dev/md1   VG LVM01   lvm2 [232.69 GB / 76.69 GB free]
>>    Total: 1 [232.69 GB] / in use: 1 [232.69 GB] / in no VG: 0 [0   ]
>> [root at zaxen02 ~]#
>
> It depends mainly on the filesystem you are using. The ext[3|4]
> filesystems are fine. You'll have to extend the LV, and then separately
> extend the filesystem itself.
>
> Please test this on a non-production server before trying it on your
> live server, just to be safe and to be sure that you've got your syntax
> right.
>
> --
> Digimer
> E-Mail:         linux at alteeve.com
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> _______________________________________________


The server runs on CentOS 5.5 with ext3 (don't trust ext4 yet). I
don't have a test server setup for this, but it's a good idea to setup
one with a similar partition layout and try it there first :)

I just wanted to know whether it's safe for root to be resized without
a reboot or not.


-- 
Kind Regards
Rudi Ahlers
SoftDux

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