Hi all,
I have an odd interaction on a CentOS 7 file server. The basic setup is a minimal 7.x install. I have 4 internal drives (/dev/sd[a-d]) configured in a RAID5 and mounted locally on /data. This is exported via NFS to ~12 workstations which use the exported file systems for /home. I have an external drive connected via USB (/dev/sde) and mounted on /rsnapshot. I use rsnapshot to back up the RAID5 to the external drive periodically. I also export /rsnapshot (read only) to the workstations so users can grab a backup copy of /home data if needed. These two mounts (/data and /rsnapshot) should be independent of each other. However, a couple of times now I've had somebody accidentally unplug my backup drive (sde), which causes NFS to shut down. Here are the messages entries when this happens.
Oct 28 16:34:12 linux-fs01 kernel: xhci_hcd 0000:00:14.0: Cannot set link state. Oct 28 16:34:12 linux-fs01 kernel: usb usb4-port2: cannot disable (err = -32) Oct 28 16:34:12 linux-fs01 kernel: usb 4-2: USB disconnect, device number 2 Oct 28 16:34:17 linux-fs01 systemd: Stopping NFS server and services... Oct 28 16:34:17 linux-fs01 systemd: Stopped NFS server and services. Oct 28 16:34:17 linux-fs01 systemd: Stopping NFSv4 ID-name mapping service... Oct 28 16:34:17 linux-fs01 systemd: Stopping NFS Mount Daemon... Oct 28 16:34:17 linux-fs01 systemd: Stopped NFSv4 ID-name mapping service. Oct 28 16:34:17 linux-fs01 rpc.mountd[10570]: Caught signal 15, un-registering and exiting. Oct 28 16:34:17 linux-fs01 systemd: Stopped NFS Mount Daemon. Oct 28 16:34:17 linux-fs01 systemd: Stopped target Local File Systems. Oct 28 16:34:17 linux-fs01 systemd: Unmounting /rsnapshot... Oct 28 16:34:17 linux-fs01 kernel: XFS (sde1): Unmounting Filesystem Oct 28 16:34:19 linux-fs01 kernel: XFS (sde1): metadata I/O error: block 0x2800ccac8 ("xlog_iodone") error 5 numblks 64 Oct 28 16:34:19 linux-fs01 kernel: XFS (sde1): xfs_do_force_shutdown(0x2) called from line 1221 of file fs/xfs/xfs_log.c. Return address = 0xffffffffc06cec30 Oct 28 16:34:19 linux-fs01 kernel: XFS (sde1): Log I/O Error Detected. Shutting down filesystem Oct 28 16:34:19 linux-fs01 kernel: XFS (sde1): Please umount the filesystem and rectify the problem(s) Oct 28 16:34:19 linux-fs01 kernel: XFS (sde1): Unable to update superblock counters. Freespace may not be correct on next mount. Oct 28 16:34:20 linux-fs01 systemd: Unmounted /rsnapshot. Oct 28 16:34:20 linux-fs01 kernel: nfsd: last server has exited, flushing export cache
Should it be expected that NFS stops when one of the exports is unmounted? I don't think so. Below is some more info on the setup. Getting another eye on this would be much appreciated.
Darby
/etc/fstab entries
/dev/md/Storage /data xfs defaults 0 0 LABEL=rsnapshot /rsnapshot xfs defaults 0 0
/etc/exports
/data 10.0.223.0/22(rw,async,no_root_squash) /rsnapshot 10.0.223.0/22(ro,sync,no_root_squash)
mdrad info
[root@linux-fs01 ~]# cat /proc/mdstat Personalities : [raid6] [raid5] [raid4] md125 : active raid5 sda[3] sdb[2] sdc[1] sdd[0] 134217728 blocks super external:/md127/0 level 5, 64k chunk, algorithm 0 [4/4] [UUUU]
md126 : active raid5 sda[3] sdb[2] sdc[1] sdd[0] 5440012288 blocks super external:/md127/1 level 5, 64k chunk, algorithm 0 [4/4] [UUUU]
md127 : inactive sda[3](S) sdb[2](S) sdd[1](S) sdc[0](S) 20804 blocks super external:imsm
unused devices: <none> [root@linux-fs01 ~]# mdadm -D /dev/md/System /dev/md/System: Container : /dev/md/imsm0, member 0 Raid Level : raid5 Array Size : 134217728 (128.00 GiB 137.44 GB) Used Dev Size : 44739328 (42.67 GiB 45.81 GB) Raid Devices : 4 Total Devices : 4
State : clean Active Devices : 4 Working Devices : 4 Failed Devices : 0 Spare Devices : 0
Layout : left-asymmetric Chunk Size : 64K
Consistency Policy : resync
UUID : b359c1f9:04655baa:52b3ed0c:5aa3c9b6 Number Major Minor RaidDevice State 3 8 0 0 active sync /dev/sda 2 8 16 1 active sync /dev/sdb 1 8 32 2 active sync /dev/sdc 0 8 48 3 active sync /dev/sdd [root@linux-fs01 ~]#