Re: how to recover a corrupted disk
much ado for nothing... It seems when I yanked the data cable, it wasn't the disk that got corrupted. It was the UEFI loader on sdcard that had become corrupted. Not sure when that had happened. This issue is documented here (https://github.com/pftf/RPi4/issues/97). I had ended up formatting the disk unnecessarily. Thanks a ton for pitching in suggestions. On Wed, Dec 1, 2021 at 7:30 PM Ian Darwin wrote: > > On Wed, Dec 01, 2021 at 01:39:39PM +0530, Sandeep Gupta wrote: > > Hello, > > All partitions except for /dev/rsd1c and /dev/rsd1i are clean. > > For /dev/rsd1c , I get "BAD SUPER BLOCK: MAGIC NUMBER WRONG". > > For /dev/rsd1i, I get "UNEXPECTED INCONSISTENCY". > > If that's the case, you are probably done! You could mount > your 'a' partition manually on /mnt, look in /mnt/etc/fstab, and > see which letter partitions belong where; use that info to make > sure you have "found" all your partitions. > > BTW, in addition to scan_ffs in base, there is testdisk in ports, > which I think does a better job ATM of finding FFS2 filesystems. > > As mentioned, DO NOT do anything with 'c' partition (be glad, > be very glad, that it didn't find anything resembling a superblock > when fsck'ing 'c'!). It's not a mountable partition but a 'wrapper' > for the whole disk.
Re: how to recover a corrupted disk
On Wed, Dec 01, 2021 at 01:39:39PM +0530, Sandeep Gupta wrote: > Hello, > All partitions except for /dev/rsd1c and /dev/rsd1i are clean. > For /dev/rsd1c , I get "BAD SUPER BLOCK: MAGIC NUMBER WRONG". > For /dev/rsd1i, I get "UNEXPECTED INCONSISTENCY". If that's the case, you are probably done! You could mount your 'a' partition manually on /mnt, look in /mnt/etc/fstab, and see which letter partitions belong where; use that info to make sure you have "found" all your partitions. BTW, in addition to scan_ffs in base, there is testdisk in ports, which I think does a better job ATM of finding FFS2 filesystems. As mentioned, DO NOT do anything with 'c' partition (be glad, be very glad, that it didn't find anything resembling a superblock when fsck'ing 'c'!). It's not a mountable partition but a 'wrapper' for the whole disk.
Re: how to recover a corrupted disk
Sandeep, go ahead reformat your disk. Do keep in mind the structure of a BSD disk though a partition - is usually / b partition - is usually swap c partition - is always the entire disk including a, and b, and it goes on.../var, /usr, /usr/local, /home etc etc Best Regards, -peter On 12/1/21 13:19, Sandeep Gupta wrote: Not sure why not. It seems the rsd1c is where the superblock is. Also there is no other mechanism to refer to the whole disk. I guess it's time to format the disk. On Wed, Dec 1, 2021 at 4:20 PM Janne Johansson wrote: Den ons 1 dec. 2021 kl 11:09 skrev Sandeep Gupta : @Peter, @Janne: Thanks for the infos. Newfs seemed promising but it seems like the disk is beyond repair :(. I did newfs -N and got quite a few location of superblocks: Then I tried fsck_ffs -b #blockid /dev/rsd1c You should *NOT* newfs or fsck against the "C" partition. -- May the most significant bit of your life be positive.
Re: how to recover a corrupted disk
On Wed, Dec 01, 2021 at 05:49:06PM +0530, Sandeep Gupta wrote: > Not sure why not. It seems the rsd1c is where the superblock is. Also Each filesystem has it's own superblock, residing at the start of its partition. c partitions are a way to refer to the whole disk and do not have a filesystems. Writing anything to it will destroy partitions. ATM you likely have a fixable system. After writing to the c partition you will *have* to reinstall. -Otto > there is no other > mechanism to refer to the whole disk. I guess it's time to format the disk. > > On Wed, Dec 1, 2021 at 4:20 PM Janne Johansson wrote: > > > > Den ons 1 dec. 2021 kl 11:09 skrev Sandeep Gupta : > > > @Peter, @Janne: Thanks for the infos. Newfs seemed promising but it > > > seems like the disk is beyond repair :(. > > > I did newfs -N and got quite a few location of superblocks: > > > Then I tried > > > fsck_ffs -b #blockid /dev/rsd1c > > > > You should *NOT* newfs or fsck against the "C" partition. > > > > > > -- > > May the most significant bit of your life be positive. >
Re: how to recover a corrupted disk
Not sure why not. It seems the rsd1c is where the superblock is. Also there is no other mechanism to refer to the whole disk. I guess it's time to format the disk. On Wed, Dec 1, 2021 at 4:20 PM Janne Johansson wrote: > > Den ons 1 dec. 2021 kl 11:09 skrev Sandeep Gupta : > > @Peter, @Janne: Thanks for the infos. Newfs seemed promising but it > > seems like the disk is beyond repair :(. > > I did newfs -N and got quite a few location of superblocks: > > Then I tried > > fsck_ffs -b #blockid /dev/rsd1c > > You should *NOT* newfs or fsck against the "C" partition. > > > -- > May the most significant bit of your life be positive.
