Monthly archival tapes

Joe Donner (sent by Nabble.com) wrote:

dumpcycle 0 (to force a full backup on every run, because all our data fit
comfortably onto a single tape every night, and amdump only runs for 4.5
hours)

Lucky you :)

runspercycle 5 days (to do an amdump each day Monday to Friday)
tapecycle 21 tapes (to have 4 weeks' worth of "historical backups" + one
extra tape for good measure)

How do I now handle taking out one tape a month for long-term archiving?

If my tapes are labelled daily-1, daily-2, etc., then how do I take out one
tape a month but make sure that this doesn't confuse amanda, and that I will
be able to restore from that tape in the future?

Just pick the tape you want to take out of the rotation and mark it as
no-reuse with amadmin.

Do I add a new tape each time in my numbering sequence?

IMH this is the best solution. Just add in a new tape and amlabel it
with next number.

Can I reuse tape labels but somehow cause amanda to not overwrite the
information needed to do restores from the archived tapes?

I guess you could maybe do this if you really want to. Copy the
necessary log and index files to somewhere outside the Amanda
directories, then amrmtape the archived tape and amlabel the new tape
with the same label. Then you could use amrestore to restore from these
tapes without indexes, or copy in the index and log directories you
previously moved out of the way and use amrecover. But I think this way
you would just make restoring more difficult for yourself. And restoring
is the part of backup that really should be easy, because often you need
to do it quickly with The Boss breathing at your back :)

In your place I would just keep on labelling new tapes with
ever-increasing numbers. Actually, this is exactly what I do in my setup.

Tue, Aug 08, 2006 at 08:51:32AM -0700, Joe Donner (sent by Nabble.com) wrote:

The amanda configuration I'm planning to put live this week includes these
entries in amanda.conf:

dumpcycle 0 (to force a full backup on every run, because all our data fit
comfortably onto a single tape every night, and amdump only runs for 4.5
hours)

Gee, I thought it took about 53 hours for your taping.
you reconnected the cables huh? ;))

runspercycle 5 days (to do an amdump each day Monday to Friday)

No, that is runs per dumpcycle. Your dumpcycle is basically 1 day,
you are only doing one run per day.

tapecycle 21 tapes (to have 4 weeks' worth of "historical backups" + one
extra tape for good measure)

How do I now handle taking out one tape a month for long-term archiving?

You could use a lower tapecycle setting but really use 21 tapes.
Then amanada wouldn't care if one went away. , add a
newly labeled tape.

If my tapes are labelled daily-1, daily-2, etc., then how do I take out one
tape a month but make sure that this doesn't confuse amanda, and that I will
be able to restore from that tape in the future?

amadmin <confignoreuse tapelabel

Do I add a new tape each time in my numbering sequence?

Can I reuse tape labels but somehow cause amanda to not overwrite the
information needed to do restores from the archived tapes?

Not with amanda capabilities.
How about when you remove daily-9, you make a new tape as daily-9b
or daily-9.1. Reset your label string appropriately.

8 Aug 2006, at 19:02, Toomas Aas wrote:

Joe Donner (sent by Nabble.com) wrote:
>
>dumpcycle 0 (to force a full backup on every run, because all our
>data fit
>comfortably onto a single tape every night, and amdump only runs
>for 4.5
>hours)
>
Lucky you :)
>
>runspercycle 5 days (to do an amdump each day Monday to Friday)
>tapecycle 21 tapes (to have 4 weeks' worth of "historical backups"
>+ one
>extra tape for good measure)
>How do I now handle taking out one tape a month for long-term
>archiving? If my tapes are labelled daily-1, daily-2, etc., then
>how do I take out one
>tape a month but make sure that this doesn't confuse amanda, and
>that I will
>be able to restore from that tape in the future?
>
Just pick the tape you want to take out of the rotation and mark it
as no-reuse with amadmin.
>
>Do I add a new tape each time in my numbering sequence?
>
IMH this is the best solution. Just add in a new tape and amlabel
it with next number.
>
>Can I reuse tape labels but somehow cause amanda to not overwrite the
>information needed to do restores from the archived tapes?
>
I guess you could maybe do this if you really want to. Copy the
necessary log and index files to somewhere outside the Amanda
directories, then amrmtape the archived tape and amlabel the new
tape with the same label. Then you could use amrestore to restore
from these tapes without indexes, or copy in the index and log
directories you previously moved out of the way and use amrecover.
But I think this way you would just make restoring more difficult
for yourself. And restoring is the part of backup that really
should be easy, because often you need to do it quickly with The
Boss breathing at your back :)

In your place I would just keep on labelling new tapes with ever-
increasing numbers. Actually, this is exactly what I do in my setup.

Tue, Aug 08, 2006 at 09:22:20PM +0100, Alan Pearson wrote:

Guys,

this subject, I'd like to do something similar. Unfortunately my
backups don't fit on one tape !
How can I take a _complete_ backup off site in this situation, and
how can I identify which tapes I need to take ?

I'd recommend a separate config of no-record, full dumps only.

But assuming you can't, the answer is complicated.

Nominally you need any dumpcycle's set of tapes. It doesn't matter
which day you start, any sequence of a dumpcycle's number of tapes
should contain a level 0 of each DLE from someday within that cycle.

