Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.
----- Original Message ----- > From: "Digimer" <linux at alteeve.com> > To: drbd-user at lists.linbit.com > Sent: Thursday, December 1, 2011 2:18:42 PM > Subject: Re: [DRBD-user] Cluster filesystem question > > On 12/01/2011 02:13 PM, Lars Ellenberg wrote: > > On Thu, Dec 01, 2011 at 01:58:15PM -0500, Kushnir, Michael > > (NIH/NLM/LHC) [C] wrote: > >> Hi Lars, > >> > >> I'm a bit confused by this discussion. Can you please clarify the > >> difference? > >> > >> What I think you are saying is: > >> > >> OK: > >> Dual-primary DRBD -> cluster aware something (OCFS, GFS, clvmd, > >> etc...) -> exported via iSCSI on both nodes -> multipathed on the > >> client > > > > No. > > > > OK: > > Dual-primary DRBD (done right) -> cluster aware something (OCFS, > > GFS, clvmd, etc...) > > > > NOT OK: > > -> exported via iSCSI on both nodes -> multipathed on the client > > > > NOT OK: > > anything non-cluster-aware using it "concurrently" on both nodes. > > What I've done in the past, and perhaps it isn't the wisest (Lars, > Florian?), is to create a Dual-primary DRBD (with fencing!), then > export > it as-is to my nodes using a floating/virtual IP address managed by a > simple cluster. > > Then on the clients (all of whom are in the same cluster), I mount > the > iSCSI target and set it up as a clustered LVM PV/VG/LVs. If you need > a > normal FS, then format one or more of the LVs using a cluster-aware > FS. > > When the primary node (the one with the floating IP) fails, all the > cluster has to do is move the IP down to the backup node and it's > ready > to go. I suppose you could just as easily do Primary/Secondary and > include the promotion of the backup to primary as part of the > failover, > too. In my case, knowing I had fencing in place already, I went for > the > "simpler" cluster config of managing an IP only. > I could be totally wrong but from what I read above you're not multipathing on your clients; just speeding up failover times; so (IMHO) you fit the "OK". But I'm sure one of the experts will weigh in. :-) Jake > Caveat - I did not read the thread before now. If this is totally out > to > left field, my apologies. :) > > -- > Digimer > E-Mail: digimer at alteeve.com > Freenode handle: digimer > Papers and Projects: http://alteeve.com > Node Assassin: http://nodeassassin.org > "omg my singularity battery is dead again. > stupid hawking radiation." - epitron > _______________________________________________ > drbd-user mailing list > drbd-user at lists.linbit.com > http://lists.linbit.com/mailman/listinfo/drbd-user > >