[DRBD-user] [Q] Shrinking the drbd [Was How do I use drbdsetup resize with LVM and no secondary?]

[Maurice Volaski]

At 12:00 PM +0200 6/18/05, drbd-user-request at linbit.com wrote:
>/ 2005-06-15 10:40:53 -0400
>\ Maurice Volaski:
>>  I have drbd running atop LVM on a primary box. The secondary hardware
>>  does not exist yet. Can I still resize in this situation or would
>>  drbdsetup complain there is no corresponding hardware to talk to?
>
>To be honest, I'm not exactly sure...
>If it _never_ saw a peer yet, it should work.

I shall soon find out.

>  > Second, will drbd be able to figure out how big the LVM is and just
>  > resize on the command "drbd resize" or do I need to specify it and if
>>  so, do I just use the size given by lvdisplay exactly as it is given?
>>  I am assuming drbd takes some tiny amount off for its metadata.
>
>it typically should figure by itself.

It does. :)

But now I have to shrink one. That's more complicated. The question 
is whether drbd resize will know to use the filesystem's size, which 
is correct, or the lvm size, which, since it hasn't been reduced yet, 
is wrong? If it picks the wrong one, should I give it the 
filesystem's exact size (fdisk -s device)?
-- 

Maurice Volaski, mvolaski at aecom.yu.edu
Computing Support, Rose F. Kennedy Center
Albert Einstein College of Medicine of Yeshiva University