VAXstation 4000 VLC disk size limit? (414 Views)
Occasional Advisor
Posts: 9
Registered: ‎07-06-2012
Message 1 of 5 (414 Views)

VAXstation 4000 VLC disk size limit?

I have tried three disks so far.


For the 1GB drive the size is shown correctly in firmware.


For one 4GB drive i see the drive multiple times in firmware at different SCSI IDs. I could format the drive but i still see it multiple times.


For the other 4GB drive i see the drive only one time in fimware with the expected SCSI ID. But the size shown is wrong (42MB insted of 4GB). The wrong size does not change after formatting.


Does some disk size limit apply to the machine or may some drives be defective (i could try to check the drives using another machine/OS)?





Respected Contributor
Posts: 315
Registered: ‎05-01-2003
Message 2 of 5 (406 Views)

Re: VAXstation 4000 VLC disk size limit?

Like your other question...  A lot depends in the Brand and type drive you're trying to connect to the VLC.  Most of the earlier VAXstation 3100s had the size limitation just barely above 1GB (1.073 or so) but the VLC wasn't burdened by this restriction in capacity.  The sizes you've mentioned that you tried should work fine but I'd definitely check them on another O/S or system before discarding them.


The "seeing multiple drives" problem almost sounds like you've got multiple units using the same SCSI address.  I've seen many situations where that happened BUT I've also seem the same symptom for a drive that isn't working correctly.  I'd check the documentation for that drive carefully to see if there are multiple jumpers to set the SCSI address because you can't really tell when you get eight DK devices which one is really real.  The drive that shows 42MB?  There are some drives that do have special jumpers to limit size for special configurations but I haven't seen any that intentionally make a drive that much smaller.  Since you've already formatted the disk it might be interesting to try to write to the drive and boot from it (when you get a working CD) and see if VMS thinks the drive is 4GB.  Again, like with your CD writer, most DEC VAXstations tended to work better with DEC-branded disks but by the time the VLC came out some of that preference was starting to loosen up a bit.  Many older SCSI drives could "adjust" themselves to work with older "slower" flavors of SCSI but there are/were limitations.



Honored Contributor
Posts: 9,182
Registered: ‎02-23-2005
Message 3 of 5 (394 Views)

Re: VAXstation 4000 VLC disk size limit?

Honored Contributor
Posts: 3,009
Registered: ‎07-31-2003
Message 4 of 5 (370 Views)

Re: VAXstation 4000 VLC disk size limit?



   Until you've got the machine at least booting an OS, I'd recommend sticking with the "correct" vintage disk drives. Remember, none of the Ss in SCSI stand for "standard". For CD drives RRD42, for disks RZ26, RZ28 or(maybe) RZ29. 1GB is more than enough to install OpenVMS, plenty of layered products and still have enough left over for a decent sized page file. (indeed, I once configured a VAXstation3100 with a cut down V6.2 using only 24MB of disk space - it booted from cold in 52 seconds)


  Make sure you know the SCSI ID of the CPU, and you avoid duplicating it (a common symptom when you do is seeing multiple instances. Also make sure you know if the drives you're using have terminators.

A crucible of informative mistakes
Occasional Advisor
Posts: 9
Registered: ‎07-06-2012
Message 5 of 5 (303 Views)

Re: VAXstation 4000 VLC disk size limit?

VMS shows the expected disk size and seems to work reliable.


The same applies to BSD 5.1.


So 4.3GB should be ok on that machine.


The opinions expressed above are the personal opinions of the authors, not of HP. By using this site, you accept the Terms of Use and Rules of Participation.