What is the best way to do a standard standalone image backup of the
system disk on these units that is supported as a boot device in case
of emergency?
AFAIK disk, and supported tape drives. Disk to disk is about the
fastest way you can go. Tape is a little easier to send off site if you
send backups off site.
Tape is "high maintenance"! Or, at least, DEC/Compaq/H-P tape devices
have, in my experience, been high maintenance devices!!
Yes, if you want it to be supported and guaranteed to work. In
practice, it will probably be OK if there is essentially no activity on
the system, other than the basic stuff.
If you can't shut down your system, you are doing something wrong. If
it's not doing important stuff, shut it down, boot it from CD, DVD or a
disk copy of one of those, go into the DCL $$$ menu and make a
disk-to-disk backup. If it is doing important stuff, consider that
reboots might be necessary for patches etc, so you really need a cluster
with more than one system disk so that the cluster can stay up even when
one machine is rebooted.
A faster way would be to have the system disk shadowed (which you should
do anyway), shut down, remove one member then reboot. This saves you
the time needed to do the disk-to-disk backup, and the one member you
remove is an exact copy of the quiescent disk.
You don't HAVE TO do a standalone boot. It is the most certain way to
get a good backup. If you backup a running system, files that were open
for write may exhibit problems when they are restored. Maybe you can
live with it. I would prefer not to have to!
There are various strategies you can use to minimize down time. One is
to mirror your disks. You shut down, break your mirror sets, and
reboot. Make your backup disk to disk or disk to tape from the offline
member of the mirror set. Resilver your mirror set. It's not totally
satisfactory but it's about the best you can do.
kczwei,
For small systems, the best solution for fast recovery may very well
be disk-to-disk.
Of course, open files can be an issue. The important question is:
Which open files?
The Gold standard is a standalone backup. Can one use a backup of a
running OpenVMS system? Of course. However, there are dangers.
Changes to the open (and active) SYSUAF may not be on the backup.
Queue file entries may be a problem. Active database and indexed files
can be an issue.
If you have host-based volume shadowing, disconnecting a shadow set
member from a momentarily quiesced system is an option. The
disconnected member can be remounted (read-only) privately and then
imaged to other media.
The true answer is to do a review of the system and files, and ensure
that all issues are accounted for.
As a final note, avoid the use of /IGNORE=NOINTERLOCK. This suppresses
the warning messages, but does little to truly help you with the
problem of getting a good backup.
Lastly, if analyzing the system is a challenge, consider an outside
audit (Disclosure: We provide such services). Having recovered systems
from problems, it is far better to do the analysis upfront than it is
after a crisis has already started.
- Bob Gezelter, http://www.rlgsc.com
OTOH, that "high maintenance" tape is far more likely to survive been dropped
onto the computer room or office floor.
IMHO, hard drives are too fragile, with too many ways to fail, to be trusted
as the only backup medium in a backup procedure.
Simon.
--
Simon Clubley, clubley@remove_me.eisner.decus.org-Earth.UFP
Microsoft: Bringing you 1980s technology to a 21st century world
Either:
1) shutdown and use standalone backup (or it's non-VAX replacement)
2) shadow the system disk
or
3) risk loosing some data
On my systems I can identify what data is at issue and procede
accrdingly. I do not agree with the concept that the system disk does
not need to be backed up regularly. There are lots of files that are
being written to during normal system operations. Some of these can
be moved off the system disk.
When I'm doing system management, I don't believe in ever loosing a byte
of someone else's data. That includes thier password (which is on the
system disk unless you move it), et. al.
I also don't believe that I should have to re-install products or
patches after a disk failure. I just restore a recent copy of the
system disk.
I've never dropped a *tape drive* onto the floor! I don't recall ever
dropping a tape cartridge.
I've been tempted to drop both tape and drive into the garbage!
$$$ MOUNT /OVER=ID DDCUnnnn:
$$$ set bootblock/i64 DDCUnnnn:
Next run BOOT_OPTIONS to validate the boot options against the system disk
$$$ @sys$manager:boot_options