Re: GPT missing after controller swap (wd to ld)

[christos%zoulas.com@localhost (Christos Zoulas)]

On Oct 10, 11:35am, louis%zabrico.com@localhost (Louis Guillaume) wrote:
-- Subject: Re: GPT missing after controller swap (wd to ld)

| On 10/10/16 8:14 AM, Christos Zoulas wrote:
| > In article <4c31b2ab-3161-9dc1-2d2b-74278c891065%zabrico.com@localhost>,
| > Louis Guillaume  <louis%zabrico.com@localhost> wrote:
| >> Hi,
| >>
| >> On NetBSD 7.0_STABLE, i386, (from earlier this year) I had configured a
| >> couple of disks with GPTs and then switched controllers (wd1 now shows
| >> up as ld1) and now the GPT appears to have gone missing. However my
| >> wedges are still there...
| >>
| >> # gpt show ld1
| >> gpt: error: map entry doesn't fit media
| >> gpt: unable to open device 'rld1d': No such file or directory
| >>
| >> # dkctl ld1 listwedges
| >> /dev/rld1d: 2 wedges:
| >> dk0: boot0, 524288 blocks at 128, type: ffs
| >> dk1: disk0, 3906504704 blocks at 524416, type: raidframe
| >>
| >> The first wedge is intended to just hold a kernel and emergency root
| >> file system for booting. The root file system is on a raid array built
| >> with dk1 (and others). I'm currently booted off a separate disk because
| >> the bootmenu did not include the boot.cfg "installboot"-ed to ld1.
| >>
| >> Did something in the BIOS overwrite the GPT? How to recover?
| >
| > Can you try gpt show /dev/rld1d? Also show your dmesg?
| >
| > christos
| >
| >
| 
| 
| Hi Christos,
| 
| The gpt output is similar but not identical...
| 
| # gpt show /dev/rld1d
| gpt: error: map entry doesn't fit media
| gpt: unable to open device 'rld1d': Undefined error: 0
| 
| Also /dev/dk3 will not reconstruct on the raid (raidctl -R /dev/dk3 
| raid0), leaving these messages...
| 
| raid0: initiating in-place reconstruction on column 1
| raid0: IO failed after 5 retries.
| raid0: IO failed after 5 retries.
| raid0: Recon read failed: 22
| raid0: reconstruction failed.
| 
| But no low-level (ld or twa) IO messages.
| 
| At this point I'm thinking of this procedure for recovery...
| 
|     o Wipe ld2 and re-partition
|     o Rebuild a new raid on ld2 (which has dk3)
|     o Copy everything over
|     o Boot from the new raid disk
|     o Wipe ld1
|     o Rebuild the raid with the new ld1
| 
| Relevant parts of the dmesg.boot are below. Thanks for looking!

Before you do anything, can you please rebuild the gpt binary from
HEAD and see what that prints?

christos