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csirac2
Volume layout with root and home in top level not working
On Fedora the default volume layout is
# btrfs subvolume list -t /
ID gen top level path
-- --- --------- ----
257 123693 5 root
258 123693 5 home
305 123659 257 var/lib/machines
snazzer --all --dry-run fails with ERROR: /root is not a btrfs subvolume and
snazzer --all --dry-run /home fails with /home/root is not a btrfs subvolume
mount /dev/sdb -o subvolid=5 /mnt and then
snazzer --all --dry-run /mnt will ignore ignores.
while snazzer --all --dry-run /mnt/root will fail with ERROR: /mnt/root is not a filesystem mountpoint same for /mnt/home
Thanks for trying snazzer on fedora. 👍 Could you post your /etc/fstab as well, please, and the output of findmnt?
I've a similar layout running on Arch Linux, so we should get this to work somehow. Btw, did you run snazzer --all --dry-run or snazzer --all --dry-run /?
@csirac2 the strange thing is that with my similar setup, I actually get no output to snazzer --all --dry-run. (I always run snazzer with specifying the target mountpoint.)
#
# /etc/fstab
# Created by anaconda on Sat Oct 15 05:01:16 2016
#
# Accessible filesystems, by reference, are maintained under '/dev/disk'
# See man pages fstab(5), findfs(8), mount(8) and/or blkid(8) for more info
#
UUID=74a743dd-61f2-4773-b168-fc6dc6269d63 / btrfs subvol=root,x-systemd.device-timeout=0,noatime,nodiratime 0 0
UUID=2bf80deb-68cf-461a-a647-0efa9952fe3a /boot ext4 defaults 1 2
UUID=B2BB-B996 /boot/efi vfat umask=0077,shortname=winnt 0 2
UUID=74a743dd-61f2-4773-b168-fc6dc6269d63 /home btrfs subvol=home,x-systemd.device-timeout=0,noatime,nodiratime 0 0
/dev/mapper/luks-71506272-8821-40b8-980c-5a8752268266 swap swap defaults,x-systemd.device-timeout=0 0 0
TARGET SOURCE FSTYPE OPTIONS
/ /dev/mapper/luks-6d7b5391-2c54-46cc-81f4-065251e55fa3[/root] btrfs rw,noatime,nodiratime,seclabel,ssd,space_cache,subvolid=257,subvol=/root
??????/sys sysfs sysfs rw,nosuid,nodev,noexec,relatime,seclabel
??? ??????/sys/kernel/security securityfs securityfs rw,nosuid,nodev,noexec,relatime
??? ??????/sys/fs/cgroup tmpfs tmpfs ro,nosuid,nodev,noexec,seclabel,mode=755
??? ??? ??????/sys/fs/cgroup/systemd cgroup cgroup rw,nosuid,nodev,noexec,relatime,xattr,release_agent=/usr/lib/systemd/systemd-cgroups-agent,name=systemd
??? ??? ??????/sys/fs/cgroup/memory cgroup cgroup rw,nosuid,nodev,noexec,relatime,memory
??? ??? ??????/sys/fs/cgroup/freezer cgroup cgroup rw,nosuid,nodev,noexec,relatime,freezer
??? ??? ??????/sys/fs/cgroup/cpuset cgroup cgroup rw,nosuid,nodev,noexec,relatime,cpuset
??? ??? ??????/sys/fs/cgroup/net_cls,net_prio cgroup cgroup rw,nosuid,nodev,noexec,relatime,net_cls,net_prio
??? ??? ??????/sys/fs/cgroup/hugetlb cgroup cgroup rw,nosuid,nodev,noexec,relatime,hugetlb
??? ??? ??????/sys/fs/cgroup/pids cgroup cgroup rw,nosuid,nodev,noexec,relatime,pids
??? ??? ??????/sys/fs/cgroup/blkio cgroup cgroup rw,nosuid,nodev,noexec,relatime,blkio
??? ??? ??????/sys/fs/cgroup/devices cgroup cgroup rw,nosuid,nodev,noexec,relatime,devices
??? ??? ??????/sys/fs/cgroup/cpu,cpuacct cgroup cgroup rw,nosuid,nodev,noexec,relatime,cpu,cpuacct
??? ??? ??????/sys/fs/cgroup/perf_event cgroup cgroup rw,nosuid,nodev,noexec,relatime,perf_event
