#1390 closed defect (fixed)
-d ignore doesn't work if target is a symbolic link to a device
Reported by: | rogach | Owned by: | Christian Franke |
---|---|---|---|
Priority: | minor | Milestone: | Release 7.2 |
Component: | smartd | Version: | |
Keywords: | Cc: |
Description
Setup:
$ ls -l /dev/disk/by-id/wwn-0x5000xxxx lrwxrwxrwx 9 root 2020-10-31 15:15 /dev/disk/by-id/wwn-0x5000xxxx -> ../../sda $ cat /etc/smartd.conf /dev/disk/by-id/wwn-0x5000xxxx -d ignore DEVICESCAN -a
Expected result:
Device with specified id is ignored.
Actual result:
Device (/dev/sda in this example) is not ignored.
Analysis:
This issue seems to be similar to #313.
Duplicate detection (is_duplicate_dev_idinfo) relies on populated dev_idinfo, and that is done in ATADeviceScan. But "-d ignore" bypasses any scanning altogether, thus duplicate detection is unable to deduce that /dev/sda
and /dev/disk/by-id/wwn-0x5000xxxx
are actually the same device.
There is another duplicate detection function (is_duplicate_device), but it relies on dev_names being exactly equal. I attempted to fix the issue by checking if dev_name is a symbolic link and resolving the link to actual file in such cases - seems to work correctly.
Please find attached for your consideration a patch that implements symlink resolution for device names (apply with patch --input=resolve_device_symlinks.patch
in source directory).
Attachments (1)
Change History (10)
by , 4 years ago
Attachment: | resolve_device_symlinks.patch added |
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comment:1 by , 4 years ago
Component: | all → smartd |
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Milestone: | → unscheduled |
comment:2 by , 4 years ago
The following may also work on Linux:
/dev/disk/by-id/wwn-0x5000xxxx -d ignore DEVICESCAN -d by-id -a
Requires smartmontools 7.0 or later. New Linux-only device scan option -d by-id
is only mentioned in NEWS
file, but still missing on man pages.
Try with smartctl -d by-id --scan
.
comment:3 by , 4 years ago
Of course the patch fixes this for your use case. But it assumes real POSIX path names as device names which is not always the case.
My mistake, I should have at least surrounded it with an ifdef. No problem, that patch was just a suggestion, of course you as a project owner are more familiar with the project specifics and architecture.
New Linux-only device scan option -d by-id
Yes, this works, thank you! One caveat: in my case I had to replace /wwn-0x00 with /ata-ST1000DM000-XXXX, because it seems id resolution prefers this form to wwn.
comment:4 by , 4 years ago
Milestone: | unscheduled → Release 7.2 |
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Owner: | set to |
Status: | new → accepted |
Work is in progress.
comment:6 by , 4 years ago
If possible, please test r5115.
Source tarballs and binaries are available at https://builds.smartmontools.org/.
comment:7 by , 4 years ago
Tested r5115, works flawlessly:
Device: /dev/sda, same as /dev/disk/by-id/wwn-0x5000xxxx, ignored
Thank you!
comment:8 by , 5 months ago
This works well for SATA drives (/dev/sdX), but not for NVME devices. Is there any change that it would get fixed?
root@nas:~# smartctl -d by-id --scan /dev/disk/by-id/ata-ST4000NE001-3CR101_WX10EGSJ -d scsi # /dev/disk/by-id/ata-ST4000NE001-3CR101_WX10EGSJ, SCSI device /dev/nvme0 -d nvme # /dev/nvme0, NVMe device
root@nas:~# ls -l /dev/nvme* crw------- 1 root root 241, 0 čen 1 15:19 /dev/nvme0 brw-rw---- 1 root disk 259, 0 čen 1 15:19 /dev/nvme0n1 brw-rw---- 1 root disk 259, 2 čen 1 15:19 /dev/nvme0n1p1 brw-rw---- 1 root disk 259, 3 čen 1 15:19 /dev/nvme0n1p2 brw-rw---- 1 root disk 259, 4 čen 1 15:19 /dev/nvme0n1p3
root@nas:~# ls -l /dev/disk/by-id/nvme* lrwxrwxrwx 1 root root 13 čen 1 15:19 /dev/disk/by-id/nvme-TS1TMTE220S_G514071565 -> ../../nvme0n1 lrwxrwxrwx 1 root root 15 čen 1 15:19 /dev/disk/by-id/nvme-TS1TMTE220S_G514071565-part1 -> ../../nvme0n1p1 lrwxrwxrwx 1 root root 15 čen 1 15:19 /dev/disk/by-id/nvme-TS1TMTE220S_G514071565-part2 -> ../../nvme0n1p2 lrwxrwxrwx 1 root root 15 čen 1 15:19 /dev/disk/by-id/nvme-TS1TMTE220S_G514071565-part3 -> ../../nvme0n1p3
Thanks for the report and the patch. Of course the patch fixes this for your use case. But it assumes real POSIX path names as device names which is not always the case. It breaks Windows builds. Unconditionally resolving symlinks to devices may also have undesired effects on existing
-M exec
scripts. I will implement a more general approach which handles this without changingcfg.dev_name
and allows platform specific hooks.