xfs_force_shutdown

[Hieu Le Trung]

Eric Sandeen wrote:
> Hieu Le Trung wrote:
> > Hi,
> >
> > What may cause metadata becomes bad? I got xfs_force_shutdown with
0x2
> > parameter.
> 
> Software bugs or hardware problems.  If you provide the actual kernel
> message we can offer more info on what xfs saw and why it shut down.

I'm not sure which one is it but the issue is hard to reproduce. 
I have following in the dmesg but I'm not sure it's the right one
  <1>I/O error in filesystem ("sda2") meta-data dev sda2 block 0xf054f4
("xlog_iodone") error 5 buf count 32768
  <5>xfs_force_shutdown(sda2,0x2) called from line 956 of file
fs/xfs/xfs_log.c.  Return address = 0x801288d8

Furthermore, the driver's write cache is
  <5>SCSI device sda: drive cache: write back

The xfs_logprint shows 'Bad log record header'
xfs_logprint: /dev/sda2 contains a mounted and writable filesystem
    data device: 0x802
    log device: 0x802 daddr: 15735648 length: 20480

Header 0xa4 wanted 0xfeedbabe
**********************************************************************
* ERROR: header cycle=164         block=14634                        *
**********************************************************************
Bad log record header

So I wonder what may cause bad record header?

> 
> > How can I analyze the metadata dump file?
> 
> the metadump file is just the metadata skeleton of the filesystem; you
> can mount it, repair it, point xfs_db at it to debug it, etc.

Is there any tutorials or guideline in using xfs_db to debug the issue?

> 
> -Eric
> 

Thanks,
-Hieu