[Simh] VMS: Really big files?

[Kevin Handy]

Zachary Kline wrote:

> Hello,
>     Today when I got home today, in addition to the odd cracker trying 
> to get into my FTP server, I found the following message on my virtual 
> VMS console:
> %qman-i-freedisk, free up 354,096 blocks on zkvax::dua0.  (that's my 
> system disk.)
>     I've tried cleaning up the security audit log, purging all sorts 
> of files, and still haven't found the apparently one very large file 
> taking up so much space...Are there any tips on what this might be?  I 
> could swear that yesterday I had plenty of space.  Of course, since 
> then I did install TCPware, so who knows...
> Sorry for this message.  I know I'm supposed to find answers to 
> questions like this in the docs, but it's proving rather complicated 
> sometimes...
> Thanks,
> Zack.
>  

What you're seeing is VMS being concerned about low free
disk space on the system disk. It will have put many programs
to sleep until some free space is created, to keep the problem
from becoming even worse. I don't usually see it complaining
with a number that high though.

If you are sure it is a simgle large file taking over, you can
look for it using a command like

    dir dua0:[000000...]/sis/sel=siz=min=1000

which will search the dka0 drive for files larger than 1000
blocks. Adjust as necessary.

If you know what you are doing, you may also want to try a

    purge/lo dua0:[000000...]

to purge off all backup versions. This can often remove a lot of log
files, but if you are doing funny things with versions, it may not
be what you want to do.

Another possibility, is lost files.

    anal/disk/repair dua0:

will try to search out and repair such problems. Old versions of
dcltables, and swap files. often get lost after updates. This command
can  sometimes go horribly wrong if your free block map is bad.
You really want to have a backup before you try this. You should run
this command several times until it no longer fixes anything.

Nevertheless, you should understand what each command is
doing before trying them. The manuals, and the 'help' command
are your friend here. These commands need to be modified for
the type of disk you have, etc. It is a very good idea to make
backups before doing something you don't understand completely.
(Zip up your emulated drives before playing)