Re: [ovirt-users] moving storage away from a single point of failure

I thought I had read where Gluster had corrected this behavior. That's disappointing. On Tue, Sep 22, 2015 at 4:18 AM Alastair Neil <ajneil.tech(a)gmail.com&gt; wrote: > My own experience with gluster for VMs is that it is just fine until you > need to bring down a node and need the VM's to be live. I have a replica 3 > gluster server and, while the VMs are fine while the node is down, when it > is brought back up, gluster attempts to heal the files on the downed node > and the ensuing i/o freezes the VM's until the heal is complete, and with > many VM's on a storage volume that can take hours. I have migrated all my > critical VMs back onto NFS. There are changes coming soon in gluster that > will hopefully mitigate this (better granualarity in the data heals, i/o > throttling during heals etc.) but for now I am keeping most of my VMs on > nfs. > > The alternative is to set the quorum so that the VM volume goes read only > when a node goes down. This may seem mad, but at least your VMs are frozen > only while a node is down and not for hours afterwards. > > > > On 22 September 2015 at 05:32, Daniel Helgenberger < > daniel.helgenberger(a)m-box.de&gt; wrote: > >> >> >> On 18.09.2015 23:04, Robert Story wrote: >> > Hi, >> >> Hello Robert, >> >> > >> > I'm running oVirt 3.5 in our lab, and currently I'm using NFS to a >> single >> > server. I'd like to move away from having a single point of failure. >> >> In this case have a look at iSCSI or FC storage. If you have redundant >> contollers and switches >> the setup should be reliable enough? >> >> > Watching the mailing list, all the issues with gluster getting out of >> sync >> > and replica issues has me nervous about gluster, plus I just have 2 >> > machines with lots of drive bays for storage. >> >> Still, I would stick to gluster if you want a replicated storage: >> - It is supported out of the box and you get active support from lots >> of users here >> - Replica3 will solve most out of sync cases >> - I dare say other replicated storage backends do suffer from the same >> issues, this is by design. >> >> Two things you should keep in mind when running gluster in production: >> - Do not run compute and storage on the same hosts >> - Do not (yet) use Gluster as storage for Hosted Engine >> >> > I've been reading about GFS2 >> > and DRBD, and wanted opinions on if either is a good/bad idea, or to >> see if >> > there are other alternatives. >> > >> > My oVirt setup is currently 5 nodes and about 25 VMs, might double in >> size >> > eventually, but probably won't get much bigger than that. >> >> In the end, it is quite easy to migrate storage domains. If you are >> satisfied with your lab >> setup, put it in production and add storage later and move the disks. >> Afterwards, remove old >> storage domains. >> >> My to cent with gluster: It runs quite stable since some time now if you >> do not touch it. >> I never had issues when adding bricks, though removing and replacing >> them can be very tricky. >> >> HTH, >> >> > >> > >> > Thanks, >> > >> > Robert >> > >> >> -- >> Daniel Helgenberger >> m box bewegtbild GmbH >> >> P: +49/30/2408781-22 >> F: +49/30/2408781-10 >> >> ACKERSTR. 19 >> D-10115 BERLIN >> >> >> www.m-box.de www.monkeymen.tv >> >> Geschäftsführer: Martin Retschitzegger / Michaela Göllner >> Handeslregister: Amtsgericht Charlottenburg / HRB 112767 >> _______________________________________________ >> Users mailing list >> Users(a)ovirt.org >> http://lists.ovirt.org/mailman/listinfo/users >> > > _______________________________________________ > Users mailing list > Users(a)ovirt.org > http://lists.ovirt.org/mailman/listinfo/users > -- *Michael Kleinpaste* Senior Systems Administrator SharperLending, LLC. www.SharperLending.com Michael.Kleinpaste(a)SharperLending.com (509) 324-1230 Fax: (509) 324-1234 _______________________________________________ Users mailing list Users(a)ovirt.org http://lists.ovirt.org/mailman/listinfo/users