On our 3Par SAN we use O2CB_HEARTBEAT_THRESHOLD of 76 (180 seconds). This is the time needed for the controller to fully recover in case of a crash or software upgrade. Multipath is configured with a polling_interval of 10, no_path_retry of 60. With these settings we are able to survive SAN switch crash (has happened), SAN controller crash (has happened) and SAN controller upgrades.
> -----Original Message----- > From: ocfs2-users-boun...@oss.oracle.com [mailto:ocfs2-users- > boun...@oss.oracle.com] On Behalf Of Elliott Perrin > Sent: Thursday, March 18, 2010 6:58 PM > To: ocfs2-users@oss.oracle.com > Subject: Re: [Ocfs2-users] OCFS2 Multipath Configuration > > I have seen node fences occur on all of our OCFS2 systems when the > O2CB_HEARTBEAT_THRESHOLD is set less than 31 on both FC and iSCSI > connected systems. In some testing I have done I found that all nodes > would panic with O2CB_HEARTBEAT_THRESHOLD set to any value less than 15 > and we would see single node fencing with values between 15 and 30. > With the O2CB_HEARTBEAT_THRESHOLD set to 31 or greater we do not see a > fence occur when fabric disruption occurs, again on both iSCSI and FC. > > This is with a multipath configuration that includes > > polling_interval "5" > no_path_retry "5" > features "1 queue_if_no_path" > failback "immediate" > selector "round-robin 0" > > as some of the configuration variables used in the setup. > > As long as the output of mount (not mounted.ocfs2) shows that your file > system mount is from a /dev/mapper created multipath device then OCFS2 > is using the multipath provided device. > > > > -----Original Message----- > > From: ocfs2-users-boun...@oss.oracle.com [mailto:ocfs2-users- > > boun...@oss.oracle.com] On Behalf Of Sunil Mushran > > Sent: Thursday, March 18, 2010 2:11 PM > > To: David Johle > > Cc: ocfs2-users@oss.oracle.com > > Subject: Re: [Ocfs2-users] OCFS2 Multipath Configuration > > > > Yeah.. mounted is a bit dumb. In the next release, it will recognize > > /dev/mapper devices. We still need to teach it to handle multipathing > > fully. > > > > David Johle wrote: > > > I'm not sure about why mounted.ocfs2 is showing both the dm and the > > > sd devices for the same volume. But this could all be very similar > > > to a problem I've experienced with OCFS2 & mount finding the right > > > device with multipathing. > > > > > > See the following thread for some more insight: > > > http://oss.oracle.com/pipermail/ocfs2-users/2009-March/003391.html > > > > > > > > > > > > At 04:12 PM 3/15/2010, you wrote: > > > > > >> Date: Wed, 16 Dec 2009 14:20:45 -0500 > > >> From: "Nyburg, Daryl" <daryl.nyb...@utoledo.edu> > > >> Subject: [Ocfs2-users] OCFS2 Multipath Configuration > > >> To: <ocfs2-users@oss.oracle.com> > > >> > > >> Hello All, > > >> I am having some problems configuring OCFS2 to use only the > > >> multipath device name. We have been doing failover testing with > our > > >> ISCI SAN and as soon as we unplug one NIC the following messages > > appear > > >> in /var/log/messages and the system reboots. > > >> > > >> > > >> Dec 16 12:39:03 mcprac01 kernel: (56,6):o2hb_write_timeout:172 > > ERROR: > > >> Heartbeat write timeout to device dm-34 after 120000 milliseconds > > >> Dec 16 12:39:03 mcprac01 kernel: (56,6):o2hb_stop_all_regions:1967 > > >> ERROR: stopping heartbeat on all active regions. > > >> Dec 16 12:39:03 mcprac01 kernel: ocfs2 is very sorry to be fencing > > this > > >> system by restarting > > >> > > >> > > >> RHEL 5.3 Kernel 2.6.18-128.el5 > > >> OCFS2 Versions > > >> ocfs2console-1.4.3-1.el5 > > >> ocfs2-2.6.18-128.el5-1.4.2-1.el5 > > >> ocfs2-tools-1.4.3-1.el5 > > >> > > >> Why does this show all device paths? Is there anyway to tell OCFS2 > > to > > >> ignore the /dev/sd* devices ? > > >> $ mounted.ocfs2 -d > > >> Device FS UUID > > Label > > >> /dev/sdf1 ocfs2 2eaddbd4-fac6-4c83-a86d-357215730b23 > > >> /dev/dm-25 ocfs2 2eaddbd4-fac6-4c83-a86d-357215730b23 > > >> /dev/sdaj1 ocfs2 2eaddbd4-fac6-4c83-a86d-357215730b23 > > >> /dev/sdd1 ocfs2 199f76a6-280a-46c6-812e-50712170a823 > > >> /dev/dm-32 ocfs2 199f76a6-280a-46c6-812e-50712170a823 > > >> /dev/sdai1 ocfs2 199f76a6-280a-46c6-812e-50712170a823 > > >> > > > > > > _______________________________________________ > > > Ocfs2-users mailing list > > > Ocfs2-users@oss.oracle.com > > > http://oss.oracle.com/mailman/listinfo/ocfs2-users > > > > > > > > > _______________________________________________ > > Ocfs2-users mailing list > > Ocfs2-users@oss.oracle.com > > http://oss.oracle.com/mailman/listinfo/ocfs2-users > > _______________________________________________ > Ocfs2-users mailing list > Ocfs2-users@oss.oracle.com > http://oss.oracle.com/mailman/listinfo/ocfs2-users _______________________________________________ Ocfs2-users mailing list Ocfs2-users@oss.oracle.com http://oss.oracle.com/mailman/listinfo/ocfs2-users