Re: how to recover a corrupted disk
Den ons 1 dec. 2021 kl 11:09 skrev Sandeep Gupta : > @Peter, @Janne: Thanks for the infos. Newfs seemed promising but it > seems like the disk is beyond repair :(. > I did newfs -N and got quite a few location of superblocks: > Then I tried > fsck_ffs -b #blockid /dev/rsd1c You should *NOT* newfs or fsck against the "C" partition. -- May the most significant bit of your life be positive.
Re: how to recover a corrupted disk
@Peter, @Janne: Thanks for the infos. Newfs seemed promising but it seems like the disk is beyond repair :(. I did newfs -N and got quite a few location of superblocks: Then I tried fsck_ffs -b #blockid /dev/rsd1c No matter which blockid i tried, it always gave the same BAD SUPER BLOCK: MAGIC NUMBER WRONG. I guess I would have to wipe it clean from here. On Wed, Dec 1, 2021 at 2:06 PM Janne Johansson wrote: > > Den ons 1 dec. 2021 kl 09:12 skrev Sandeep Gupta : > > I am running OpenBSD 7.0 on RPi4. I accidentally removed the usb > > cable connecting the sata ssd to the RPi4. > > Well OpenBSD froze and upon reboot I got the very comforting > > Synchronous Exception message. > > Thankfully, I have another RPi4 running OpenBSD. I can mount the > > corrupted disk ( did the necessary backups). I did fsck on all the > > partitions. > > All partitions except for /dev/rsd1c and /dev/rsd1i are clean. > > For /dev/rsd1c , I get "BAD SUPER BLOCK: MAGIC NUMBER WRONG". > > The "c" partition is not meant to hold filesystems, it is the device > used to talk to "the whole disk" for fdisk and such tools. > > > For /dev/rsd1i, I get "UNEXPECTED INCONSISTENCY". > > If you had any non-bsd filesystems (like a small MSDOS/FAT partition > for booting/firmware/arm blob stuff), it will end up as sdXi (and > j,k,l, and so on if you have more than one foreign fs), so if that is > the case, then it is not unexpected to see FFS' fsck have issues with > FAT filesystems. > > -- > May the most significant bit of your life be positive.
Re: how to recover a corrupted disk
Den ons 1 dec. 2021 kl 09:12 skrev Sandeep Gupta : > I am running OpenBSD 7.0 on RPi4. I accidentally removed the usb > cable connecting the sata ssd to the RPi4. > Well OpenBSD froze and upon reboot I got the very comforting > Synchronous Exception message. > Thankfully, I have another RPi4 running OpenBSD. I can mount the > corrupted disk ( did the necessary backups). I did fsck on all the > partitions. > All partitions except for /dev/rsd1c and /dev/rsd1i are clean. > For /dev/rsd1c , I get "BAD SUPER BLOCK: MAGIC NUMBER WRONG". The "c" partition is not meant to hold filesystems, it is the device used to talk to "the whole disk" for fdisk and such tools. > For /dev/rsd1i, I get "UNEXPECTED INCONSISTENCY". If you had any non-bsd filesystems (like a small MSDOS/FAT partition for booting/firmware/arm blob stuff), it will end up as sdXi (and j,k,l, and so on if you have more than one foreign fs), so if that is the case, then it is not unexpected to see FFS' fsck have issues with FAT filesystems. -- May the most significant bit of your life be positive.
how to recover a corrupted disk
Hello, I am running OpenBSD 7.0 on RPi4. I accidentally removed the usb cable connecting the sata ssd to the RPi4. Well OpenBSD froze and upon reboot I got the very comforting Synchronous Exception message. Thankfully, I have another RPi4 running OpenBSD. I can mount the corrupted disk ( did the necessary backups). I did fsck on all the partitions. All partitions except for /dev/rsd1c and /dev/rsd1i are clean. For /dev/rsd1c , I get "BAD SUPER BLOCK: MAGIC NUMBER WRONG". For /dev/rsd1i, I get "UNEXPECTED INCONSISTENCY". I tried scan_ffs -l sd1 but it didn't report the full disklabel for sd1. What's the least disruptive way out of this quagmire? Or, things are beyond repair and should I wipe clean and start over? Thanks. Sandeep
