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Distribution: Cinnamon Mint 20.1 (Laptop) and 20.2 (Desktop)
Posts: 1,634
Rep:
Timeshift problem; disk unmounts itself.
I've been running Timeshift since way back in 2018 with the data stored on an external USB 500Gb disk I rescued from my old Virgin Media box. (When it was upgraded they didn't want the old box back, recycle it they said so I kept the disk and chucked the rest.) The disk has two partitions, one 315Gb EXT4 used for timeshift and a 185Gb NTFS one used for general storage. I configured Timeshift to run weekly snapshots and hold on to three over and above the original one full manually created one.
This has been working fine for the last couple of years but now when it runs, either scheduled or manually instigated, everything appears to be working then the disk (both partitions) suddenly disappears from the desktop with a loud "beep" and Timestamp sits twiddling its thumbs for a while. The partitions eventually re-appear but no data is saved. See the rather long dmesg output below:
I can read and write data to the NTFS partition but the EXT4 one is owned by root so read only to me as a user, is this normal for Timeshift or is it because the partition was remounted read only as per the dmesg output above?
Does it have to be available to the user as Read/Write for Timeshift to work?
I've tried reformatting the EXT partition but the disk still gets dropped during a snapshot.
The disk itself appears to be fine, see Smartctrl report below:
Code:
smartctl 6.5 2016-01-24 r4214 [x86_64-linux-4.15.0-106-generic] (local build)
Copyright (C) 2002-16, Bruce Allen, Christian Franke, www.smartmontools.org
=== START OF INFORMATION SECTION ===
Model Family: Western Digital Caviar Blue (SATA)
Device Model: WDC WD5000AAKS-00TMA0
Serial Number: WD-WCAPW4347673
LU WWN Device Id: 5 0014ee 1aaeb7a86
Firmware Version: 12.01C01
User Capacity: 500,107,862,016 bytes [500 GB]
Sector Size: 512 bytes logical/physical
Device is: In smartctl database [for details use: -P show]
ATA Version is: ATA/ATAPI-7 (minor revision not indicated)
Local Time is: Tue Jun 30 11:41:24 2020 BST
SMART support is: Available - device has SMART capability.
SMART support is: Enabled
=== START OF READ SMART DATA SECTION ===
SMART overall-health self-assessment test result: PASSED
General SMART Values:
Offline data collection status: (0x82) Offline data collection activity
was completed without error.
Auto Offline Data Collection: Enabled.
Self-test execution status: ( 0) The previous self-test routine completed
without error or no self-test has ever
been run.
Total time to complete Offline
data collection: (12000) seconds.
Offline data collection
capabilities: (0x7b) SMART execute Offline immediate.
Auto Offline data collection on/off support.
Suspend Offline collection upon new
command.
Offline surface scan supported.
Self-test supported.
Conveyance Self-test supported.
Selective Self-test supported.
SMART capabilities: (0x0003) Saves SMART data before entering
power-saving mode.
Supports SMART auto save timer.
Error logging capability: (0x01) Error logging supported.
General Purpose Logging supported.
Short self-test routine
recommended polling time: ( 2) minutes.
Extended self-test routine
recommended polling time: ( 150) minutes.
Conveyance self-test routine
recommended polling time: ( 6) minutes.
SCT capabilities: (0x303f) SCT Status supported.
SCT Error Recovery Control supported.
SCT Feature Control supported.
SCT Data Table supported.
