[DRBD-user] On-line device growing quirk

[Luis Garrido]

Hi!

I have been testing the on-line growing as described at:

http://www.drbd.org/users-guide-emb/s-resizing.html

The backing device is a LVM logical volume and the filesystem is ext3.

The method works fine, but I have to bring down and up the device
twice (!) so the change in size is detected.

I have tried to wait for what I consider time enough (10 minutes for a
resize of 100 MB) for synchronization but it won't change anything.
The only way I have found to make the system aware of the resizing is
the one I described.

I have pasted the commands for the resizing session at the end of the message.

Is this a known issue? I have tried to search the web, but I couldn't
find anything. Is there a more elegant workaround?

Cheers,

L



[root at cluster11 ~]# modinfo drbd | grep v8
description:    drbd - Distributed Replicated Block Device v8.0.7

[root at cluster11 ~]# uname -r
2.6.18-92.1.1.el5.028stab057.2

[root at cluster11 ~]# rpm -q drbd82
drbd82-8.2.6-1.el5.centos

[root at cluster11 ~]# lvs
  LV     VG   Attr   LSize Origin Snap%  Move Log Copy%  Convert
  ovz101 vgla -wi-ao 1.90G

[root at cluster11 ~]# echo $(( $(blockdev --getsize64 /dev/drbd101) /
1024 / 1024 ))
1947

[root at cluster11 ~]# lvresize -L 2.9G /dev/vgla/ovz101
  Rounding up size to full physical extent 2.90 GB
  Extending logical volume ovz101 to 2.90 GB
  Logical volume ovz101 successfully resized

[root at cluster12 ~]# lvresize -L 2.9G /dev/vgla/ovz101
  Rounding up size to full physical extent 2.90 GB
  Extending logical volume ovz101 to 2.90 GB
  Logical volume ovz101 successfully resized

[root at cluster11 ~]# drbdadm resize ovz101

[root at cluster11 ~]# echo $(( $(blockdev --getsize64 /dev/drbd101) /
1024 / 1024 ))
1947

[root at cluster11 ~]# cat /proc/drbd
version: 8.0.7 (api:86/proto:86)
GIT-hash: cf14288833afe95db396075f8530a5960d29e498 build by
phil at mescal, 2007-11-02 13:15:41

101: cs:Connected st:Primary/Secondary ds:UpToDate/UpToDate C r---
    ns:0 nr:0 dw:0 dr:8 al:0 bm:0 lo:0 pe:0 ua:0 ap:0
        resync: used:0/31 hits:0 misses:0 starving:0 dirty:0 changed:0
        act_log: used:0/257 hits:0 misses:0 starving:0 dirty:0 changed:0

[root at cluster11 ~]# drbdadm down ovz101
[root at cluster11 ~]# drbdadm up ovz101
[root at cluster11 ~]# drbdadm primary ovz101
[root at cluster11 ~]# echo $(( $(blockdev --getsize64 /dev/drbd101) /
1024 / 1024 ))
1947

[root at cluster11 ~]# drbdadm down ovz101
[root at cluster11 ~]# drbdadm up ovz101
[root at cluster11 ~]# drbdadm primary ovz101
[root at cluster11 ~]# echo $(( $(blockdev --getsize64 /dev/drbd101) /
1024 / 1024 ))
2971

[root at cluster11 ~]# resize2fs /dev/drbd101
resize2fs 1.39 (29-May-2006)
Resizing the filesystem on /dev/drbd101 to 760799 (4k) blocks.
The filesystem on /dev/drbd101 is now 760799 blocks long.