Softupdates And Samba

[Michael Powell]

Tim Daneliuk wrote:

> I installed another SATA drive on a FreeBSD 8.1-STABLE box here last
> night. After the disk prep, I mounted it and then shared the whole drive
> via Samba.
> 
> This morning when I came in, the machine had horked all over itself and
> I saw this in the log after the reboot:
> 
> Nov 20 01:06:59 ozzie kernel: ad6: TIMEOUT - WRITE_DMA48 retrying (1 retry
> left) LBA=34066054 3
> Nov 20 01:06:59 ozzie kernel: ad6: FAILURE - WRITE_DMA48
> status=51<READY,DSC,ERROR> error=10< NID_NOT_FOUND> LBA=340660543
> Nov 20 01:06:59 ozzie kernel:
> g_vfs_done():ad6s1d[WRITE(offset=174418165760, length=131072)]e rror = 5
> Nov 20 02:15:07 ozzie kernel: ad6: TIMEOUT - WRITE_DMA48 retrying (1 retry
> left) LBA=14580695 35
> Nov 20 02:15:07 ozzie kernel: ad6: FAILURE - WRITE_DMA48
> status=51<READY,DSC,ERROR> error=10< NID_NOT_FOUND> LBA=1458069535
> Nov 20 02:15:07 ozzie kernel:
> g_vfs_done():ad6s1d[WRITE(offset=746531569664, length=131072)]e rror = 5
> 
> 
> I reformatted and remounted the drive and accidentally forgot to enable
> softupdates.  It seems to now be working fine.
> 
> Is there a known interaction with softupdates and Samba such that I should
> not use them in this case, or could this just have been a loose cable
> or something?  The drive is pretty new (< 6mo) and it's never been a
> problem when I used it on an NTFS system previously.
> 
> TIA,

I can't speak to -Stable, as I bounce from -Release to -Release. But I have 
used Samba with softupdates for years and never experienced any problem 
which might be related to such a combination.

While it exists the possibility of flaky controller/driver bug I would look 
towards a hardware situation first. First thing I'd do is get a bootable CD 
with the drive manufacturer's diagnostics on it. Western Digital has a 
bootable .iso you can download if it happens to be a WD. Do the destructive 
write all zeros comprehensive test and look for any errors, particularly 
surface defects. I do this with any used drive before using it again.

Oh yeah - swap in a new cable first. Plug it in and out several times to 
scratch through any thin film layer of corrosion which may have formed on 
the copper.

RAID controller and a so-called "Green" drive? They are very prone to 
falling "offline", as per:

http://wdc.custhelp.com/cgi-bin/wdc.cfg/php/enduser/std_adp.php?p_faqid=1397

Most of the time you can get away with running a desktop drive on a RAID 
controller and not have problems, but the potential exists. In lieu of this, 
you could also install smartmontools and look at the drive with various 
smartctl tests. I take numbers from smart testing with a grain of salt. I 
generally see them as an additional data point rather than trying to split 
hairs into a conclusion. The thing you would be trying to discern here is if 
the bad sector remap area has filled. When this happens the drive can no 
longer "hide" bad sectors from the OS.

I'd bet it's something simple like a bad cable. Also recall the first rule 
of maintenance: "If it works, don't Fix It!"  :-)

-Mike