[plug] Sun gurus? Question re DiskSuite

[Ian Kent]

On Fri, 23 Jun 2006, Denis Brown wrote:

I haven't done much with DiskSuite for years but I'll try.

> Dear PLUG list members,
> 
> Colleague has Sun DiskSuite in a system with hardware RAID1 system drives and
> four disks in hardware RAID5.   One of the system disks failed and he rebooted
> from the system mirror disk.

If it's hardware RAID you shouldn't need to boot from a mirror.
Are you sure this isn't software RAID?

If it is software RAID and he might have booted from the system device 
device file instead of the DiskSuite device file then it won't see the 
replica db.

> 
> But when attempting to mount the RAID5 array or do anything with the DiskSuite
> commands he gets consistently the error message  "there are no existing
> databases"

Don't think you can do much without a replica db.

> 
> Some surfing shows that a recommended approach is to have replicadb's
> scattered over several disks to prevent loss of volume information.
> Colleague did not set up the system, original sysadmin parachuted-in-over (tm)
> and gone.   Perhaps the replicadb's exist on the system drive, but how to
> access them, if that is what's needed??

I seem to remember you  need at least three and at least two must be 
available (I think).

> 
> Backups exists but would be nice if he could rescue the RAID5 with minimal
> pain.
> 
> Any suggestions appreciated!

Get the system disk back under DiskSuite control.
Maybe it's not to late to boot from the correct device in which case 
everything should just come back.

You should be able to re-create and initialize the mirror with only one 
of the mirror devices by adjusting the DiskSuite config.

Then you have the problem of adding the RAID5 back so that they can be 
seen again.

He really must call Sun support, they will be able to talk him through it.

Ian