Ashish Pandey
2017-Mar-16 11:17 UTC
[Gluster-users] [Gluster-devel] Proposal to deprecate replace-brick for "distribute only" volumes
----- Original Message ----- From: "Atin Mukherjee" <atin.mukherjee83 at gmail.com> To: "Raghavendra Talur" <rtalur at redhat.com>, gluster-devel at gluster.org, gluster-users at gluster.org Sent: Thursday, March 16, 2017 4:22:41 PM Subject: Re: [Gluster-devel] [Gluster-users] Proposal to deprecate replace-brick for "distribute only" volumes Makes sense. On Thu, 16 Mar 2017 at 06:51, Raghavendra Talur < rtalur at redhat.com > wrote: Hi, In the last few releases, we have changed replace-brick command such that it can be called only with "commit force" option. When invoked, this is what happens to the volume: a. distribute only volume: the given brick is replaced with a empty brick with 100% probability of data loss. b. distribute-replicate: the given brick is replaced with a empty brick and self heal is triggered. If admin is wise enough to monitor self heal status before another replace-brick command, data is safe. c. distribute-disperse: same as above in distribute-replicate My proposal is to fully deprecate replace-brick command for "distribute only" volumes. It should print out a error "The right way to replace brick for distribute only volume is to add brick, wait for rebalance to complete and remove brick" and return a "-1". It makes sense. I just don't see any use of add-brick before remove-brick except the fact that it will help to keep the overall storage capacity of volume intact . What is the guarantee that the files on the brick which we want to replace would migrate to added brick? If a brick, which we want to replace, is healthy and we just want to replace it then perhaps we should provide a command to copy those files to new brick and then remove the old brick. <blockquote> Thoughts? Thanks, Raghavendra Talur _______________________________________________ Gluster-users mailing list Gluster-users at gluster.org http://lists.gluster.org/mailman/listinfo/gluster-users </blockquote> -- --Atin _______________________________________________ Gluster-devel mailing list Gluster-devel at gluster.org http://lists.gluster.org/mailman/listinfo/gluster-devel -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.gluster.org/pipermail/gluster-users/attachments/20170316/bb770cdc/attachment.html>
Joe Julian
2017-Mar-16 12:59 UTC
[Gluster-users] [Gluster-devel] Proposal to deprecate replace-brick for "distribute only" volumes
On March 16, 2017 4:17:04 AM PDT, Ashish Pandey <aspandey at redhat.com> wrote:> > >----- Original Message ----- > >From: "Atin Mukherjee" <atin.mukherjee83 at gmail.com> >To: "Raghavendra Talur" <rtalur at redhat.com>, gluster-devel at gluster.org, >gluster-users at gluster.org >Sent: Thursday, March 16, 2017 4:22:41 PM >Subject: Re: [Gluster-devel] [Gluster-users] Proposal to deprecate >replace-brick for "distribute only" volumes > >Makes sense. > >On Thu, 16 Mar 2017 at 06:51, Raghavendra Talur < rtalur at redhat.com > >wrote: > > >Hi, > >In the last few releases, we have changed replace-brick command such >that it can be called only with "commit force" option. When invoked, >this is what happens to the volume: > >a. distribute only volume: the given brick is replaced with a empty >brick with 100% probability of data loss. >b. distribute-replicate: the given brick is replaced with a empty >brick and self heal is triggered. If admin is wise enough to monitor >self heal status before another replace-brick command, data is safe. >c. distribute-disperse: same as above in distribute-replicate > >My proposal is to fully deprecate replace-brick command for >"distribute only" volumes. It should print out a error "The right way >to replace brick for distribute only volume is to add brick, wait for >rebalance to complete and remove brick" and return a "-1". > > > > >It makes sense. >I just don't see any use of add-brick before remove-brick except the >fact that it will >help to keep the overall storage capacity of volume intact . >What is the guarantee that the files on the brick which we want to >replace >would migrate to added brick? > >If a brick, which we want to replace, is healthy and we just want to >replace it then perhaps we should provide >a command to copy those files to new brick and then remove the old >brick.We used to have a command that did just that. It was replace-brick.> > > ><blockquote> >Thoughts? > >Thanks, >Raghavendra Talur >_______________________________________________ >Gluster-users mailing list >Gluster-users at gluster.org >http://lists.gluster.org/mailman/listinfo/gluster-users > ></blockquote>-- Sent from my Android device with K-9 Mail. Please excuse my brevity.