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Forum Discussion
edkedk
Jul 20, 2016Tutor
btrfs_merge_bio_hook+a0 error, recovery possible?
Hi, I have a ReadyNAS 204 with the btrfs_merge_bio_hook+a0 error. After reboot I can ssh into the box, but the web interface does not load and the data volume is not mounted. Output of cat /p...
- Aug 01, 2016
Eventually I used --path-regex to restore specific directories and it worked fine. Seems that everything I wanted was copied.
JennC
Jul 20, 2016NETGEAR Employee Retired
Hello edkedk,
What's the model number and FW version?
Welcome to the community!
Regards,
mdgm-ntgr
Jul 21, 2016NETGEAR Employee Retired
Can you try booting your NAS into volume read-only mode (a boot menu option) and see if the data is then accessible?
- edkedkJul 21, 2016Tutor
HI,
Model no. is RN204, fw version 6.4.2
Booting into read-only mode results in btrfs_merge_bio_hook+a0 being displayed and the data volume not mounted.
If I move the disks to a PC running Linux, will I be able to mount the volume?
- mdgm-ntgrJul 21, 2016NETGEAR Employee Retired
Shell commands would have to be used to try and mount it or attempt to recover the data and these could just as easily be done via SSH on the RN204. However attempting to do that would be at your own risk.
Have you checked the smart stats of the disks for SMART errors?
- edkedkJul 21, 2016Tutor
I just checked smart values using smartctl and see no error on any disk.
I'd like to try to manually mount the volume. Could you assist me with the required shell commands?
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