[DRBD-user] Best way to change a backend-device to a other device

[Stefan Mühlbacher - Freisei XP8]

Hi!

Config:

(r2)

  on server1 {
     device     /dev/drbd2;
     disk       /dev/md0;
     address    192.168.2.1:7790;
     meta-disk  internal;
   }

   on server2 {
     device    /dev/drbd2;
     disk      /dev/md0;
     address   192.168.2.2:7790;
     meta-disk internal;
   }


New-Config should be

(r2)

  on server1 {
     device     /dev/drbd2;
     disk       /dev/sdc;
     address    192.168.2.1:7790;
     meta-disk  internal;
   }

   on server2 {
     device    /dev/drbd2;
     disk      /dev/sdc;
     address   192.168.2.2:7790;
     meta-disk internal;
   }

state:
server2:~# cat /proc/drbd
version: 0.7.23 (api:79/proto:74)
SVN Revision: 2686 build by root at server2, 2007-02-05 13:12:50
  0: cs:Connected st:Secondary/Primary ld:Consistent
     ns:0 nr:844998180 dw:844998180 dr:0 al:0 bm:2734 lo:0 pe:0 ua:0 ap:0
  1: cs:Unconfigured
  2: cs:Connected st:Secondary/Primary ld:Consistent
     ns:0 nr:1168517772 dw:1168517772 dr:0 al:0 bm:2091 lo:0 pe:0 ua:0 ap:0
  3: cs:Connected st:Primary/Secondary ld:Consistent
     ns:1319070548 nr:2331532 dw:1321968412 dr:164825497 al:212280 
bm:498 lo:0 pe:0 ua:0 ap:0
  4: cs:Connected st:Primary/Secondary ld:Consistent
     ns:1340056080 nr:0 dw:1340640164 dr:121175741 al:458223 bm:455 lo:0 
pe:8 ua:0 ap:7





So, on each server i?ve 2 250GB SATA-HDDs in a Raid0. I want to Replace 
this devices with ONE 500 GB SATA-HDD in each Server.

I want to do this with as less as possible offtime. I think it should 
possible to get it with to Failovers.
Now i?ve no Idea how or at which moment i can change the /etc/drbd.conf 
to the new devices. (i think, both-config-files must be identical every 
time??)

Or is it possible to set a softlink from /dev/md0 to /dev/sdc?

Thanks for Help -

Sincerly Freisei