(Question at bottom)
I upgraded a remote NW6.5sp4a server on the weekend (was having no
problems with it but did not realize it was on such an old service pack)
Server was 6.5SP4a - 5.70.04
DS - 10552.79
NSS - 3.23-2
All NSS volumes, no traditional anywhere
Pools: SYS, DATA
SYS Pool Volume: SYS 8GB Total Size - 5GB Free 36MB purgable

The server had transactions enabled on SYS which I disabled before the
I did a unattended DSREPAIR which was clean
Installed SP8, iprntnw65sp8a,and TCPIP--NW65SP8 then rebooted server.

Server came back up and was basically fully booted and then went into
the debugger.
I downed the server from the debugger and restarted at which time it did
complete the load.
From here my PRODUCTS.DAT file was hosed but I copied in one from
another SP 8 server and rebooted again. Everything seemed to come up
fine and I could see items in the PRODUCTS.DAT again.

I then installed edir87310_ftf2 and rebooted
then installed N65NSS8b and rebooted.
At this time I did another unattended DSREPAIR which was clean
I did a full purge on all volumes from a workstation.

Things were fine but when I checked it on Monday morning the logger
screen was showing the following error (BackupExec running backup when
it was logged)
1:39:04 am NSS<COMN>-3.27b-714: zasAuthModel.c[2057]
Error removing visibility for trustees just removed

I was then of the thought that I would need to do a
nss /visibilityrebuild this coming weekend to fix this error.

In the meantime I decided to run CHECKVIS.NLM /SYS to see what it would
return. I was led to believe that this would have minimal impact to
users but it rendered the server unavailable. I could ping it and it
would respond and I could move between console screens but that was it.
We ended up trying to down the server through the alternate console
which did not work. I then downed it through the debugger and restarted it.

When loading it came back with the following errors on the console

Loading volume "SYS"
Activating volume "SYS"...
** Volume layout v36.03
** Volume creation layout v36.03
** Processing volume purge log
** ......Error fixing visibility of trustees that were being added or
removed when the system crashed

Still have the error showing up when the backup runs
Mar 11, 2010 1:39:04 am NSS<COMN>-3.27b-714: zasAuthModel.c[2057]

Error removing visibility for trustees just removed

Is it normal for the CHECKVIS to render the server unavailable?
How long should the CHECKVIS take on and 8GB volume (15K 320SCSI Mirror)

How should I fix this? Should I just run a POOLREBUILD /PURGE on SYS
and then the other pools? NSS /VISIBILITYREBUILD as well?

Thank you for any assistance you can offer!