Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.
Lars Ellenberg wrote: > > / 2004-04-14 15:09:10 -0500 > \ Todd Denniston: > > <SNIP> > > BTW When drbd puts the kernel, on the secondary machine, into > > kernel-panic and you bring the secondary machine back up... is a > > quick sync really enough??? > > good question. > probably not, and it should be written into the meta data first, so it > will ensure a full sync, or maybe even refuse to do anything until > operator confirmed: "yes, hardware *is* ok again.", and only then do the > full sync. > > Philipp and others, please comment. drbd would probably need to write something to /var/lib/drbd/afile, indicating it was about to cause a kernel panic, so it would know it did that when the system came back up. BUT, it would need to sync the /var/lib/drbd/afile just before calling the panic ... and that might block if the dev for /var/lib/drbd/ happend to be having problems too (spawn off a separate sync job, give it a half second?). > > > or should I bring drbd down and `rm /var/lib/drbd/* -f`, and then bring drbd > > back up forcing a full sync? I have been doing the rm. (for what I think is to > > keep my sanity). > > you can also request a full sync by "drbdsetup /dev/nbX replicate" > ... > Do that as root on logged in on the box that went down, correct? (just want to make sure I get the sync direction correct.) <SNIP> > No, I won't go and try to write some autodetection mechanism. > But this may be an interessting additional config thing for drbd 0.7. > Similar to "sync-group", we can have a "lo-dev-group": > This makes sense, since DRBD 0.7. does not panic by default, but > goes into "diskless" mode. If several devices share the same lo-dev, > each of them in turn would need to wait for the hw-driver retry timeout > cycle to recognize what we could have known already... That sounds like a good idea to me. -- Todd Denniston Crane Division, Naval Surface Warfare Center (NSWC Crane) Harnessing the Power of Technology for the Warfighter