[CentOS] Resizing est4 filesystem while mounted

Mon Jun 18 20:28:31 UTC 2012
Dennis Jacobfeuerborn <dennisml at conversis.de>

On 06/18/2012 10:09 PM, Jeff Boyce wrote:
> Replying to the daily digest, with my response at the bottom.
> 
> 
> 
>> Message: 13
>> Date: Fri, 15 Jun 2012 12:22:08 -0700
>> From: Ray Van Dolson <rayvd at bludgeon.org>
>> Subject: Re: [CentOS] Resizing est4 filesystem while mounted
>> To: centos at centos.org
>> Message-ID: <20120615192207.GA23689 at bludgeon.org>
>> Content-Type: text/plain; charset=us-ascii
>>
>> On Fri, Jun 15, 2012 at 12:10:09PM -0700, Jeff Boyce wrote:
>>> Greetings -
>>>
>>> I had a logical volume that was running out of space on a virtual 
>>> machine.
>>> I successfully expanded the LV using lvextend, and lvdisplay shows that 
>>> it
>>> has been expanded. Then I went to expand the filesystem to fill the new
>>> space (# resize2fs -p /dev/vde1) and I get the results that the 
>>> filesystem
>>> is already xx blocks long, nothing to do. If I do a # df -h, I can see 
>>> that
>>> the filesystem has not been extended. I could kick the users off the VM,
>>> reboot the VM using a GParted live CD and extend the filesystem that way,
>>> but I thought that it was possible to do this live and mounted? The RH 
>>> docs
>>> say this is possible; the man page for resize2fs also says it is possible
>>> with ext4. What am I missing here? This is a Centos 6.2 VM with an ext4
>>> filesystem. The logical volumes are setup on the host system which is 
>>> also
>>> a Centos 6.2 system.
>>
>> Try resize4fs (assuming your FS is ext4).
>>
>> Ray
> 
> Well, I have never seen a reference to resize4fs before (and yes my FS is 
> ext4).  It is not on my Centos 6.2 system, and doing a little searching 
> through repositories for that specifically, or e4fsprogs, and I can't find 
> it anywhere to even try it.  Any google reference seems to point back to 
> resize2fs.  I ended up booting a live SystemRescueCD and using GParted via 
> the GUI.  My notes indicate that is what I had done previously also.  I am 
> still stumped, everything that I have read indicates that resize2fs can do a 
> live resizing on ext4 file systems.  Can anybody confirm or deny this?  Is 
> the reason I can't do this because it is on an LVM logical volume?  Thanks.

Please post some details about your storage topology. Without this
information its not really possible to be sure what is going on.
resizefs cannot work as long as the underlying layers don't see any change
in size and you didn't seem to look for that.

Regards,
   Dennis