SMART Attributes Data Structure revision number: 16
Vendor Specific SMART Attributes with Thresholds:
ID# ATTRIBUTE_NAME FLAG VALUE WORST THRESH TYPE UPDATED WHEN_FAILED RAW_VALUE
1 Raw_Read_Error_Rate 0x000f 200 200 051 Pre-fail Always - 0
3 Spin_Up_Time 0x0003 173 168 021 Pre-fail Always - 6341
4 Start_Stop_Count 0x0032 096 096 000 Old_age Always - 4457
5 Reallocated_Sector_Ct 0x0033 200 200 140 Pre-fail Always - 0
7 Seek_Error_Rate 0x000e 200 200 051 Old_age Always - 0
9 Power_On_Hours 0x0032 065 065 000 Old_age Always - 26082
10 Spin_Retry_Count 0x0012 100 100 051 Old_age Always - 0
11 Calibration_Retry_Count 0x0012 100 100 051 Old_age Always - 0
12 Power_Cycle_Count 0x0032 096 096 000 Old_age Always - 4274
192 Power-Off_Retract_Count 0x0032 199 199 000 Old_age Always - 922
193 Load_Cycle_Count 0x0032 199 199 000 Old_age Always - 4481
194 Temperature_Celsius 0x0022 130 100 000 Old_age Always - 20
196 Reallocated_Event_Count 0x0032 200 200 000 Old_age Always - 0
197 Current_Pending_Sector 0x0012 200 200 000 Old_age Always - 0
198 Offline_Uncorrectable 0x0010 200 200 000 Old_age Offline - 0
199 UDMA_CRC_Error_Count 0x003e 200 200 000 Old_age Always - 24
200 Multi_Zone_Error_Rate 0x0008 200 200 051 Old_age Offline - 0
SMART Error Log Version: 1
No Errors Logged
SMART Self-test log structure revision number 1
Num Test_Description Status Remaining LifeTime(hours) LBA_of_first_error
# 1 Extended offline Completed without error 00% 26072 -
# 2 Extended offline Completed without error 00% 25873 -
# 3 Extended offline Interrupted (host reset) 60% 25834 -
# 4 Extended offline Interrupted (host reset) 80% 25834 -
# 5 Conveyance offline Completed without error 00% 25826 -
# 6 Short offline Completed without error 00% 25824 -
SMART Selective self-test log data structure revision number 1
SPAN MIN_LBA MAX_LBA CURRENT_TEST_STATUS
1 0 0 Not_testing
2 0 0 Not_testing
3 0 0 Not_testing
4 0 0 Not_testing
5 0 0 Not_testing
Selective self-test flags (0x0):
After scanning selected spans, do NOT read-scan remainder of disk.
If Selective self-test is pending on power-up, resume after 0 minute delay.
The two incomplete Extended tests was me giving up at one o'clock in the morning a couple of times and shutting down.
I'm running Mint 18.3 on my Z400 Workstation. Kernel 4.15.0-107-generic at present though the problem happened with several previous versions as well.
Any advice on where I should go now would be appreciated,
Play Bonny!
Last edited by Soadyheid; 07-03-2020 at 07:24 PM.
Reason: change quote to code tags as requested.
First up, change that [quote] tag to [code] so we can make sense of the SMART output.
I'd say you have a dodgy cable/connector - maybe flexing over time has done some damage. Might be power as well - do you use an external power plug ?.
As for the filesystem going ro, that is probably because you told it to - check fstab.
Distribution: Cinnamon Mint 20.1 (Laptop) and 20.2 (Desktop)
Posts: 1,634
Original Poster
Rep:
Hi sygOO, thanks for the reply. Tags changed as requested!
The cable to the disk is a bog standard USB-A to USB-B cable, I've reseated the internal wiring within the external disk case and the power cable is a plug in power brick, it all sits beside my workstation and, as nothing ever moves, shouldn't flex. The problem only happens when Timeshift runs so I don't think it's a connection/cabling problem. My system's running for about twelve hours a day during which the disk's fine.
The disk isn't an entry in my fstab: sda is my main disk, sdg the Timeshift one.
Code:
/etc $ cat fstab
# /etc/fstab: static file system information.
#
# Use 'blkid' to print the universally unique identifier for a
# device; this may be used with UUID= as a more robust way to name devices
# that works even if disks are added and removed. See fstab(5).
#
# <file system> <mount point> <type> <options> <dump> <pass>
# / was on /dev/sda3 during installation
UUID=a37d1251-ba0e-42de-81c1-5c62e58f1e38 / ext4 errors=remount-ro 0 1
# /home was on /dev/sda4 during installation
UUID=4f88eaa4-ad4e-4898-b4d6-2f0ef6838ddc /home ext4 defaults 0 2
It's powered on before my Z400 workstation and being USB connected, automounts.
