--On Thursday, October 28, 2004 20:00:28 +0000 James Marcinek <jmarc1 AT
jemconsult DOT biz> wrote:
> Frank,
>
> Thanks for the reply. My wheels were spinning but I was getting nowhere. It
> appears that the 'Red Hat Bible' shows the traditional backup approach (This
> helped in the confusion). It actually used the full and incremental approach;
> however it only gave the 'always-full' backup type which is easy enough to
> understand. I've actually been exposed to backup apps (from EMC) that allows
> the
> application to decide when the full backups occur. I guess one question would
> be
> "when will it do a full backup and how does it make the determination".
Amanda will do 'at least' one full backup per dumpcycle. Of course, before
it can do an incremental it has to do a full, so it's best to add your new
disklist entries (DLEs) a few at a time. Thereafter Amanda's scheduler
will move the fulls to different days and adjust dump levels in order to
use about the same amount of tape each day (while ensuring that you get
at least one full per dumpcycle).
>
> What type of dump would be recommended. The backup server will be primarily
> backing itself up and it was created using only 1 partition (I didn't do it
> this
> way), so the holding disk and the amanda directories are all on the same
> partition:
>
> config directory:
> /etc/amanda/normal/amanda.conf
> /etc/amanda/normal/disklist
> /var/lib/amanda/normal
> /var/lib/amanda/normal/index
>
> holding:
> /var/holding
>
> I will be adding other clients later and I know they will not be a problem;
> however the amanda.conf dumptype comments concern me.
>
> The drive is currently 70Gigs with about 46% utilized, however it is expected
> to
> grow. The tape drive is:
>
> Host: scsi0 Channel: 00 Id: 06 Lun: 00
> Vendor: ARCHIVE Model: Python 06408-XXX Rev: 8250
> Type: Sequential-Access ANSI SCSI revision: 03
>
> One other thing does confuse me about spanning multiple tapes? Does this mean
> if
> I'm doing a backup and I need another tape that it will start the backup from
> beginning?
A single DLE can't exceed the size of a single tape (unless you want to
test the tape=spanning patches). You might need to use tar instead of
dump on your large filesystem and backup subdirectories.
If runtapes is > 1 then Amanda will use multiple tapes per run, but
each DLE must be smaller than a single tape. If Amanda hits EOT before
it has written tapelength bytes, it will restart the failed DLE on the next
tape.
Frank
>
> Thanks,
>
> James
>
>
>
> Frank Smith <fsmith AT hoovers DOT com> wrote:
>> --On Tuesday, October 26, 2004 18:07:30 +0000 James Marcinek
> <jmarc1 AT jemconsult DOT biz> wrote:
>>
>> > Hello all,
>> >
>> > I'm getting ready to start using Amanda as a backup solution. To prepare,
> I've
>> > read the online documentation and I've also read a section in the Red Hat
> Linux
>> > Bible. I also read through the FAQ's. I am a bit confused with some items.
>> > Mainly the configuration. The amanda comes with the DailySet1 as an
>> > example.
>> >
>> > Is it possibly to only use 1 configuration (eg DailySet1) to accomplish
>> > both
> the
>> > full and the incremental backups? From past experiences with other backup
>> > utilites, one would create and schedule both full and incremental's (as
>> > does
> the
>> > Red Hat Bible's example). The thing that further confuses me is how to
> define an
>> > incremental. The backup for the full is easy enough in the disklist file to
> call
>> > the 'always-full' definition. Where I'm confused is which types are for the
>> > incremental. From what I've read some of the attributes it looks as if it
> can
>> > figure this out with the following settings. The following is from the
> example
>> > amanda.conf file. I've added what I think I want to accomplish as well:
>> >
>> > dumpcycle 4 weeks # the number of days in the normal dump cycle
>> >
>> > I'm planning a weekly cycle: Every Friday a full backup so I'm assuming it
> would
>> > be:
>> >
>> > dumpcycle 1 week
>> >
>> > runspercycle 4 weeks # the number of amdump runs in dumpcycle days
>>
>> 'runspercycle' is just a number, it has no units. It just tells Amanda
>> how many times it will run during the dumpcycle so it can schedule
>> appropriately to level out the backups.
>>
>> >
>> > Now I'm planning on doing incrementals from Monday - Thursday and a full on
>> > Friday:
>>
>> That is the 'traditional' backup schedule, and it is possible to do that
>> with Amanda, but it really isn't the way Amanda was designed to run.
>> Normally, Amanda scatters the full backups across the dumpcycle so as to
>> use about the same amount of tape each day. You will still have a
>> full backup done every (in your case) week, it just won't necessarily
>> be on a Friday.
>> Unless you have a real need for your fulls to only run on Friday, I
>> would suugest keeping things simple and just let Amanda do her thing.
>> If you must have only fulls on Friday and only incrementals during the
>> week, then you need two configs, one for the fulls and one for the
>> incrementals.
>>
>> >
>> > runspercycle 5 days ???
>> >
>> > tapecycle 25 tapes # the number of tapes in rotation
>> > # 4 weeks (dumpcycle) times 5 tapes per week (just
>> > # the weekdays) plus a few to handle errors that
>> > # need amflush and so we do not overwrite the full
>> > # backups performed at the beginning of the
>> > previous
>> > # cycle
>> >
>> > I understand I have to figure out what my capacity requirements are.
>> >
>> > If one configuration for the full and one for the incrementals are needed
> I'd be
>> > interested in how these are configured...
>> >
>> >
>> > I'm also looking for advice on recommendations for single tape drives for
> linux
>> > as well as media types. I don't want to further complicate my introduction
> with
>> > additional configuration issues.
>>
>> We would need more information to recommend drives. It depends on
>> how much data you have, how long your backup window is (or not, if
>> you have plenty of holdingdisk space), how many tapes you need in
>> rotation (if media cost is an issue), and the server hardware (if
>> you have a very low-end server it may not be able to feed some of
>> the latest drives fast enough, so the extra cost might not be worth it).
>> Depending on your backup needs, you might also consider backing up
>> to disk instead, possibly doing occaisional archive backups to tape
>> as well.
>>
>> Frank
>>
--
Frank Smith fsmith AT hoovers DOT com
Sr. Systems Administrator Voice: 512-374-4673
Hoover's Online Fax: 512-374-4501
|
