Re: kern/57081: ZFS pool rolled back two years, all data lost since.

[Roy Marples <roy%marples.name@localhost>]

The following reply was made to PR kern/57081; it has been noted by GNATS.

From: Roy Marples <roy%marples.name@localhost>
To: Taylor R Campbell <riastradh%NetBSD.org@localhost>
Cc: gnats-bugs%NetBSD.org@localhost
Subject: Re: kern/57081: ZFS pool rolled back two years, all data lost since.
Date: Fri, 11 Nov 2022 10:23:19 +0000

 Hi Taylor, thanks for the prompt reply
 
 On 11/11/2022 10:00, Taylor R Campbell wrote:
 > 1. Can you make an archive of the vdevs, and any zpool.cache file,
 >     onto another medium just so that you don't lose anything more in
 >     the event of experimentation?
 
 Unsure how?
 I will prep a spare disk to boot from in the meantime.
 
 > 
 > 2. Did you update your bootloader according to src/UPDATING?
 >     Otherwise it won't be able to find modules from 9.99.1xx.  (This is
 >     necessary only for current kernels, and will not be needed for 10.)
 
 Sadly no.
 
 > 
 > 3. How are your disks partitions and file systems arranged and system
 >     booted?
 
 [     1.208885] wd0: GPT GUID: 31914b98-ccf9-41af-a403-43d6891c6095
 [     1.208885] dk0 at wd0: "boot", 4194304 blocks at 2048, type: ffs
 [     1.208885] dk1 at wd0: "swp", 67004416 blocks at 4196352, type: swap
 [     1.208885] dk2 at wd0: "zroot", 905572367 blocks at 71200768, type: zfs
 
 # zpool status rpool
    pool: rpool
   state: ONLINE
    scan: scrub repaired 0 in 0h11m with 0 errors on Sun Oct 18 14:27:27 2020
 config:
 
          NAME        STATE     READ WRITE CKSUM
          rpool       ONLINE       0     0     0
            dk5       ONLINE       0     0     0
 
 errors: No known data errors
 
 dk5 is my spare disk I can reuse. No idea what's on it!
 
 
 # zfs list
 NAME                    USED  AVAIL  REFER  MOUNTPOINT
 rpool                  94.5G  3.36G    23K  /rpool
 rpool/ROOT             94.5G  3.36G   405M  legacy
 rpool/ROOT/home        67.1G  3.36G  67.1G  /home
 rpool/ROOT/usr         6.03G  3.36G   434M  legacy
 rpool/ROOT/usr/obj     46.6M  3.36G  46.6M  /usr/obj
 rpool/ROOT/usr/pkg      593M  3.36G   592M  /usr/pkg
 rpool/ROOT/usr/pkgsrc  3.10G  3.36G  3.10G  /usr/pkgsrc
 rpool/ROOT/usr/src     1.26G  3.36G  1.26G  /usr/src
 rpool/ROOT/usr/tools    221M  3.36G   197M  /usr/tools
 rpool/ROOT/usr/xsrc     296M  3.36G   296M  /usr/xsrc
 rpool/ROOT/var         20.9G  3.36G  20.6G  legacy
 rpool/ROOT/var/log     2.79M  3.36G  2.63M  legacy
 rpool/ROOT/var/pbulk    273M  3.36G   273M  /var/pbulk
 rpool/ROOT/var/spool    817K  3.36G   793K  /var/spool
 rpool/ROOT/var/www       23K  3.36G    23K  /var/www
 
 > 
 > 4. Can you share output from `zdb -e -l <vdev>' and from `zdb -e -h
 >     <pool>'?
 
 # zdb -e -l /dev/dk0
 cannot open '/dev/dk0': Device busy
 # zdb -e -h rpool
 zdb: can't open 'rpool': No such file or directory
 # zdb rpool
 zdb: can't open 'rpool': Device busy
 
 > 
 > 5. Are you using a zpool.cache file?  If yes, can you try moving it
 >     out of the way and see if that changes anything?
 
 Not using one.
 
 Roy