Third party disks for VS3100 (Ultrix) - was: Ultrix 3.1 trashes root partition

[Franz Haberhauer]

In article <1236 at ifi.informatik.uni-stuttgart.de> I wrote:
>
>We have problems with mysteriously damaged filesystems, too.
>We have got a VS3100 with a local MAXTOR 8760S SCSI-disk serving another
>diskless VS3100 
>During multiuser boot the following error messages were logged (repeated
>several times):
>
>MESSAGE    SCSI 1 regs: 80=0 84=0 88=20 8c=0 90=0 
>           _94=8 adr=400 cnt=0 dir=1 
> 
>MESSAGE    szintr: (bus=1) stray interrupt - no 
>           _disconnected targets 
>
These messages are observed always when a mount is performed (Ultrix V3.1).

>Though, as long as only the server is running everything is fine, but after 
>the client has been booted a few (~2-3) times the server crashes and fsck 
>reports severe problems with partially unallocated inodes and inodes with 
>spare fields containing values (once in the root file system and after 
>reinstallation in the /usr-filesystem).
We tried to install Ultrix V3.0, but the system survied only a little longer.
Yet the messages above are accompanied by a third one (SI1) which is
also written to the console. 

DEC technical support then told me, that this third party disk (on the
external SCSI bus) would only work correctly with a VS3100 serving
other diskless VS3100, if there is a DEC supplied SCSI disk on the
internal SCSI bus (very strange??? - I haven't tried it yet). 
There seems to be a relateted problem with VAX-clusters under VMS.

Another point is that the MAXTOR XT-8760S is listed in 
/sys/data/scsi_data.c on a DS2100 whereas it is missing on a VS3100.

Any help, pointers, etc. appreciated.

Franz                   haberhau at ipvr.informatik.uni-stuttgart.dbp.de
                        haberhau at informatik.uni-stuttgart.de