I did promote the non-primary image, or I couldn't disable the image mirror. Jason Dillaman <jdillama@xxxxxxxxxx> 于2020年6月9日周二 下午7:19写道： > On Mon, Jun 8, 2020 at 11:42 PM Zhenshi Zhou <deaderzzs@xxxxxxxxx> wrote: > > > > I have just done a test on rbd-mirror. Follow the steps: > > 1. deploy two new clusters, clusterA and clusterB > > 2. configure one-way replication from clusterA to clusterB with > rbd-mirror > > 3. write data to rbd_blk on clusterA once every 5 seconds > > 4. get information with 'rbd mirror image status rbd_blk', the "state" > is "up+replaying" > > 5. demote image on clusterA(just wanna stop syncing and switch client > connection to clusterB) > > > > The result is: > > 1. I find that the "last_update" from "rbd mirror image status" updates > every 30 seconds, which means I will lose at most 30s of data > > The status updates are throttled but not the data transfer. > > > 2. I stopped syncing on 11:02, while the data from rbd_blk on the > clusterB is not newer than 10:50. > > After demotion, you need to promote on the original non-primary side > (w/o the --force) option. It won't let you non-force promote unless it > has all the data copied. It will continue to copy data while the other > side has been demoted until it fully catches up. > > > > > Did I have the wrong steps in the switching progress? > > > > > > > > Zhenshi Zhou <deaderzzs@xxxxxxxxx> 于2020年6月9日周二 上午8:57写道： > >> > >> Well, I'm afraid that the image didn't replay continuously, which means > I have some data lost. > >> The "rbd mirror image status" shows the image is replayed and its time > is just before I demote > >> the primary image. I lost about 24 hours' data and I'm not sure whether > there is an interval > >> between the synchronization. > >> > >> I use version 14.2.9 and I deployed a one direction mirror. > >> > >> Zhenshi Zhou <deaderzzs@xxxxxxxxx> 于2020年6月5日周五 上午10:22写道： > >>> > >>> Thank you for the clarification. That's very clear. > >>> > >>> Jason Dillaman <jdillama@xxxxxxxxxx> 于2020年6月5日周五 上午12:46写道： > >>>> > >>>> On Thu, Jun 4, 2020 at 3:43 AM Zhenshi Zhou <deaderzzs@xxxxxxxxx> > wrote: > >>>> > > >>>> > My condition is that the primary image being used while rbd-mirror > sync. > >>>> > I want to get the period between the two times of rbd-mirror > transfer the > >>>> > increased data. > >>>> > I will search those options you provided, thanks a lot :) > >>>> > >>>> When using the original (pre-Octopus) journal-based mirroring, once > >>>> the initial sync completes to transfer the bulk of the image data from > >>>> a point-in-time dynamic snapshot, any changes post sync will be > >>>> replayed continuously from the stream of events written to the journal > >>>> on the primary image. The "rbd mirror image status" against the > >>>> non-primary image will provide more details about the current state of > >>>> the journal replay. > >>>> > >>>> With the Octopus release, we now also support snapshot-based mirroring > >>>> where we transfer any image deltas between two mirroring snapshots. > >>>> These mirroring snapshots are different from user-created snapshots > >>>> and their life-time is managed by RBD mirroring (i.e. they are > >>>> automatically pruned when no longer needed). This version of mirroring > >>>> probably more closely relates to your line of questioning since the > >>>> period of replication is at whatever period you create new mirroring > >>>> snapshots (provided your two clusters can keep up). > >>>> > >>>> > > >>>> > Eugen Block <eblock@xxxxxx> 于2020年6月4日周四 下午3:28写道： > >>>> > > >>>> > > The initial sync is a full image sync, the rest is based on the > object > >>>> > > sets created. There are several options to control the mirroring, > for > >>>> > > example: > >>>> > > > >>>> > > rbd_journal_max_concurrent_object_sets > >>>> > > rbd_mirror_concurrent_image_syncs > >>>> > > rbd_mirror_leader_max_missed_heartbeats > >>>> > > > >>>> > > and many more. I'm not sure I fully understand what you're asking, > >>>> > > maybe you could rephrase your question? > >>>> > > > >>>> > > > >>>> > > Zitat von Zhenshi Zhou <deaderzzs@xxxxxxxxx>: > >>>> > > > >>>> > > > Hi Eugen, > >>>> > > > > >>>> > > > Thanks for the reply. If rbd-mirror constantly synchronize > changes, > >>>> > > > what frequency to replay once? I don't find any options I can > config. > >>>> > > > > >>>> > > > Eugen Block <eblock@xxxxxx> 于2020年6月4日周四 下午2:54写道： > >>>> > > > > >>>> > > >> Hi, > >>>> > > >> > >>>> > > >> that's the point of rbd-mirror, to constantly replay changes > from the > >>>> > > >> primary image to the remote image (if the rbd journal feature > is > >>>> > > >> enabled). > >>>> > > >> > >>>> > > >> > >>>> > > >> Zitat von Zhenshi Zhou <deaderzzs@xxxxxxxxx>: > >>>> > > >> > >>>> > > >> > Hi all, > >>>> > > >> > > >>>> > > >> > I'm gonna deploy a rbd-mirror in order to sync image from > clusterA to > >>>> > > >> > clusterB. > >>>> > > >> > The image will be used while syncing. I'm not sure if the > rbd-mirror > >>>> > > will > >>>> > > >> > sync image > >>>> > > >> > continuously or not. If not, I will inform clients not to > write data > >>>> > > in > >>>> > > >> it. > >>>> > > >> > > >>>> > > >> > Thanks. Regards > >>>> > > >> > _______________________________________________ > >>>> > > >> > ceph-users mailing list -- ceph-users@xxxxxxx > >>>> > > >> > To unsubscribe send an email to ceph-users-leave@xxxxxxx > >>>> > > >> > >>>> > > >> > >>>> > > >> _______________________________________________ > >>>> > > >> ceph-users mailing list -- ceph-users@xxxxxxx > >>>> > > >> To unsubscribe send an email to ceph-users-leave@xxxxxxx > >>>> > > >> > >>>> > > > >>>> > > > >>>> > > > >>>> > > > >>>> > _______________________________________________ > >>>> > ceph-users mailing list -- ceph-users@xxxxxxx > >>>> > To unsubscribe send an email to ceph-users-leave@xxxxxxx > >>>> > >>>> > >>>> > >>>> -- > >>>> Jason > >>>> > > > -- > Jason > > _______________________________________________ ceph-users mailing list -- ceph-users@xxxxxxx To unsubscribe send an email to ceph-users-leave@xxxxxxx
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