Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.
On 16/07/2013 14:55, Brian Candler wrote: > > * Check /proc/drbd on target, require network is Connected and local > disk is UpToDate. [No check on source?] > * on target: drbdsetup <dev> secondary (just to be sure?). No wait or > status check? > * on both nodes: drbdsetup <dev> disconnect. No wait or status check? Actually it does wait for GetProcStatus().is_standalone (i.e. connection status StandAlone) > * on both nodes: drbdsetup <dev> connect. Poll /proc/drbd until > connected or syncing More precisely, the code is doing the following on both sides (roughly simultaneously) to reconnect in multi-master mode: drbdsetup <dev> syncer -r 61440 --create-device drbdsetup <dev> net ipv4:x:x ipv4:y:y C -A discard-zero-changes -B consensus --create-device -m -a md5 -x XXXXXX You said: " Apparently a node was promoted right in the middle of a resync handshake, and did not like that at all." Now, I'm not clear which bit is the "promotion": It looks like "drbdsetup <dev> connect ... -m" both reconnects *and* promotes to master in one step. Now if there has been a write to the primary disk during the short time period when the secondary is disconnected from the primary, and then we reconnect in dual-master mode, then it's expected to do some resync along with the promotion. This appears to work: if I configure the VM to write aggressively to disk, then migrate, I see it goes through a resync phase: 0: cs:Connected ro:Secondary/Primary ds:UpToDate/UpToDate C r----- 0: cs:StandAlone ro:Secondary/Unknown ds:UpToDate/DUnknown r----- 0: cs:WFConnection ro:Secondary/Unknown ds:UpToDate/DUnknown C r----- 0: cs:SyncTarget ro:Primary/Primary ds:Inconsistent/UpToDate C r----- 0: cs:Connected ro:Primary/Primary ds:UpToDate/UpToDate C r----- 0: cs:StandAlone ro:Primary/Unknown ds:UpToDate/DUnknown r----- 0: cs:WFBitMapS ro:Primary/Secondary ds:UpToDate/Consistent C r----- 0: cs:Connected ro:Primary/Secondary ds:UpToDate/UpToDate C r----- So the race seems to be elsewhere. To answer your other question: no I've not tried building any other version of drbd, I'm just using the stock one in Debian Wheezy. Regards, Brian. -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.linbit.com/pipermail/drbd-user/attachments/20130716/956a4d83/attachment.htm>