Code:
~ $ mount
sysfs on /sys type sysfs (rw,nosuid,nodev,noexec,relatime)
proc on /proc type proc (rw,nosuid,nodev,noexec,relatime)
udev on /dev type devtmpfs (rw,nosuid,relatime,size=8172068k,nr_inodes=2043017,mode=755)
devpts on /dev/pts type devpts (rw,nosuid,noexec,relatime,gid=5,mode=620,ptmxmode=000)
tmpfs on /run type tmpfs (rw,nosuid,noexec,relatime,size=1640684k,mode=755)
none on /dev/.bootchart/proc type proc (rw,relatime)
/dev/sda3 on / type ext4 (rw,relatime,errors=remount-ro,data=ordered)
securityfs on /sys/kernel/security type securityfs (rw,nosuid,nodev,noexec,relatime)
tmpfs on /dev/shm type tmpfs (rw,nosuid,nodev)
tmpfs on /run/lock type tmpfs (rw,nosuid,nodev,noexec,relatime,size=5120k)
tmpfs on /sys/fs/cgroup type tmpfs (rw,mode=755)
cgroup on /sys/fs/cgroup/systemd type cgroup (rw,nosuid,nodev,noexec,relatime,xattr,release_agent=/lib/systemd/systemd-cgroups-agent,name=systemd)
pstore on /sys/fs/pstore type pstore (rw,nosuid,nodev,noexec,relatime)
cgroup on /sys/fs/cgroup/cpuset type cgroup (rw,nosuid,nodev,noexec,relatime,cpuset,clone_children)
cgroup on /sys/fs/cgroup/cpu,cpuacct type cgroup (rw,nosuid,nodev,noexec,relatime,cpu,cpuacct)
cgroup on /sys/fs/cgroup/memory type cgroup (rw,nosuid,nodev,noexec,relatime,memory)
cgroup on /sys/fs/cgroup/net_cls,net_prio type cgroup (rw,nosuid,nodev,noexec,relatime,net_cls,net_prio)
cgroup on /sys/fs/cgroup/hugetlb type cgroup (rw,nosuid,nodev,noexec,relatime,hugetlb,release_agent=/run/cgmanager/agents/cgm-release-agent.hugetlb)
cgroup on /sys/fs/cgroup/devices type cgroup (rw,nosuid,nodev,noexec,relatime,devices)
cgroup on /sys/fs/cgroup/rdma type cgroup (rw,nosuid,nodev,noexec,relatime,rdma,release_agent=/run/cgmanager/agents/cgm-release-agent.rdma)
cgroup on /sys/fs/cgroup/freezer type cgroup (rw,nosuid,nodev,noexec,relatime,freezer)
cgroup on /sys/fs/cgroup/perf_event type cgroup (rw,nosuid,nodev,noexec,relatime,perf_event,release_agent=/run/cgmanager/agents/cgm-release-agent.perf_event)
cgroup on /sys/fs/cgroup/pids type cgroup (rw,nosuid,nodev,noexec,relatime,pids,release_agent=/run/cgmanager/agents/cgm-release-agent.pids)
cgroup on /sys/fs/cgroup/blkio type cgroup (rw,nosuid,nodev,noexec,relatime,blkio)
systemd-1 on /proc/sys/fs/binfmt_misc type autofs (rw,relatime,fd=27,pgrp=1,timeout=0,minproto=5,maxproto=5,direct,pipe_ino=2742)
mqueue on /dev/mqueue type mqueue (rw,relatime)
debugfs on /sys/kernel/debug type debugfs (rw,relatime)
hugetlbfs on /dev/hugepages type hugetlbfs (rw,relatime,pagesize=2M)
configfs on /sys/kernel/config type configfs (rw,relatime)
fusectl on /sys/fs/fuse/connections type fusectl (rw,relatime)
/dev/sda4 on /home type ext4 (rw,relatime,data=ordered)
binfmt_misc on /proc/sys/fs/binfmt_misc type binfmt_misc (rw,relatime)
cgmfs on /run/cgmanager/fs type tmpfs (rw,relatime,size=100k,mode=755)
tmpfs on /run/user/1000 type tmpfs (rw,nosuid,nodev,relatime,size=1640684k,mode=700,uid=1000,gid=1000)
gvfsd-fuse on /run/user/1000/gvfs type fuse.gvfsd-fuse (rw,nosuid,nodev,relatime,user_id=1000,group_id=1000)
/dev/sdg2 on /media/user/1614ccd2-2f24-4474-aa2a-d2b3bb9304f24 type ext4 (rw,nosuid,nodev,relatime,data=ordered,uhelper=udisks2) <-- Timeshift partition
/dev/sdg1 on /media/user/47A9700204FC4582 type fuseblk [COLOR="red"]<-- This is the NTFS partition[/COLOR(rw,nosuid,nodev,relatime,user_id=0,group_id=0,default_permissions,allow_other,blksize=4096,uhelper=udisks2)
From above, the partition is mounted Read/Write but as the User, I can only read from it. Is this what I should expect?
