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Zingaro2002
8th May 2008, 13:08
Hi,
I'm following
Virtual Machine Replication & Failover with VMWare Server & Debian Etch (4.0) howto.
I have not yet completed it, but I have to say that it's wonderful!
Thanks to Francis Theys, Falko Timme, Till Brehm!!!

Now my question...
I am arrived at the point in which I write
mount -t ext3 /dev/drbd0 /var/vm
on both servers.

On server1 the command executes correctly.

On server2 it says:
mount: block device /dev/drbd0 is write-protected, mounting read-only
mount: /dev/drbd0 already mounted or /var/vm busy

And of course if I put a "df -h" command I have:
On server1:
Filesystem Dimens. Used Avail. Usage% Mounted on
/dev/hda2 7,0G 1,2G 5,5G 18% /
tmpfs 475M 0 475M 0% /lib/init/rw
udev 10M 56K 10M 1% /dev
tmpfs 475M 0 475M 0% /dev/shm
/dev/hda1 464M 17M 423M 4% /boot
/dev/drbd0 450G 199M 427G 1% /var/vm

and on server2
Filesystem Dimens. Used Avail. Usage% Mounted on
/dev/hda2 7,0G 1,2G 5,6G 17% /
tmpfs 475M 0 475M 0% /lib/init/rw
udev 10M 56K 10M 1% /dev
tmpfs 475M 0 475M 0% /dev/shm
/dev/hda1 464M 15M 425M 4% /boot

Is it right?

***************

Another question.
If I write "cat /proc/drbd" I have:

On server 1:
version: 0.7.21 (api:79/proto:74)
SVN Revision: 2326 build by root@server1, 2008-05-08 11:30:30
0: cs:Connected st:Primary/Secondary ld:Consistent
ns:24 nr:0 dw:7641924 dr:273 al:7259 bm:0 lo:0 pe:0 ua:0 ap:0
1: cs:Unconfigured

On server 2:
version: 0.7.21 (api:79/proto:74)
SVN Revision: 2326 build by root@server2, 2008-05-08 11:30:31
0: cs:Connected st:Secondary/Primary ld:Consistent
ns:0 nr:24 dw:7641924 dr:0 al:0 bm:0 lo:0 pe:0 ua:0 ap:0
1: cs:Unconfigured

Is it right?

If I create a simple text file on /var/vm in server1 I would expect to find it also on server 2 but... nothing!
Am I missing something?

I'd like to have clearer ideas before going further with this very useful howto.

Thanks to the authors (I hope some of them can help me!!!)


Can anyone help me?

thanis
11th May 2008, 12:37
Hi, this is "normal" as you can't mount the DRBD volume on both servers at once. You should mount it on one server, and then use it for the VM creation. DRBD will replicate is.

If you "unmount" the DRBD volume and then put the primary server "offline", you will be able to mount the DRBD volume on your second server.

Kind regards,
Thanis

PS: I should be more active here, it has been ages since my last visit :p

Zingaro2002
12th May 2008, 11:08
Thank you very much...

and what about my second question? (see above)

thanis
13th May 2008, 16:14
As for question 2: YEs, that is a correct output :) It says your DRBD volume is replicated and consistent .