Re: Please critique my backup practices

On Thu, 20 Mar 2008 12:36:19 -0700 (PDT), tadamsmar <tadamsmar@xxxxxxxxx> wrote:
On Mar 20, 2:36?pm, Dale Dellutri <ddelQQQl...@xxxxxxxxxxxx> wrote:
On Thu, 20 Mar 2008 07:02:14 -0700 (PDT), tadamsmar <tadams...@xxxxxxxxx> wrote:
To do a backup, I pop a drive out of a shadowset, back it up and put
it back.

I assume you're talking about VMS Volume Shadowing. ?As far as I know,
taking a drive out of a shadowset causes the drive to look the same as
if there'd been a power failure. ?In other words, it does not properly
close open files.

I assume that you take image backups. ?If so, there's no benefit to
taking the drive out of the shadowset to take the image backup.
According to service techs that I talked to when I first set up
volume shadowing, there's no advantage over taking an image backup
of the volume set (the DSA device).

I assume that this is still true.

The problem is, I don't record the backup dates.

You could record backup dates if you simply took an image backup
of the volume set.

Don't I have to shutdown my system to do that?

I finally found the relevant item in "HP Volume Shadowing for
OpenVMS", v7.3-2. Chapter 7, Section titled "Data Consistency
Requirements": "Removal of a shadow set member results in what
is called a crash-consistent copy. That is, the copy of the
data on the removed member is of the same level of consistency
as what would result if the system had failed at that instant."
(pg 124 in my copy).

Actually, reading the entire section titled "Guidelines for
for Using a Shadow Member for Backup" would be very useful.


I have a incremental that runs every night that does record backup
dates.
If I had to restore, I would apply the last image and all the
incrementals after it. ?But I guess I would get some extra files.
This is easy, I never have to shutdown, but what are the gotchas?
Note that if I am *planning* to do a restore I don't use incrementals,
I just use a fresh image backup.
I have never had to do an emergency image restore using incrementals.

I'm not an expert, so what I've said above may be wrong. ?You should
check this backup scheme with the service techs (I assume you have
a support contract).


--
Dale Dellutri <ddelQQQlutr@xxxxxxxxxxxx> (lose the Q's)
.

Relevant Pages

  • Re: Please critique my backup practices
    ... I assume you're talking about VMS Volume Shadowing. ... taking the drive out of the shadowset to take the image backup. ... Note that if I am *planning* to do a restore I don't use incrementals, ...
    (comp.os.vms)
  • Re: Please critique my backup practices
    ... I assume you're talking about VMS Volume Shadowing. ... taking the drive out of the shadowset to take the image backup. ... Note that if I am *planning* to do a restore I don't use incrementals, ...
    (comp.os.vms)
  • Re: Please critique my backup practices
    ... I assume you're talking about VMS Volume Shadowing. ... close open files. ... taking the drive out of the shadowset to take the image backup. ... According to service techs that I talked to when I first set up ...
    (comp.os.vms)