Another weird thing when I look at the mount point...
Code:
user@user-HP-Z400-Workstation /media/user $ ls -al
total 204
drwxr-x---+ 51 root root 4096 Jul 4 11:46 .
drwxr-xr-x 4 root root 4096 Mar 19 2018 ..
drwxr-xr-x 3 root root 4096 Jun 29 13:09 1614ccd2-2f24-4474-aa2a-d2b3bb9304f2
drwxr-xr-x 3 root root 4096 Jun 29 17:09 1614ccd2-2f24-4474-aa2a-d2b3bb9304f21
drwxr-xr-x 3 root root 4096 Jun 29 23:09 1614ccd2-2f24-4474-aa2a-d2b3bb9304f22
drwxr-xr-x 3 root root 4096 Jul 2 15:10 1614ccd2-2f24-4474-aa2a-d2b3bb9304f23
drwxr-xr-x 4 root root 4096 Jun 29 12:27 1614ccd2-2f24-4474-aa2a-d2b3bb9304f24 <-- Timeshift Partition
drwxr-xr-x 3 root root 4096 May 28 15:17 2d2ceeb7-1b7a-41aa-84ea-a841d27ef16c
drwxr-xr-x 3 root root 4096 May 28 16:47 2d2ceeb7-1b7a-41aa-84ea-a841d27ef16c1
drwxr-xr-x 3 root root 4096 Jun 8 13:52 2d2ceeb7-1b7a-41aa-84ea-a841d27ef16c10
drwxr-xr-x 3 root root 4096 Jun 8 14:22 2d2ceeb7-1b7a-41aa-84ea-a841d27ef16c11
drwxr-xr-x 3 root root 4096 Jun 8 18:22 2d2ceeb7-1b7a-41aa-84ea-a841d27ef16c12
drwxr-xr-x 3 root root 4096 Jun 8 20:22 2d2ceeb7-1b7a-41aa-84ea-a841d27ef16c13
drwxr-xr-x 3 root root 4096 Jun 8 21:22 2d2ceeb7-1b7a-41aa-84ea-a841d27ef16c14
drwxr-xr-x 3 root root 4096 Jun 9 15:09 2d2ceeb7-1b7a-41aa-84ea-a841d27ef16c15
drwxr-xr-x 3 root root 4096 Jun 9 16:05 2d2ceeb7-1b7a-41aa-84ea-a841d27ef16c16
drwxr-xr-x 3 root root 4096 Jun 19 13:25 2d2ceeb7-1b7a-41aa-84ea-a841d27ef16c17
drwxr-xr-x 3 root root 4096 Jun 19 14:25 2d2ceeb7-1b7a-41aa-84ea-a841d27ef16c18
drwxr-xr-x 3 root root 4096 Jun 19 15:25 2d2ceeb7-1b7a-41aa-84ea-a841d27ef16c19
drwxr-xr-x 3 root root 4096 May 28 17:18 2d2ceeb7-1b7a-41aa-84ea-a841d27ef16c2
drwxr-xr-x 3 root root 4096 Jun 19 16:24 2d2ceeb7-1b7a-41aa-84ea-a841d27ef16c20
drwxr-xr-x 3 root root 4096 Jun 22 12:01 2d2ceeb7-1b7a-41aa-84ea-a841d27ef16c21
drwxr-xr-x 3 root root 4096 Jun 23 14:18 2d2ceeb7-1b7a-41aa-84ea-a841d27ef16c22
drwxr-xr-x 3 root root 4096 Jun 23 15:48 2d2ceeb7-1b7a-41aa-84ea-a841d27ef16c23
drwxr-xr-x 3 root root 4096 Jun 23 16:18 2d2ceeb7-1b7a-41aa-84ea-a841d27ef16c24
drwxr-xr-x 3 root root 4096 Jun 23 17:18 2d2ceeb7-1b7a-41aa-84ea-a841d27ef16c25
drwxr-xr-x 3 root root 4096 Jun 23 18:48 2d2ceeb7-1b7a-41aa-84ea-a841d27ef16c26
drwxr-xr-x 3 root root 4096 Jun 23 20:18 2d2ceeb7-1b7a-41aa-84ea-a841d27ef16c27
