SUMMARY: Solaris 8, dumpadm, panic() and sync timeouts to mirrored swap

Thanks to all those who responded.

The best answer I got was to use DiskSuite to mirror swap or root
disks, and you can dump to a metadevice.

-- 
Greg Gallagher
Sr. UNIX Systems Administrator
First Options Chicago .... (312) 362-3643


On Wed, Apr 03, 2002 at 11:01:00AM -0600, Greg Gallagher wrote:
>    I recently had a problem on a SunFire E3800 running Solaris 2.8,
> where I lost an entire IO Boat (i.e. the PCI IO controller and all
> fiber and QFE cards on that boat).
> 
>    I have Veritas encapsulated disks which are mirrored across
> controllers:
> 
>    c1t0d0 - primary
>    c0t0d0 - mirror
> 
>    My swapdevice, which is currently a Veritas encapsulated volume,
> cannot be used to dump to, according to Sun because if the system
> panics or has a Volume Manager problem dumping to swap isn't going to
> help me.  Sun suggested having a dedicated swap device, if we wanted
> to have Veritas Encapsulated mirrored swap.
> 
>    The problem that I see with this is what happened to me yesterday.
> Dumpadm was configured like so:
> 
> excalibur:/root# dumpadm
>       Dump content: kernel pages
>        Dump device: /dev/dsk/c0t0d0s1 (dedicated)
> Savecore directory: /var/crash/excalibur
>   Savecore enabled: yes
> 
>    This slice is one side of the swap mirror.  However, swap is
> configured like this:
> 
> excalibur:/root# swap -l
> swapfile             dev  swaplo blocks   free
> /dev/vx/dsk/swapvol 229,8      16 16383600 16383600
> 
>    If I tell dumpadm to use swap, it refuses:
> 
> excalibur:/root# dumpadm -d swap
> dumpadm: no swap devices could be configured as the dump device
> 
>    Now what happens if /dev/dsk/c0t0d0s1 is inaccessible?  Here's what
> I saw on the panic():
> 
> syncing file systems...
> panic[cpu8]/thread=2a100091d40: panic sync timeout
> dumping to /dev/dsk/c0t0d0s1, offset 65536
>   0% done: 0 pages dumped, compression ratio 0.00, dump failed: error 5
> 
>    Sure, when the system comes back up I can reset the dump device to
> be the other side of the swap mirror, c1t0d0s1... but I've lost the
> data from the panic.
> 
>    So my REAL question is this: How can I configure everything so I
> have a fault tolerant dump device?  Is it possible?
> 
> Thanks in advance, I'll summarize,
> 
> -- 
> Greg Gallagher
> Sr. UNIX Systems Administrator
> First Options Chicago .... (312) 362-3643
> _______________________________________________
> sunmanagers mailing list
> sunmanagers@sunmanagers.org
> http://www.sunmanagers.org/mailman/listinfo/sunmanagers
_______________________________________________
sunmanagers mailing list
sunmanagers@sunmanagers.org
http://www.sunmanagers.org/mailman/listinfo/sunmanagers