[CentOS] Unable to use DRBD after a reboot

Sat Mar 14 08:42:05 UTC 2009
Fabian Arrotin <fabian.arrotin at arrfab.net>

robert mena wrote:
> Hi,
> 
> I have two servers in a drbd primary/secondary setup.   Everything was 
> fine until I had to reboot both servers.
> 
> The primary rebooted first, the secondary assumed fine, but when the 
> (old primary) server got back online it was unable to mount the drbd fs 
> complaining about the modules.
> 
> I've tried to find out the problem but the servers seem to have the same 
> setup
> 
> rpm -qa | grep drbd
> drbd82-8.2.6-1.el5.centos
> kmod-drbd82-8.2.6-2
> 
> Kernel 2.6.18-92.1.22.el5 #1 SMP
> 
> Am I missing something?
> 
> thanks.
> 

Is the drbd module loaded on the failing node ?
kmod-drbd82-8.2.6-2 contains the drbd.ko module (in 
/lib/modules/2.6.18-92.1.13.el5/extra/drbd82/drbd.ko)
When you update your kernel, a /sbin/weak-modules script is called to 
symlink the extras kmods from previous kernels to all install kernels. 
So that means that in your actual 
/lib/modules/2.6.18-92.1.22.el5/weak-updates/drbd82/ folder contains 
symlinks to the original one.
It that the case ? have you manually deleted the old 
/lib/modules/2.6.18-92.1.13.el5/ directory ?

-- 
--
Fabian Arrotin
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