drwxr-xr-x 3 root root 4096 Jun 23 21:18 2d2ceeb7-1b7a-41aa-84ea-a841d27ef16c28
drwxr-xr-x 3 root root 4096 Jun 24 13:19 2d2ceeb7-1b7a-41aa-84ea-a841d27ef16c29
drwxr-xr-x 3 root root 4096 May 28 18:17 2d2ceeb7-1b7a-41aa-84ea-a841d27ef16c3
drwxr-xr-x 3 root root 4096 Jun 26 12:05 2d2ceeb7-1b7a-41aa-84ea-a841d27ef16c30
drwxr-xr-x 3 root root 4096 Jun 26 14:05 2d2ceeb7-1b7a-41aa-84ea-a841d27ef16c31
drwxr-xr-x 3 root root 4096 Jun 26 15:05 2d2ceeb7-1b7a-41aa-84ea-a841d27ef16c32
drwxr-xr-x 3 root root 4096 Jun 26 18:35 2d2ceeb7-1b7a-41aa-84ea-a841d27ef16c33
drwxr-xr-x 3 root root 4096 Jun 27 17:03 2d2ceeb7-1b7a-41aa-84ea-a841d27ef16c34
drwxr-xr-x 3 root root 4096 Jun 27 18:02 2d2ceeb7-1b7a-41aa-84ea-a841d27ef16c35
drwxr-xr-x 3 root root 4096 Jun 27 19:02 2d2ceeb7-1b7a-41aa-84ea-a841d27ef16c36
drwxr-xr-x 3 root root 4096 Jun 27 23:02 2d2ceeb7-1b7a-41aa-84ea-a841d27ef16c37
drwxr-xr-x 3 root root 4096 Jun 28 00:02 2d2ceeb7-1b7a-41aa-84ea-a841d27ef16c38
drwxr-xr-x 3 root root 4096 Jun 28 16:08 2d2ceeb7-1b7a-41aa-84ea-a841d27ef16c39
drwxr-xr-x 3 root root 4096 May 28 19:17 2d2ceeb7-1b7a-41aa-84ea-a841d27ef16c4
drwxr-xr-x 3 root root 4096 Jun 28 17:08 2d2ceeb7-1b7a-41aa-84ea-a841d27ef16c40
drwxr-xr-x 3 root root 4096 Jun 28 18:08 2d2ceeb7-1b7a-41aa-84ea-a841d27ef16c41
drwxr-xr-x 3 root root 4096 Jun 28 19:08 2d2ceeb7-1b7a-41aa-84ea-a841d27ef16c42
drwxr-xr-x 3 root root 4096 May 29 19:22 2d2ceeb7-1b7a-41aa-84ea-a841d27ef16c5
drwxr-xr-x 3 root root 4096 May 29 21:22 2d2ceeb7-1b7a-41aa-84ea-a841d27ef16c6
drwxr-xr-x 3 root root 4096 Jun 7 17:17 2d2ceeb7-1b7a-41aa-84ea-a841d27ef16c7
drwxr-xr-x 3 root root 4096 Jun 7 17:46 2d2ceeb7-1b7a-41aa-84ea-a841d27ef16c8
drwxr-xr-x 3 root root 4096 Jun 7 18:16 2d2ceeb7-1b7a-41aa-84ea-a841d27ef16c9
drwxrwxrwx 1 user user 4096 Jun 29 22:30 47A9700204FC4582 <-- NTFS Partition
All these other entries in /media/user are also Timeshift "directories" though I don't know why there are so many, I've only one physical Timeshift partition which appears to have the same "ID" unless I plug it in to a different USB port. You'll note that I, as the user, have only Read/Execute permission. Does this mean that Timeshift runs as root even though I, as the user, am running it?
