[DRBD-user] Newbie

bart.coninckx at telenet.be bart.coninckx at telenet.be
Thu Feb 10 09:16:47 CET 2011

Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.


Chris,

DRBD works on top of a block device (partition, LVM, harddisk) and replicates "low-level" what ever is on top of the DRBD device. In your case this will probably a ext3 filesystem with /home mounted on it. 

Hardware does not need to be identical, but when using protocol C (safest, write OK only if confirmed by other node) replication or syncing speed will be limited to the slowest of the two servers.

About the underlaying device: I usually use LVM since it allows me to easily resize the DRBD device on top of it (in case the DRBD metadata is on the same device). 


HTH,

Bart



----- "Chris Barnes" <chris-barnes at tamu.edu> schreef:

> First, I hope this is ok to post this question in this email list...
> Secondly, I have been reading the Users Guide at 
> http://www.drbd.org/users-guide/ - but still have a few "before I
> start" 
> type of questions.
> 
> I am wanting to create a high-availability cluster and I *think* DRBD
> is 
> what I am looking for.   But I'm not quite sure.
> 
> 
> My *thought* was to use DRBD to mirror the /home filesystem between
> the 
> 2 machines - but I have someone working for me that is saying the DRBD
> 
> mirrors "entire systems".   If he is correct, wouldn't that mean that
> 2 
> computers would require the exact same hardware?
> 
> 
> Or am I not even thinking of DRBD in the correct terms?  After all, a
> 
> "true high availability cluster" would mean my down time is measured
> in 
> seconds, right?   I would not have that if all I am mirroring is
> /home...
> 
> 
> 
> My systems (if it matters):
> I have one disk array (10TB, Raid5+1) with /home on it's own
> filesystem 
> using 7.2T (according to the df command).  This machine is in
> production 
> and has been in use for a couple of years now.
> 
> I have another system that is completely blank and ready to configure
> 
> any way that makes sense.  It has 2 250gb drives in a hardware Raid0,
> 
> and 8 2tb drives in a hardware Raid5 (currently Raid5+3 - trying to
> give 
> me 8tb of space).
> 
> 
> 
> So - where do I start?
> By that I mean - I am unsure of even how to partition the drives on
> the 
> new system:  do I use LVM, or attempt to use partitions similar to the
> 
> old system?  Does it matter?
> 
> 
> -- 
> Chris Barnes                           AOL IM: CNBarnes
> chris-barnes at tamu.edu                Yahoo IM: chrisnbarnes
> Computer Systems Manager               MSN IM: chris at txbarnes.com
> Department of Physics                      ph: 979-845-1379
> Texas A&M University                      fax: 979-845-2590
> _______________________________________________
> drbd-user mailing list
> drbd-user at lists.linbit.com
> http://lists.linbit.com/mailman/listinfo/drbd-user



More information about the drbd-user mailing list