SUMMARY: network backup software

From: Joe Van Andel (
Date: Fri Oct 05 1990 - 17:04:58 CDT

I asked sun-nets for advice on network backup software, to meet the following

1 Automated, unattended, simple to use package
2. Package can backup a running workstation, w/o going single user
3. Maintains a logfile such that I can locate what tape contains a given file.
4. Flexible backup policy, including the ability to include/exclude given
directories. (How many copies of the X11 binaries do I need on tape, after


Here is a summary of what I found. (Sorry for the delay in posting this).
I've quoted freely from many of the people who responded.

Free software:
1) supersaver,
available from ( in unix/ss.tar.Z
From the README:

        Super-saver is a backup/restore program that allows a machine with an
        exabyte tape drive to be a backup server for a network of machines.
        The code accesses all files through normal unix system calls, and can
        therefore be used without shutting down machines or limiting disk
        activity. Fast algorithms are used where possible to increase backup

2) 8mmbackup,
available from ( in pub/8mmbackup.shar.Z

From the README:
The system is essentially an elaborate frontend for creating cpio
archives on a high-capacity tape device, managing scheduled backup
cycles consisting of an exhaustive ('full') backup followed by
numerous 'incrementals', which include just those files that have been
modified or created since the prior backup run. The configurer
designates what directory hierarchies in the file system to save and
what parts to prune from those directory hierarchies. Comprehensive
online audit tracing and registration of preserved files is
maintained, as well as tape-capacity monitoring and broad operational
error checking and recovery, to ensure that minimal operator
intervention does not mean missed and neglected problems.

This script does not explicitly deal with backing up machines over a network.

3) Configure a solution using available Sun tools:
Easy -- have the machine with the exabyte in the other's /.rhosts, and
have cron run a script at night that rsh's an rdump to each machine.
Sun's 4.1 dump has the ability to just dump a listed set of files/directories.

Of course, as the backup load grows, you have to deal with how many dumps fit
on a single tape, and compute the correct dump parameters to avoid trying to
write past the end of the tape.

One person's solution:
I do level 0 dumps of each of my workstations on about a monthly
schedule, and level 1 dumps of all of them every night under cron, to a
remote exabyte. I've never bothered to go single-user before dumping
at any level, and have had no problems restoring files or entire file

Some more ideas on automatically dumping a machine:
 1) get cron to create a file (/etc/dodump) and reboot the machine
 2) In rc.local (after ifconfig) do your dump. At this stage there
    will be no activity.

Another comment re this sort of solution:
  This is pretty awkward since `[r]dump' doesn't have an
option to run in the background and return an exit status for
different error conditions.

You may have to check the return code from fsck to be safe.

Software from vendors:
1. Legato Networker. 415-325-2200
This is a fairly new package. The first release created index files that
required 5-10% of the file space dumped. Legato claims that this has been
reduced to ~2-3% in a new release.

1 Happy customer
1 Not-so-happy customer, because of the size of the index files.

2. BACKUP.UNET from Unitech Software. 703-264-3301 fax 703-264-7796
They claim:
        Centralized backup from any system in the network.
        Share tape drive devices and media management (allows one tape
                drive to be used for backup and restore for all hosts).
        Optional data verification.
        Users can locate and restore their own files locally or remotely.
        Automatic media management (multiple systems/volumes onto one tape).
        Full and incremental backup.
        Data encryption across network.
        Audit trails for each system and a network summary.

3. BUDTool from Delta Microsystems
        5039 Preston Ave
        Livermore, CA 94550

Available from their distributor:
Peripheral Devices Corp. (215)-640-0446
Philadelphia, attn: Mike Fanelli

Two persons said they were satisfied customers.

4. REELbackup from Sceptre
P.O. Box 8031
Ann Arbor, MI 48107

        Phone: (415)449-6881, Fax: (415)449-6885

One satisfied customer with ~40 diskfull workstations and a couple of 4gb servers).


Product uses dump,rdump and writes an index block at the start of tape.
This product doesn't currently provide a database of files dumped.

6. from Unitech

Other observations and comments:
1) Lots of folks say they use dump while running multi-user, but in the middle
of the night, when things are quiet.

2) Clearly any package must run on a quiet file system to avoid problems with
backing up a directory that has been moved between the 'scan' pass and the
'dump' pass. If an inode which used to be a file becomes a
directory, or vice-versa, in between the mapping pass and the dumping
pass, the *entire dump* can become unreadable by restore.

3) It's important to differentiate "disaster recovery" from
"archival" when evaluating backup products. It's hard not to laugh
when people ask me if I can retrieve a file from a 5-year-old backup
tape. I can point them at a mostly-disorganized pile of magtapes and
wish them luck. In other words, our current backup scheme is only
meant for disaster recovery. Since I've been here (about 2 years),
I've explained this to our users and suggested they make `tar'
archives of work they want to save offline rather than relying on
being able to locate it from dump/cpio tapes.

4) One user mentioned that running Legato's network consumed 100% of his
3/60-8 CPU, so he wouldn't want to run it during the day!

I have not yet had the chance to demo any of these packages yet. When I do,
I'll post my results.

Once again, thanks for your help!

        Joe VanAndel
        NCAR - ATD/RSF
        P.O Box 3000 Fax: 303-497-2044
        Boulder, CO 80307-3000 Voice: 303-497-2071

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