On Mon, Aug 19, 2013 at 04:41:39PM +0200, Valerio Pachera wrote: > Scenario: > > cluster with 3 nodes and a vdi with some snapshots. > > Node 0 dies (and sure it didn't flush the cache). > > Before Node 0 is back on line, I remove the vdi and its snapshots! > > Once Node 0 is back, it's still showing the vdi and the snapshots. > > # collie vdi list > Name Id Size Used Shared Creation time VDI id Copies Tag > s big 2 50 GB 0.0 MB 44 MB 2013-08-19 16:12 4fd25e > 2 > s big 3 50 GB 0.0 MB 44 MB 2013-08-19 16:12 4fd25f > 2 > s big 4 50 GB 220 MB 40 MB 2013-08-19 16:12 4fd260 > 2 > s big 5 50 GB 40 MB 252 MB 2013-08-19 16:13 4fd261 > 2 > s big 6 50 GB 8.0 MB 284 MB 2013-08-19 16:13 4fd262 > 2 > s big 7 50 GB 460 MB 40 MB 2013-08-19 16:13 4fd263 > 2 > big 0 50 GB 52 MB 496 MB 2013-08-19 16:13 4fd264 2 > > If I remove a snapshot from Node 0 I get an error, but it does the job: > > # collie vdi delete -s 1 big > Failed to delete big: Failed to find requested tag > # collie vdi delete -s 2 big > Failed to delete big: Failed to find requested tag > > # collie vdi list > Name Id Size Used Shared Creation time VDI id Copies Tag > s big 3 50 GB 0.0 MB 44 MB 2013-08-19 16:12 4fd25f > 2 > s big 4 50 GB 220 MB 40 MB 2013-08-19 16:12 4fd260 > 2 > s big 5 50 GB 40 MB 252 MB 2013-08-19 16:13 4fd261 > 2 > s big 6 50 GB 8.0 MB 284 MB 2013-08-19 16:13 4fd262 > 2 > s big 7 50 GB 460 MB 40 MB 2013-08-19 16:13 4fd263 > 2 > big 0 50 GB 52 MB 496 MB 2013-08-19 16:13 4fd264 2 > > In such situation, I think it's better to clear the node data before > inserting it back on line, as if it was new. > > What do you think? We actually purge data of backend store, but not the cache. I am not sure if we should purge the cache too. For code simplicity, I favor purging cache when joining back. Thanks Yuan |