So today I've been asked to configure a cluster on Centos7 using pacemaker and drbd.
Everything was going fine until I tried to create a the local meta data for my resource ( a simple web server).
The output of my
drbdadm create-md wwwdata
command left me a bit puzzled.
open(/dev/centos_rick/drbd-demo) failed: Device or resource busy
being me I tried to force through with:
Exclusive open failed. Do it anyways? [need to type 'yes' to confirm]
And just ended up with an error:
Command 'drbdmeta 1 v08 /dev/centos_rick/drbd-demo internal create-md'
terminated with exit code 20
Does anyone have an idea of why i'm confronted to this.
DRBD configuration:
resource wwwdata {
protocol C;
meta-disk internal;
device /dev/drbd1;
syncer {
verify-alg sha1;
}
net {
allow-two-primaries;
}
on rick {
disk /dev/centos_rick/drbd-demo;
address 192.168.1.60:7789;
}
on summer {
disk /dev/centos_summer/drbd-demo;
address 192.168.1.61:7789;
}
}
Best Answer
Something is holding the backing disk open preventing DRBD from being able to create the meta-data on it. Make sure the device isn't mounted, then try recreating your metadata:
# umount /dev/centos_rick/drbd-demo && drbdadm create-md wwwdata