TOPIC:

Hi Guys

Is it possible to configure a stacked-on-top-of configuration in DRBD with HA-Lizard for Backup?

Thanks n'Cheers!

We haven't tried that, but it should be transparent to what ha-lizard/iscsi-ha are doing.
Just make sure not to pass the stacked DRBD resource name to the iscsi-ha config.

cat /etc/drbd.conf
# You can find an example in /usr/share/doc/drbd.../drbd.conf.example

include "drbd.d/global_common.conf";
include "drbd.d/*.res";

#global { usage-count no; }
#common { syncer { rate 100M; } }
resource iscsi1 {
protocol C;
net {
after-sb-0pri discard-zero-changes;
after-sb-1pri consensus; cram-hmac-alg sha1;
shared-secret PUTyourSECREThere;
}
on xeho1 {
device /dev/drbd1;
disk /dev/sdb;
address 10.10.10.1:7789;
meta-disk internal;
}
on xeho2 {
device /dev/drbd1;
disk /dev/sdb;
address 10.10.10.2:7789;
meta-disk internal;
}
}
resource iscsi2 {
protocol C;
net {
after-sb-0pri discard-zero-changes;
after-sb-1pri consensus; cram-hmac-alg sha1;
shared-secret PUTyourSECREThere;
}
on xeho1 {
device /dev/drbd2;
disk /dev/sdc;
address 10.10.10.1:7790;
meta-disk internal;
}
on xeho2 {
device /dev/drbd2;
disk /dev/sdc;
address 10.10.10.2:7790;
meta-disk internal;
}
}

resource rep {
net {
protocol A;
}

stacked-on-top-of iscsi1 {
device /dev/drbd10;
address 10.10.10.3:7789;
}

on xerp1 {
device /dev/drbd10;
disk /dev/sdb1;
address 10.10.10.4:7789; # Public IP of the backup node
meta-disk internal;
}
}

Hmm im not sure whats exactly the problem. May you can help on this.


drbdadm create-md --stacked rep
Writing meta data...
pvs stderr: /dev/drbd1: Skipping (regex)
pvs stderr: Failed to read physical volume "/dev/drbd1"
pvs stderr: Unlocking /var/lock/lvm/P_global
pvs stderr: _undo_flock /var/lock/lvm/P_global

md_offset 107370864640
al_offset 107370831872
bm_offset 107367555072

Found LVM2 physical volume signature
104851128 kB left usable by current configuration
Could not determine the size of the actually used data area.

Device size would be truncated, which
would corrupt data and result in
'access beyond end of device' errors.
If you want me to do this, you need to zero out the first part
of the device (destroy the content).
You should be very sure that you mean it.
Operation refused.

Command 'drbdmeta 10 v08 /dev/drbd1 internal create-md' terminated with exit code 40

i ran this from the master

ok i got this. it was because there was already some sort of LVM creates from xen that prevented drbd from creating the stacked ressource. You can use existing LVM but there is some work to be done or just delete the SR from XEN.

Now my 3rd Node says connected but ds is inconsistent

10: cs:Connected ro:Secondary/Secondary ds:Inconsistent/Inconsistent A r

---

ns:0 nr:0 dw:0 dr:0 al:0 bm:0 lo:0 pe:0 ua:0 ap:0 ep:1 wo:f oos:104851128

They did not knew which was the up2date version.

on the 3rd node:

drbdadm invalidate rep