[DRBD-user] DRBD offline resize problem

Roland Gsell roland.gsell at siedl.net
Tue Mar 17 14:45:00 CET 2015

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

Hi there,

I'm new to DRBD and I tried to resize a DRBD resource recently, but in the end the machine didn't startup afterwards (can't find boot device).

Maybe someone can tell me what I did wrong.

These are the steps taken:

1.) I used blockdev on the primary node to find out the sector size.

2.) drbdadm down vm_termubuntusrv

The next steps (3.) are just to dump the metadata. The command 3.4 didn't work right away (Found meta data is "unclean", please apply-al first), so I did it the hard way:

3.1) drbdsetup new-resource vm_termubuntusrv

3.2) drbdsetup new-minor vm_termubuntusrv 14 0

3.3) drbdmeta 14 v08 /dev/vg_raid5/vm_termubuntusrv internal apply-al

3.4) drbdadm dump-md mailsrv > /root/ubuntu_metadata.nodeMaster

3.5) drbdsetup attach 14 /dev/vg_raid5/vm_termubuntusrv /dev/vg_raid5/vm_termubuntusrv internal --on-io-error=detach --fencing=resource-only --disk-flushes=no --md-flushes=no --al-extents=1237 --c-delay-target=20 --c-fill-target=0 --c-max-rate=150M –c-min-rate=5M

3.6) drbdsetup connect vm_termubuntusrv ipv4: ipv4: --congestion-fill=400M --congestion-extents=800 --on-congestion=pull-ahead --ko-count=6 --protocol=A --cram-hmac-alg=sha1 --shared-secret=FooFunFactory --max-buffers=131072 --max-epoch-size=20000 --sndbuf-size=0 --rcvbuf-size=0 –verify-alg=md5

4.) drbdadm down vm_termubuntusrv

Do the actual resize:

5.) lvextend -L+5G /dev/vg_vms/vm_termubuntusrv

6.) root at backupsrv:~# drbdadm up vm_termubuntusrv 

Moving the internal meta data to its proper location 

Internal drbd meta data successfully moved. 

No usable activity log found. Do you need to create-md? 

Error ignored, no need to apply the AL

7.) I set the Node on primary to get the new sector size with blockdev

8.) change the „la-size-sect“ to the new size on both nodes

9.) make sure the resource is down on both nodes


root at mastersrv:~# drbdmeta_cmd=$(drbdadm -d dump-md vm_termubuntusrv) 

root at mastersrv:~# ${drbdmeta_cmd/dump-md/restore-md} /root/ubuntu_metadata.nodeMaster.neu 

Valid meta-data in place, overwrite? 

[need to type 'yes' to confirm] yes 

initializing with defaults 

Successfully restored meta data

11.) drbdadm up vm_termubuntusrv

12.) drbdadm primary vm_termubuntusrv

The command 2-6 and 8-11 were done on both nodes.

At that point the machine won't start anymore. (can't find boot device)

Thanks for reading,


Ing. Roland Gsell
(Systems Engineer)


Siedl Networks GmbH

A-3500 Krems an der Donau, Wiener Straße 74, Austria
Tel: +43 2732 71545 - 16 | Mobil: +43 676 840 633 516 | Fax: +43 2732 71545 - 99
E-Mail: <mailto:roland.klein at siedl.net>   roland.gsell at siedl.net <mailto:roland.gsell at siedl.net> | www.siedl.net <http://www.siedl.net/> 

IT Infrastruktur & Systembetreuung | E-Mail & Groupware | High Availability & Monitoring
UID: ATU62117818, Handelsgericht Krems an der Donau, Firmenbuchnummer FN270789w

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.linbit.com/pipermail/drbd-user/attachments/20150317/08ea1a23/attachment.htm>

More information about the drbd-user mailing list