Re: PR 59570 - tar fails with physical tape drives - root cause likely found ?

On Wed, May 06, 2026 at 11:27:01AM -0400, vom513 wrote:
> 
> I had posted about this a while ago.  In short - writing to a real SCSI tape drive on recent/release NetBSD works.  Reading the archive back always results in tar header errors (regardless of blocksize etc).
> 

Sorry, I am not seeing this problem with my set up here, I have:

 uname -a
NetBSD siren 10.99.12 NetBSD 10.99.12 (SIREN) #0: Tue Dec  3 15:23:12
ACDT 2024  toor@siren:/usr/src/sys/arch/amd64/compile/SIREN amd64

(yes, old but in the timeframe you state)

ahc0 at pci5 dev 1 function 0: Adaptec 29160 Ultra160 SCSI adapter

and

scsibus0 at ahc0: 16 targets, 8 luns per target
scsibus0: waiting 2 seconds for devices to settle...
st0 at scsibus0 target 4 lun 0: <HP, Ultrium 4-SCSI, W51D> tape removable

I have a tar archive written by this kernel and it is readable:

gtar tvf /dev/rst0v
drwxr-xr-x root/wheel        0 2022-06-13 15:32 ./
drwxrwxrwx root/wheel        0 2025-06-04 16:11 ./Multimedia/
drwxrwxrwx root/wheel        0 2025-11-19 15:10 ./Multimedia/@Recycle/
-rwxrwxrwx root/wheel       78 2025-11-19 15:10 ./Multimedia/@Recycle/desktop.ini

I have also restored files from backups using dump without an issue.

Can you please provide information about what scsi adaptor and tape
drive you are using?

-- 
Brett Lymn
--
Sent from my NetBSD device.

"We are were wolves",
"You mean werewolves?",
"No we were wolves, now we are something else entirely",
"Oh"