How many tapes are in a dumpcycle? Well, the max should be
runtapes X runspercycle. But if runtapes is 1 and the same
number of tape is not used each day, how many were used in the
dumpcycle you are collecting?

Furthermore, there can be multiple dumpcycles and runspercycles in
a single config. These parameters can now be set differently in
different dumptypes. So which do you use in collecting your tapes?

Another "potential" problem to look out for is DLEs that should
have had their level 0 on the last tape you select but due to some
error (eg. system down or tape problems leaving some things on
holding disk for taping next run), you might not have a level 0
of each DLE on the tapes you select.

I don't know of any tool that would let you do something like:
"given a date (or a tape), determine the minimal collection
of tapes, going forward or backward, that contain at least one
level 0 (successful dump and taping) of each DLE".

Could be a useful tool.

Wed, Aug 09, 2006 at 10:27:36PM +0100, Alan Pearson wrote:

9 Aug 2006, at 15:15, Jon LaBadie wrote:
Tue, Aug 08, 2006 at 09:22:20PM +0100, Alan Pearson wrote:
>>
>>
>>Guys,
>>
>this subject, I'd like to do something similar. Unfortunately my
>>backups don't fit on one tape !
>>How can I take a _complete_ backup off site in this situation, and
>>how can I identify which tapes I need to take ?
>
>I'd recommend a separate config of no-record, full dumps only.
>

Thanks for the answers guys, I'm tempted to have different config for
this, given the ease at which I can.
The only question is then what happens if it all doesn't fit on one
tape ?
Just amflush to as many tapes as required ?

Essentially yes.

Considerations:

Make sure record is set to no. You don't want a record of this
full dump upsetting the scheduling of your daily config.

Make sure index is yes.

Make sure runtapes is sufficient. Make it big, amanda will only
use what it needs anyway and you will only be running this manually
or infrequently. If runtapes is too small amanda will, during planning,
think it has too little tape space and not schedule some dumps.

If you have sufficient holding disk space, let it all collect on the
holding disk (leave out the tape) and do the taping with amflush.
By having all the dumps available at the start, the taper algorithm
"largestfit" can be more effective.

Set a suitable taperalgo.

Set your holding disk reserve to 0, you won't be doing any incrementals.

If on a 2.5 or greater server version, consider tape spanning.

HW compression rather than SW? Faster dumps, larger holding disk usage.

Consider dump vs tar if you don't need tar'isms like exclude.
Probably faster, probably saves ACL's and devices (dubious value).

No need for precise estimates, so use one of the much more efficient
estimating procedures.

?

Hi,

thanks again for the replies. I think Jon's suggestion of using labels such
as daily-9b sounds like the best option in my case.

Yep reconnecting the SCSI cables cut amanda's dump time in half! Whoohoo!

If I did change to incremental backups in future, then I assume this would
then be correct, right?

dumpcycle 7 days (full backup once every 7 days, with incrementals
in-between)
runspercycle 5 days (amdump runs 5 times per dumpcycle - Monday to Friday)
tapecycle 21 tapes (4 weeks' worth of backups + 1 tape to prevent
overwriting a last level 0)

I also have that problem where my first 5 tapes are requested out of
sequence by amanda, so if I leave the tapecycle at 21 tapes, but actually
use 26 tapes, then I'd be able to fix that issue too by the time amanda has
ran through the entire set of tapes? Is that correct?

Regular expressions do my head itbut I've come up with this to enable me
to label tapes daily-1 or daily-1b, etc:

labelstr "daily-[0-9][0-9]*[a-z]*"

:)

Jon LaBadie wrote:

Tue, Aug 08, 2006 at 08:51:32AM -0700, Joe Donner (sent by Nabble.com)
wrote:
>
>The amanda configuration I'm planning to put live this week includes
>these
>entries in amanda.conf:
>
>dumpcycle 0 (to force a full backup on every run, because all our data
>fit
>comfortably onto a single tape every night, and amdump only runs for 4.5
>hours)

Gee, I thought it took about 53 hours for your taping.
you reconnected the cables huh? ;))

>runspercycle 5 days (to do an amdump each day Monday to Friday)

No, that is runs per dumpcycle. Your dumpcycle is basically 1 day,
you are only doing one run per day.

>tapecycle 21 tapes (to have 4 weeks' worth of "historical backups" + one
>extra tape for good measure)
>
>How do I now handle taking out one tape a month for long-term archiving?
>

You could use a lower tapecycle setting but really use 21 tapes.
Then amanada wouldn't care if one went away. , add a
newly labeled tape.

>If my tapes are labelled daily-1, daily-2, etc., then how do I take out
>one
>tape a month but make sure that this doesn't confuse amanda, and that I
>will
>be able to restore from that tape in the future?

amadmin <confignoreuse tapelabel

>
>Do I add a new tape each time in my numbering sequence?
>
>Can I reuse tape labels but somehow cause amanda to not overwrite the
>information needed to do restores from the archived tapes?

Not with amanda capabilities.
How about when you remove daily-9, you make a new tape as daily-9b
or daily-9.1. Reset your label string appropriately.

Thu, Aug 10, 2006 at 01:40:45AM -0700, Joe Donner (sent by Nabble.com) wrote:

Regular expressions do my head itbut I've come up with this to enable me
to label tapes daily-1 or daily-1b, etc:

labelstr "daily-[0-9][0-9]*[a-z]*"

:)

Looks good. Would even match daily-8004amanda