Dumping Images of my VAX-11/730's Drives?

Peter Coghlan cctalk at beyondthepale.ie
Tue Mar 8 17:21:51 CST 2016

> I want to get raw images of the system's drives off the machine and onto my
> modern systems. I can think of several approaches, and still more approaches
> have already been suggested in that VCF thread. I have a number of questions,
> and I'm also keeping my eyes open for hardware that might help me out. I'm not
> presently talking to eBay, so that limits my options.
> First of all, if I manage to get TCP/IP networking up and running today, is
> there some way under VMS for me to dump raw disk blocks over the network to
> one of my UNIX-like systems? Alternately, if I manage to cobble together a
> Linux box running an older DECNET-aware distribution and bring up DECNET on
> the VAX, would that give me a way to dump raw disk blocks to a file on it
> across the network? I'm still quite clumsy under VMS. One of these
> network-based approaches seem like the only options that I would have any
> chance of achieving today, assuming that the networking hardware on my 11/730
> is even in working order.

Savesets produced using VMS BACKUP are the ideal way to archive your VMS system.
They will save everything you need in a format which can be restored onto any
disk big enough to hold the data, selectively if necessary, while dealing with
any errors on the input or output media.  BACKUP can be run standalone or under

If you get TCP/IP networking like Multinet (ie not like CMUIP) running, you
should be able to use FTP, rcp or maybe even TFTP to move a VMS BACKUP saveset
to another system.  The snag is you need enough scratch space to create the
saveset on the 11/730 before you transfer it.

> I don't think I have the patience to dump an R80 drive across an async serial
> port, but if I did have the patience, is there some way to accomplish this
> under a stock VMS 5.2/7.3 installation? Ditto for the RL02 and 9-track tapes.

C-Kermit for VMS might be able to do this - I can't recall.

If you mount /foreign your non-system disk, it should be accessible at a logical
block level instead of at a file level.  VMS BACKUP won't like this but COPY
should just copy logical blocks from the foreign mounted device.  This probably
isn't very useful to you but rcp or FTP PUT might also similarly cope with a
foreign mounted devices and this may be another way of generating a raw dump
of the device, provided there are no errors on it.  (There may be issues
detecting the size of the device and the operation may end with an error when
no more blocks can be read.  If whatever software you use doesn't try to
discard it's output on encountering an error, all should be well.)  However,
you can't mount your system disk /foreign.

Another way would be to write some code (VAX MACRO assembly / C / FORTRAN /
BASIC or whatever compiler you have to use VMS system services like SYS$ASSIGN
and SYS$QIO to read logical blocks from the disks and do something sensible
when errors are encountered.  This might involve a steep learning curve and the
results will probably not be as well optimised to the task as VMS BACKUP.  It
should be possible to find some sample code to do something like this.

> * It was suggested that I might be able to cluster the 11/730 with a MicroVAX,
> and then transfer data onto some SCSI device on the MicroVAX such as a
> SCSI2SD.  I think I'd need to find a fairly turnkey MicroVAX, though, to
> avoid a bring-up problem that's even bigger than the data transfer problem
> I'm trying to solve.

Clustering is pretty simple when you know how but if you don't want to get into
configuring a cluster, a DECnet connected system or emulated system would
probably be the way to go.  Configuring DECnet on VMS can be done very easily
with surprisingly little understanding of what is going on and is less invasive
than configuring a cluster.

On VMS, any file, including a BACKUP saveset can be specified as being located
on a remote DECnet node, so it is possible to run BACKUP on your 11/730 and have
the output saveset situated on a different VAX / Alpha / Itanium / emulated
system running VMS or on a unix or other system capable of running DECnet well,
(ultrix?), even a PC/Macintosh running DOS/Windows/Macos and DEC Pathworks.

If your 11/730 is already configured to be a cluster member (if it says
something like "Waiting to form or join a VAXcluster" on the console at boot
time and then pauses for while before continuing) then you probably don't have
to do anything further to it to make it function as part of a cluster.  The
only experimentation required would be on the additional cluster member, which
could be an emulated system using simh for example if you don't have any other
suitable hardware available.  Once you are clustered, you can access disks on
a remote cluster node as if they were local.  Clustering with an emulated
system would be especially suitable for producing raw block copies of the
disks on the 11/730 on the filesystem of the system hosting the emulation.

Peter Coghlan.

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