On Thu, Nov 21, 2019 at 9:56 AM Jason Dillaman <[email protected]> wrote: > > On Thu, Nov 21, 2019 at 8:49 AM Vikas Rana <[email protected]> wrote: > > > > Thanks Jason for such a quick response. We are on 12.2.10. > > > > Checksuming a 200TB image will take a long time. > > How would mounting an RBD image and scanning the image be faster? Are > you only using a small percentage of the image?
... and of course, you can mount an RBD snapshot in read-only mode. > > To test the DR copy by mounting it, these are the steps I'm planning to > > follow > > 1. Demote the Prod copy and promote the DR copy > > 2. Do we have to recreate the rbd mirror relationship going from DR to > > primary? > > 3. Mount and validate the data > > 4. Demote the DR copy and promote the Prod copy > > 5. Revert the peer relationship if required? > > > > Did I do it right or miss anything? > > You cannot change the peers or you will lose the relationship. If you > insist on your course of action, you just need to be configured for > two-way mirroring and leave it that way. > > > > > Thanks, > > -Vikas > > > > -----Original Message----- > > From: Jason Dillaman <[email protected]> > > Sent: Thursday, November 21, 2019 8:33 AM > > To: Vikas Rana <[email protected]> > > Cc: ceph-users <[email protected]> > > Subject: Re: [ceph-users] RBD Mirror DR Testing > > > > On Thu, Nov 21, 2019 at 8:29 AM Vikas Rana <[email protected]> wrote: > > > > > > Hi all, > > > > > > > > > > > > We have a 200TB RBD image which we are replicating using RBD mirroring. > > > > > > We want to test the DR copy and make sure that we have a consistent copy > > > in case primary site is lost. > > > > > > > > > > > > We did it previously and promoted the DR copy which broken the DR copy > > > from primary and we have to resync the whole 200TB data. > > > > > > > > > > > > Is there any correct way of doing it so we don’t have to resync all 200TB > > > again? > > > > Yes, create a snapshot on the primary site and let it propagate to the > > non-primary site. Then you can compare checksums at the snapshot w/o having > > to worry about the data changing. Once you have finished, delete the > > snapshot on the primary site and it will propagate over to the non-primary > > site. > > > > > > > > > > > Can we demote current primary and then promote the DR copy and test and > > > then revert back? Will that require the complete 200TB sync? > > > > > > > It's only the forced-promotion that causes split-brain. If you gracefully > > demote from site A and promote site B, and then demote site B and promote > > site A, that will not require a sync. However, again, it's probably just > > easier to use a snapshot. > > > > > > > > Thanks in advance for your help and suggestions. > > > > > > > > > > > > Thanks, > > > > > > -Vikas > > > > > > _______________________________________________ > > > ceph-users mailing list > > > [email protected] > > > http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com > > > > > > > > -- > > Jason > > > > > > > -- > Jason -- Jason _______________________________________________ ceph-users mailing list [email protected] http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
