Symantec Backup - Tape drive question

nevolved

Hi,

I really don't have much experience with Symantec Backup Exec, but I do have a plan!

I would like to use a single tape to perform Differential backups Mon-Fri night.

On Saturdays a Full backup will be completed to the same tape, and I want it to overwrite the full backup that was on it previously.

Monday morning the client will rotate the tape out. (5 total tapes)

What do you think?

RobertKaucher

nevolved wrote: »

Hi,

I really don't have much experience with Symantec Backup Exec, but I do have a plan!

I would like to use a single tape to perform Differential backups Mon-Fri night, and hopefully have them overwrite themselves.

On Saturdays a Full backup will be completed to the same tape, and I want it to overwrite the full backup that was on it previously.

Monday morning the client will rotate the tape out.


I've heard you can partition tape libraries, can you do that with tapes as well? Is the above possible?

I'm not sure that is possible, but I have a question regarding the logic: what happens when your single tape goes bad from over use and you cannot restore anything from that week? I imagine the intention is so that the client does not have to remember to swap out the tapes. My suggestion is that you try backup to disk and use the tapes for off-site. Keep the tapes to just a full backup once a week, maybe?

tiersten

nevolved wrote: »

I would like to use a single tape to perform Differential backups Mon-Fri night, and hopefully have them overwrite themselves.

On Saturdays a Full backup will be completed to the same tape, and I want it to overwrite the full backup that was on it previously.

Monday morning the client will rotate the tape out.

If I follow what you're trying to do, that is a very dangerous backup rotation scheme.

If anything happens that doesn't get noticed for a couple of days then you have no way of recovering from it since you're overwriting the incremental backup each day.

If any backup fails then you don't have any backup at all since the previous Saturday.

Tapes are cheap. Get your client to buy more and rotate them every day with a full backup if possible. This doesn't mean just having 5 tapes and just reusing them forever either.

nevolved wrote: »

I've heard you can partition tape libraries, can you do that with tapes as well? Is the above possible?

What do you mean? Like putting multiple individual backups onto a single tape?

blargoe

You can set the expiration on the backups to allow the jobs to overwrite backups, but if you do that, one of your diff backups could overwrite the full if the person changing the tapes isn't there on Monday, then you're screwed. Tape capacity is not expensive, you should be able to do full backups nightly pretty easily.

Daniel333

What are you exactly trying to achieve? Any reason you can't just run a full everynight to a different tape?

joey74055

Ditto to what everyone is saying. Buy more tapes and do Fulls if at all possible, at least one for everyday for 2 weeks (10 tapes) then rotate them back in and once a month do a Full and archive it offsite up to at least a year (12 tapes). This will give you 2 weeks of Full backups and a monthly Full backup for every month up to a year. If you can't do Fulls because there is to much data then try incremental backups with one weekly Full for up to 4 weeks and the monthly Fulls archived. The more tapes the better then you can do longer intervals. You have to remember that if you are backing up Exchange, SQL, application data that you will want that data on more than one tape becasue of what the others have said, the tapes do go bad and someone could miss putting the tape in. Someone will also need to make sure that the jobs all run correctly each night because if they don't and no one notices it defeats the point of running backups.

wedge1988

I have 12 tapes, 400gb a piece. I used to run a full backup of all servers each night, each on a separate tape for 2 weeks then rotate the cycle again. I wouldnt reccommend this, purely because users are dumb, and expect work from 5 months ago to be recoverable. (Trust me, if you think youve thought of everything then your wrong)

To answer your question: Erase a tape, and on that erase option (When the box appears asking you when to run), schedule the erase. Repeat the erase every monday for example. Ensure your protection is disabled to, or this will be pointless.

I wouldnt reccommed this, and backing up a week past is kind* of pointless, unless users delete data for fun! lol.

Id reccommend doing what i do now, run system center DPM 2007 for main backups and run one tape per month for archiving. 12 tapes = 1 year of monthly and multiple daily backups with DPM. Hard disks are cheap!

joey74055

wedge1988 wrote: »

I have 12 tapes, 400gb a piece. I used to run a full backup of all servers each night, each on a separate tape for 2 weeks then rotate the cycle again. I wouldnt reccommend this, purely because users are dumb, and expect work from 5 months ago to be recoverable. (Trust me, if you think youve thought of everything then your wrong)

The only way to get around this and not be liable for data that is inbetween Fulls is to get management to sign off on the rortation and interval cycle and to let management know about any data that could possible be unaccounted for because of time. The only way to save yourself is to let management know all the scenerios, daily Fulls everyday for x amount of weeks etc. and let them decide what they want to do. This way you are not accountable for missing data from several months ago if management wont allow the purchase of enough tapes for archival.

nevolved

Thanks for all the responses.

I didn't explain everything completely.

There are 5 tapes, which most likely will be rotated weekly because that is how the client wants to do it.


Diff M-F - Full Sat --- Change tape on Monday - take tape off-site

They have no need for archival, but will still be able to go back 5 weeks with this plan.

I have considered doing full backups nightly, but the client will have to change the tapes multiple times each week if we do that.


The question I was originally asking has been answered.. Thanks


Thanks for the suggestions,

phoeneous

Daniel333 wrote: »

What are you exactly trying to achieve? Any reason you can't just run a full everynight to a different tape?

Thats what I do. Everynight is a full backup. Incrementals and Diffs are just too time consuming to work with. With a full backup, I can restore a file within just a few minutes. No need to track down multiple tapes.

JBrown

phoeneous wrote: »

Thats what I do. Everynight is a full backup. Incrementals and Diffs are just too time consuming to work with. With a full backup, I can restore a file within just a few minutes. No need to track down multiple tapes.

Full backup in a few minutes:) love your setup. It takes almost 3 full LTO3 tapes with hardware compression on and 28 hours for me to finish the 1 full backup, 900 Gigabytes of data.
Thanks G-d for differentials, 80GB of data only 2 1/2 hours depending on the server.

Never ever underestimate the amount of data. When we moved to LTO3 (400/800GB) 2 tapes were enough to for fully backing up around 15 servers 3 times a month. And 2 years and almost 50 tapes later we are thinking of changing the LTO3 to LTO4(800/1600). The problem is, the freaking tape library machine with 8 cartridge magazine cost way too much.

tiersten

JBrown wrote: »

Full backup in a few minutes:) love your setup. It takes almost 3 full LTO3 tapes with hardware compression on and 28 hours for me to finish the 1 full backup, 900 Gigabytes of data.

Restoring a file takes minutes not doing a full backup.