??? ??????/sys/fs/pstore pstore pstore rw,nosuid,nodev,noexec,relatime,seclabel
??? ??????/sys/firmware/efi/efivars efivarfs efivarfs rw,nosuid,nodev,noexec,relatime
??? ??????/sys/fs/selinux selinuxfs selinuxfs rw,relatime
??? ??????/sys/kernel/debug debugfs debugfs rw,relatime,seclabel
??? ??????/sys/kernel/config configfs configfs rw,relatime
??? ??????/sys/fs/fuse/connections fusectl fusectl rw,relatime
??????/proc proc proc rw,nosuid,nodev,noexec,relatime
??? ??????/proc/sys/fs/binfmt_misc systemd-1 autofs rw,relatime,fd=26,pgrp=1,timeout=0,minproto=5,maxproto=5,direct,pipe_ino=14067
??? ??????/proc/fs/nfsd nfsd nfsd rw,relatime
??????/dev devtmpfs devtmpfs rw,nosuid,seclabel,size=4030340k,nr_inodes=1007585,mode=755
??? ??????/dev/shm tmpfs tmpfs rw,nosuid,nodev,seclabel
??? ??????/dev/pts devpts devpts rw,nosuid,noexec,relatime,seclabel,gid=5,mode=620,ptmxmode=000
??? ??????/dev/hugepages hugetlbfs hugetlbfs rw,relatime,seclabel
??? ??????/dev/mqueue mqueue mqueue rw,relatime,seclabel
??????/run tmpfs tmpfs rw,nosuid,nodev,seclabel,mode=755
??? ??????/run/user/42 tmpfs tmpfs rw,nosuid,nodev,relatime,seclabel,size=808396k,mode=700,uid=42,gid=42
??? ??????/run/user/1000 tmpfs tmpfs rw,nosuid,nodev,relatime,seclabel,size=808396k,mode=700,uid=1000,gid=1000
??? ??????/run/user/1000/gvfs gvfsd-fuse fuse.gvfsd-fuse rw,nosuid,nodev,relatime,user_id=1000,group_id=1000
??????/tmp tmpfs tmpfs rw,nosuid,nodev,seclabel
??????/home /dev/mapper/luks-6d7b5391-2c54-46cc-81f4-065251e55fa3[/home] btrfs rw,noatime,nodiratime,seclabel,ssd,space_cache,subvolid=258,subvol=/home
??????/boot /dev/sda2 ext4 rw,relatime,seclabel,data=ordered
??? ??????/boot/efi /dev/sda1 vfat rw,relatime,fmask=0077,dmask=0077,codepage=437,iocharset=ascii,shortname=winnt,errors=remount-ro
??????/var/lib/nfs/rpc_pipefs sunrpc rpc_pipefs rw,relatime
??????/mnt /dev/mapper/luks-6d7b5391-2c54-46cc-81f4-065251e55fa3 btrfs rw,relatime,seclabel,ssd,space_cache,subvolid=5,subvol=/
??????/var/lib/docker/btrfs /dev/mapper/luks-6d7b5391-2c54-46cc-81f4-065251e55fa3[/root/var/lib/docker/btrfs] btrfs rw,noatime,nodiratime,seclabel,ssd,space_cache,subvolid=257,subvol=/root/var/lib/docker/btrfs
I ran booth and they gave the same output
I'm confused. What I use to circumvent the top level subvolumes issue is to mount my disk via fstab to /run/systemfs, and run snazzer on that mountpoint, so exactly what you tried with your /mnt experiment.
Hopefully @csirac2 can shed some light on what's actually happening there next weekend, and why root is always appended…
To complete the view, you could post df -t btrfs, maybe luks encryption is interfering with that somehow? I don't use luks encryption, which might be the difference between our systems.
Using /mnt works-ish i modified exclude.patterns var/cache to root/var/cache and now taking snapshots seems to work.
But then snazzer-receive fails
snazzer-receive host --all /mnt/systemfs
subvolume mnt/systemfs:
mkdir: created directory 'mnt'
Create subvolume 'mnt/systemfs'
mkdir: created directory 'mnt/systemfs/.snapshotz'
At subvol 2016-11-27T235638+0100
1 of 1 snapshots received (0 pruned, 1 considered, 0 skipped)
appending measurements...
