backup solution - basic

[pendal1]

Guys, I work for an organization with a budget that is somewhat constricted by ancillary forces so please bear that in mind.
Here's my scenario: I'm in a building with one domain controller and one file server. I have a tape drive connected to the file server and I'm using windows to organize by backup process. Basically, I ran a normal or full backup of the user's shares, relevant software and the system state. Then on Friday I scheduled an incremental backup after hrs and these backups will be appended to the full backup. The tapes are 72gbs and the normal backups were approximately 8-10gbs. We really don't have an offsite storage center unless I take the tapes home. I know some of you may have more complex backup solutions but will this get the basic job done or do you guys forsee problems. Thanks in advance.

 

[Clowntrigger]

You should run the full backup once a week and run incrementals the rest of the weekdays. Your full backup will give you a snapshot for that day and incrementals will show the changes since then.

 

[pendal1]

I changed my backup schedule to a full backup every two weeks and the incremental backups every day. Is there a problem that in the schedule of jobs that the full backup and incremental backup are both listed. Will this cause any problems or will the full backup win.

 

[Clowntrigger]

I'm not sure which backup job will win. You should reconfigure your backups so that only one job is listed for each day.

 

[scheesman]

How many tapes do you have? If you have enough tapes to do a decent rotation, I would just run a full backup every day. Even if you don't have a tape for every day, your backups are only 1/8 capacity on the tape (assuming 2:1 compression). Incremental backups can be a lifesaver and a necessity when you have a huge amount of data or a short backup window. But they can be complex to restore from. I'm just not sure you need that level of complexity. Or am I missing something?

 

[ntinlin]

If that is your only DC then you have a problem.

Windows cannot backup the System State of a remote system directly so you would have no backup of AD, group policy etc.

Neill

 

[pendal1]

I don't have a lot of data changing daily, at least right now but I work in a school system and some of the student data changes daily so that would be something we would want restored quickly.
I've looked at the scheduling and I don't see a way around having the full backup run every two weeks and the incremental run every day without the two of them overlapping. Again, I'm using windows to organize my backups. Maybe I'm missing something but I don't see a way to schedule the incremental backup daily so it doesn't overlap with the biweekly fully backup. Any help would be appreciate there because I don't want a scheduling conflict to cancel out the jobs.
For nitinlin, I wasn't clear in my posts. The domain controller and the file server are one and the same - for the time being so I am able to backup the system state because it is local.

 

[LWComputingMVP]

I would not use incremental backups - I would use DIFFERENTIAL backups. Incremental backups can be a nightmare to restore. Though I wouldn't go against a full every night given your backup sizes... but if they grow much, I would reconsider.

You can backup the DC easily by simply backing it up to a file on the file server and letting the file server backup the file to tape...

 

[ntinlin]

Ah, being one and the same makes all the difference.

Neill

 

[LWComputingMVP]

Differentials and incrementals are NOT one and the same... a differential backs up all changed data since the last full.

An incremental backs up all changed data since the last backup, marking anything backed up as being backed up.

Assume you have a full backup on Friday nights and Incrementals Monday, Tuesday, Wednesday and Thursday. IF your server fails Friday at noon, you need to perform 5 different restores - the full, and then each incremental from the last 4 days.

With a differential, the same scenario only requires TWO restores, the full and the backup from Thursday night.

 

[ntinlin]

I meant that the DC and file server are one and the same, not incrementals and differentials.

I would certainly agree with using differentials between the full backups.
If the tapes are only 72Gb I'm presuming its some sort of DDS.
How long does it take for a full backup? As LW says if the backup is small enough and short enough for your backup window you might as well do full backups each night.

Oh, just noticed you mentioned appending to a full backup. I would personally NEVER do this and I'd also be hesitant to append to an incremental or differential tape as well.
Think all eggs in one basket, tapes are cheap relatively speaking.

Neill

Neill

 

[LWComputingMVP]

So how many tapes would you have for this? Tapes should be rotated, but I see no significant risk if appending data to them.

 

[ntinlin]

I've had too many tapes wind themselves right out of the cassette to ever put more than one backup of any form on a single tape. Thus speaks an ex-hardware engineer.


If you do a full backup on the friday night on one tape then use 1 other tape to do all the daily inc or diff backups and it screws up on Thursday night then you've lost a week. It isn't worth it to save a few $'s.

Apologies if this isn't what you meant LW.

Personally for something as small as this I'd do fulls every night with a 2 or 3 week cycle or a full on a Friday and diffs the other 4 nights, again on a two or three week cycle. Which amounts to the same thing in number of tapes really with the small amount of data being used.