Hope you can shed some light on this, thanks again!
Play Bonny!
Last edited by Soadyheid; 07-04-2020 at 07:06 AM.
Reason: Tidy up and typos
OK, some random thoughts, make of them as you will.
- the disk, not the filesystem, is going away and then reconnecting. That is a hardware problem, which as would be expected under heavy writing loads breaks the filesystem. I've seen similar with both flaky connections, and power. The NTFS (and any other) is fine because it isn't active at the time.
- I'd guess power if it only breaks under sustained load on the disk.
- timeshift needs heightened priviledges for safety - that's why you get asked for your password when setting it up.
- can't explain the directory listing above. Just checked a timeshift Mint I have in the house and it doesn't look anything like that.
Distribution: Cinnamon Mint 20.1 (Laptop) and 20.2 (Desktop)
Posts: 1,634
Original Poster
Rep:
Quote:
- the disk, not the filesystem, is going away and then reconnecting.
Correct!
Quote:
- can't explain the directory listing above. Just checked a timeshift Mint I have in the house and it doesn't look anything like that.
I reckon each of the, what I assume to be, UUID directories have been generated by Timeshift, each has empty directories for boot, hourly, daily, weekly, etc, and each has a size of 32.8Kb. I'm going to try powering the external disk off and clearing out all the /media/user/<UUID stuff> and see what happens when I re-activate the disk and try for a manual snapshot. Just like if you do a backup and "aim" it at the wrong place by mistyping the destination, rather than backing up to a disk, it backs up to a rather large file! Interesting...
Distribution: Cinnamon Mint 20.1 (Laptop) and 20.2 (Desktop)
Posts: 1,634
Original Poster
Rep:
Update...
I've now cleaned my /media/user directory. I powered the external USB disk down and emptied the directory completely. Each weird UUID entry contained a timeshift directory which in turn contained a snapshot-boot, snapshot-daily, snapshot-hourly, snapshot-monthly, snapshot-ondemand and snapshot-weekly directories, all empty.
This seems to confirm my theory that Timeshift was generating and writing to a file (directory) rather than the physical disk.
I've since powered the disk back up and completed an on-demand snapshot of my home directory without any problems, no random unmounts or disconnects. dmesg is clean, no warnings or anything untoward. I then set a schedule to give me three weekly snapshots including /root and all hidden files. I then left my system for a couple of hours and lo, there's now my first weekly snapshot as well!
I'm still at a loss as to why it happened but so far it looks like I've won a watch!
Distribution: Cinnamon Mint 20.1 (Laptop) and 20.2 (Desktop)
Posts: 1,634
Original Poster
Rep:
Rats!
Rats! It's now back again doing the weird umounts plus adding UUIDs to my /media/user directory.
I tried running a manual snapshot which sort of looked like it was working except that it was still going after 11 hours with about a third of the files sync'd (Does a manual snapshot run a complete "backup" or does it just compare files with the original major "backup" to do a sort of incremental job?) That's what it looked like it was doing. Transfer to sdg, my USB connected Timeshift drive was about 3.5Mbs Max but usually less than 1Mbs.
When I eventually gave up (after the 11 hours!) the completion ETA had ramped up to over 24hrs to go!
Looks like I'm going to have to blow everything away and run a fresh manual snapshot.
Distribution: Cinnamon Mint 20.1 (Laptop) and 20.2 (Desktop)
Posts: 1,634
Original Poster
Rep:
Final update and Current observations.
Sorry to resurrect this thread but I thought it might be worth it in case others experience something similar...
The disk kept dropping out and failing the Timeshift updates to the point where I couldn't mount it any more so syg00's diagnosis proved correct; duff disk. Thanks syg00!
Observations:
Other seemingly unrelated problems I'd been having, my system wouldn't always boot cleanly, sometimes freezing occasionally with panic messages now appear resolved as well. The external USB disk was always powered up prior to booting so I reckon it's been the cause of that even though the hard drive has higher boot list priority.
I've now replaced the faulty disk with another set top box drive, this time a 1Tb 2 1/2" one and so far everything's looking good with the system booting clean each time now. (Hope I haven't tempted providence here!)
Timeshift back working fine so hopefully a permanent solution!
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