Hi, I tried to reboot the machine, but bcache is still dead. /sys/block/bcache0/bcache/state reports "clean" (RAID5) /sys/block/bcache1/bcache/state reports "no cache" (SAN RAID10) I did not mention before that the SAN is used like a DAS, and it isn't shared with other machines. There's just one server accessing it. Regards, Michele Il Fri, 07 Oct 2016 10:46:39 +0000, Michele Brodoloni ha scritto: > Hello, > I have bcache running on a Debian 8.0 x86_64 with kernel 4.4.16. > I got 2x Samsung PRO 850 250gb in hardware RAID0 acting as cache device > for 1) a local RAID5 volume 2) a SAN RAID10 volume in active/backup > multipath fiber channel > > I noticed today that SAN backing devices got detached from cache: > > # bcache-super-show /dev/sdc1 sb.magic ok sb.first_sector 8 [match] > sb.csum 2D71F678442855F6 [match] > sb.version 3 [cache device] > dev.label (empty) > dev.uuid c3dd7b4e-04e0-4578-a0ce-b35a5745e459 dev.sectors_per_block 1 > dev.sectors_per_bucket 1024 dev.cache.first_sector 1024 > dev.cache.cache_sectors 629144576 dev.cache.total_sectors 629145600 > dev.cache.ordered yes dev.cache.discard no dev.cache.pos 0 > dev.cache.replacement 0 [lru] cset.uuid > 7eb257b3-940d-42ca-ab23-52752f8b17f8 > > # bcache-super-show /dev/sdd1 sb.magic ok sb.first_sector 8 [match] > sb.csum 514C0F59BC7C1938 [match] > sb.version 1 [backing device] > dev.label (empty) > dev.uuid 904aaaa4-473a-446d-aad5-4e55cde972a8 dev.sectors_per_block 1 > dev.sectors_per_bucket 1024 dev.data.first_sector 16 dev.data.cache_mode > 0 [writethrough] > dev.data.cache_state 0 [detached] cset.uuid > 00000000-0000-0000-0000-000000000000 > > # bcache-super-show /dev/sde1 sb.magic ok sb.first_sector 8 [match] > sb.csum 514C0F59BC7C1938 [match] > sb.version 1 [backing device] > dev.label (empty) > dev.uuid 904aaaa4-473a-446d-aad5-4e55cde972a8 dev.sectors_per_block 1 > dev.sectors_per_bucket 1024 dev.data.first_sector 16 dev.data.cache_mode > 0 [writethrough] > dev.data.cache_state 0 [detached] cset.uuid > 00000000-0000-0000-0000-000000000000 > > (Obviously /dev/sdd1 and /dev/sde1 are the same device but with > different path) > > Another side effect is that my syslog, kern.log logfiles are eating all > my root partition space with messages like this: > > Oct 7 12:27:31 lnx kernel: [2300151.278097] bcache: bch_btree_gc() gc > failed! > > > What can be done to troubleshoot this issue? > > Regards, > Michele -- To unsubscribe from this list: send the line "unsubscribe linux-bcache" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