ERROR running:
ssh "host" "sudo -n grep -srl '^> on host at ' '/mnt/systemfs/.snapshotz/.measurements/'"
as does snazzer-measure
snazzer-measure /mnt/systemfs
################################################################################
> on host at 2016-11-28T002058+0100, du bytes:
(du -bs --one-file-system --exclude-from '/mnt/systemfs/.snapshot_measurements.exclude' '/mnt/systemfs')
cat: /mnt/systemfs/.snapshot_measurements.exclude: No such file or directory
80 /mnt/systemfs
tar: /mnt/systemfs/.snapshot_measurements.exclude: No such file or directory
tar: Error is not recoverable: exiting now
list-snapshots seems to work
snazzer --list-snapshots --all /mnt/systemfs
/mnt/systemfs/.snapshotz/2016-11-27T235638+0100
/mnt/systemfs/root/.snapshotz/2016-11-27T235638+0100
/mnt/systemfs/home/.snapshotz/2016-11-27T235638+0100
/mnt/systemfs/root/var/lib/machines/.snapshotz/2016-11-27T235638+0100
42 subvolumes excluded in /mnt/systemfs by /etc/snazzer/exclude.patterns.
root seems to be appended because it is the first subvolume reported by btrfs subvolume list
# sudo btrfs subvolume list /
ID 257 gen 124374 top level 5 path root
ID 258 gen 124374 top level 5 path home
ID 305 gen 124302 top level 257 path var/lib/machines
ID 398 gen 124295 top level 5 path .snapshotz/2016-11-27T235638+0100
ID 399 gen 124298 top level 257 path .snapshotz/2016-11-27T235638+0100
ID 400 gen 124300 top level 258 path home/.snapshotz/2016-11-27T235638+0100
ID 401 gen 124301 top level 305 path var/lib/machines/.snapshotz/2016-11-27T235638+0100
and is even when /home is specified
btrfs subvolume list /home
ID 257 gen 124377 top level 5 path root
ID 258 gen 124377 top level 5 path home
ID 305 gen 124302 top level 257 path root/var/lib/machines
ID 398 gen 124295 top level 5 path .snapshotz/2016-11-27T235638+0100
ID 399 gen 124298 top level 257 path root/.snapshotz/2016-11-27T235638+0100
ID 400 gen 124300 top level 258 path .snapshotz/2016-11-27T235638+0100
ID 401 gen 124301 top level 305 path root/var/lib/machines/.snapshotz/2016-11-27T235638+0100
btrfs subvolume list /home -o returns only actual subvolumes but this causes btrfs subvolume list / -o to not include /home which would probably make --all not work as intended
df -t btrfs
Filesystem 1K-blocks Used Available Use% Mounted on
/dev/dm-0 236752896 48858680 187165944 21% /
/dev/dm-0 236752896 48858680 187165944 21% /home
/dev/dm-0 236752896 48858680 187165944 21% /mnt/systemfs
Research results: btrfs subvolume list <path> lists all subvolumes on -o reduces that to subvolumes below
Thanks for the contributions - yes indeed, you have discovered that I haven't been testing snazzer with this layout. Now that snazzer appears to have people trying it, I will work on improving the testing :)
Addressing this requires some thought - it seems like a regression I thought I had already fixed. Will work on this once the other two PRs are done. I have some ansible automation I will need to bring into our tests somehow. Thanks again
I run into a similar situation. OS is CentOS 7.3. I created a btrfs filesystem named tank. Then I created two subvolumes under tank for var and home. My /etc/fstab is as below:
[root@localhost /]# cat /etc/fstab
UUID=24ac7a7f-4a8b-4a56-814d-f4195d2f5690 / ext4 defaults 1 1 LABEL=tank /tank btrfs defaults 0 0 LABEL=tank /var btrfs defaults,subvolid=258 0 0 LABEL=tank /home btrfs defaults,subvolid=259 0 0 UUID=021b1b78-4b80-44af-b11a-389a62d464ca swap swap defaults 0 0
[root@localhost /]# btrfs subvolume list -t /tank ID gen top level path -- --- --------- ---- 258 453 5 var 259 455 5 home
[root@localhost /]# snazzer --all --dry-run /home cat <<EXCL | tee '/home/.snapshot_measurements.exclude' >/dev/null
EXCL btrfs subvolume snapshot -r '/home' '/home/.snapshotz/2017-05-24T015701+0800' rm '/home/.snapshot_measurements.exclude' ERROR: /home/var is not a btrfs subvolume
[root@localhost /]# snazzer --all --dry-run /var cat <<EXCL | tee '/var/.snapshot_measurements.exclude' >/dev/null
EXCL btrfs subvolume snapshot -r '/var' '/var/.snapshotz/2017-05-24T015857+0800' rm '/var/.snapshot_measurements.exclude' ERROR: /var/var is not a btrfs subvolume
