[DRBD-user] Axigen LVM DRBD config problem

Docharkhehsaz m.docharkhehsaz at gmail.com
Wed Oct 27 14:40:49 CEST 2010

Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.

I was using default partitioning of centos,
So I "did shrink! " the file system using

· lvm vgchange --a y

·          e2fsck -f /dev/VolGroup00/LogVol00

·          resize2fs /dev/VolGroup00/LogVol00 420G

·          lvm lvreduce --L420G /dev/VolGroup00/LogVol00

command in rescue mode,
then I created a new lv named LogVol03 which is in VolGroup00 with size 420G

I used the  disk /dev/VolGroup00/LogVol03

And my problem had been solved,
All createing , attaching , and syncing went well.
Then I mounted /dev/drbd0 as /var/opt/axigen
Here is another question,

Do I have wasted my 420G space doing this?
Or better, how much space should I dedicate to / (root) partition and 
how much for drbd0? (/dev/VolGroup00/LogVol03) for best performance?

Thanks again for your replies.

On 2010/10/27 12:44 ???, Felix Frank wrote:
> On 10/27/2010 11:04 AM, Thomas Baumann wrote:
>> Hi,
>> so just do what the message says: zero the metadata on the underlying
>> storage:
>> dd if=/dev/zero of=/dev/VolGroup00/LogVol00 bs=1M count=1
>> This should help.
>> Best regards,
>> Thomas.
> Hi,
> it appears the OP would like his 900G filesystem not destroyed ;)
> So no, you might not want to do that.
>  From what I can see, you probably want to use external metadata. Can you
> shrink one of your LV's to make room for an additional dedicated
> metadata disk? Least pain that way.
> Alternatively, just shrink the fs in /var/opt to make room for the
> metadata. Are these mailservers in a failover cluster? If you can take
> them down for maintenance one at a time, you should be able to modify
> the filesystems.
>>> Should I use
>>> http://www.drbd.org/users-guide/s-lvm-lv-as-drbd-backing-dev.html
>>> Mean Should I create a lvm device then I map drbd device on it.
> You are trying this already, as far as I can tell from your config.
>>> Is there any way that I donot change the partition table,
>>> Mean I donot change size of any partition. or create any partition?
>>> An other question:
>>> What should I place in "disk /dev/VolGroup00/LogVol00;" should I use
>>> 'disk /sdb2" or "disk /sda2"
> I don't fully understand your layout. Does your PV comprise /dev/sda2?
> Is /dev/sdb2 used at all atm?
>>> I just wnat to have a mirror of /var/opt directory
> What is currently mounted as /var/opt.
> The current partition of /var/opt should become your backing device,
> then mount /dev/drbd0 as /var/opt.
> HTH,
> Felix

Mohammad Docharkhehsaz,
ITExpert , Network Administrator,
Imen Pardaz Azar

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.linbit.com/pipermail/drbd-user/attachments/20101027/8bc84166/attachment.htm>

More information about the drbd-user mailing list