I'm presuming DAT72 tapes so that would cost a grand total of $200-300 for tapes which even with a restricted budget is worth it.

I'd also turn on Shadow Copies and distribute the client to the workstations for version recovery if there is enough disk space.

Neill

 

[LWComputingMVP]

I view Volume Shadow Copy as a requirement if you have Server 2003. At worst, you can add another disk purely for that - even a SATA controller and cheap SATA disk. (I would always prefer Shadow Copy on a different spindle than the rest of the system for performance reasons).

I don't mean that you wouldn't change the tape on a nightly basis - you would. Differential tape for Monday, another for Tuesday, etc. Actually, I'd rather have 6 tapes and go something like this:

Mon-1
Tue-2
Wed-3
Thu-4
Fri-5F
Mon-6
Tue-1
Wed-2
Thu-3
Fri-4F
etc.

To me, this "wears" the tapes evenly - after 6 weeks, each has a full and maybe then you wipe a tape a start over while putting another in semi-permanent storage. Or start a fresh new batch and (pending data growth) you have a second 6 week set. Rotate those and you have always have at least 6 (and up to 12) full backups to fall back on and only use 12 tapes total.

 

[ntinlin]

It's amazing how many people don't know about or don't implement Volume Shadow Copy though.

Neill

 

[pendal1]

ntinlin and LWComputingMVP - question...
I read your posts and let me clarify something and then get your opinion. I'm dealing with multiple buildings here - a school district - and currently our storage system is not centralized so there's no way for me to change tapes every day. Just with the schedule we have - I'm not in the various buildings every day. I have ordered more tapes (4mm dat dds 72gb) but I still won't be onsite every day to change them. I would love to run a full backup every day and we could get away with this because the longest backup for any of my file servers was approximatly six hours. However, for now the only thing I could do is schedule a full backup every day replacing the previous days backup but using the same tape. This doesn't thrill me but it's the only way I'm getting a Full Backup in every night. Our data doesn't change that much (trust me on this) so I was even thinking of running a Full Backup on Friday and a differential on Wednesday. I could probably change the tapes twice a week but even that would be hard but I don't want to apprend anything to my full backup. Anyway, what are your thought or anyones thoughts on this dilemma.

Additionally, have any of you created the full backup with windows where your prompted to make the automatic system recovery disk on a floppy. I made the floppy but in the event the floppy turned out to be a dud I'm assuming I can reinstall windows and then run restore my full backup. Is this correct. Thanks again for the info.

 

[LWComputingMVP]

If your data doesn't change often, then your differentials are probably small. It would seem that a single tape might be able to hold a full and 4-6 differentials - so you could change them once a week and yet do backups every night... (There are some things that might warrant no backing up daily... but I really prefer one backup a night). Another thing to consider, since your backups don't change much, do a full once every two weeks or every month... leaving one tape for differentials the rest of the time. So lets say you do this:

You start out with a full backup and then let the differentials run on the same media for the next couple of nights until you get there. Then you take the full tape off site and replace it with one to be used for differentials over the next 3 weeks. In week 4, you return, put a fresh tape in to ensure there's sufficient space for a new full. Determine how many fulls you want to keep and then start recycling.

There is a drawback to that in that if the building burns down (or similar) sometime in week 3 you have no recent backups and 3 weeks of data is lost... but if it doesn't change much, then maybe this is acceptable.

Another thing to consider... for truly critical data, you can use an online backup system or a secure file transfer method to forward the data to another location. If you were a small business with 6 branches, I'd describe it as your accouting data at HQ getting transferred nightly to a remote system at another branch. This way, the most critical data is backed up twice AND offsite every night.

 

[pendal1]

Thanks LWComputingMVP. I'm definitely going to try one of your scenarios. I'm leaving toward the biweekly or monthly full backup and differentials every night. Another question: have you used the windows backup process and created the ASR disk (floppy). I was just wondering if this worked (you use this in conjunction with your full backup) and then it supposedly restores windows in the event of a failure along with your data. However, would I be able to just reinstall windows and then run my full backup without using the ASR disk. I'm assuming I can but I've never done it before. Thanks again. Very helpful information.

 

[LWComputingMVP]

I have not used the ASR function of NTBackup... It is something I'm curious about and when I have time, I want to test it... (Of course, I'm still trying to find time to setup my NT4 test network... so when that will happen, who knows).

 

[ntinlin]

There is no way to get a local staff member to change the tapes for you?

That's a good idea of LW's on file transfer / online backup.


If you have a reasonable speed link to wherever your office is for instance and the data isn't changing much or the data that does change isn't too big you could do something as simple as a Robocopy to get the files with the archive bit set across to a cheap and cheerful NAS drive or similar.

Neill