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This was originally posted in the wrong forum.. .. blame the new guy smile.gif


Because of some unique requirements I would like to do a weekly backup of all the servers and then a nightly incremental or normal to a seperate tape each week night. The reason is my desire to have the most current tapes off site every night. That way in the event of total loss of the building I've got a complete image of the system off-site in a safe. My exposure is then only one days work. I've worked with tech support once on this with out success. Every other product I've used has a method to do this. I must be missing something. Any help or ideas would be appreciated.



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If you can't see how Set-based strategy is an advantage, then you can just make yourself a new Selector, and "Include everything... but always exclude files matching Windows Attribute Archive Bit is not set". Then in your backup options, turn on "Windows, System, Clear archive attribute", so it unsets the Archive bit when it backs up the file. Now it will work just like everyone else's backup software.




Retrospect backs up two ways; "normal" and "recycle". To understand this, you just have to stop thinking in terms of "Archive bit" on each file.




Recycle erases the Backup Set and starts over.




Normal adds to the Backup Set, and unless you change the options it does not add duplicate files that are already in the Set.




You want to take a tape offsite each night and have full recoverability in the case of a disaster, so you need at least two Backup Sets. If you never want all your sets in the same place you would need to make extra trips offsite, or have three sets.




Lets say you have Set1, Set2 and Set3. Your Monday backup puts every file (except temporary and cache files, perhaps?) in Set1. You take it offsite. Your Tuesday backup puts every file in Set2. This duplication is one way you probably don't like how Retrospect is different, but bear with me and you will understand it. You take Set2 offsite. Your Wednesday backup puts every file in Set3. You take Set3 offsite.




Why all the duplication? Because each set is an individual recovery unit that doesn't depend on the other sets. Here is where Retrospect actually gets better than backing up based on Archive Bit:




Thursday, you bring Set1 onsite, and back up Normal to it. It gets every file that doesn't match what is in Set1, in other words, since Monday. It skips files that are the same, so you don't back up Windows XP SP1 from each workstation you back up because they are all the same files. This can actually make that Monday backup much smaller than "the competition" because of the fact that it skips all files already in the set. If you back up 50 clients, you back up all the files when it does the first client, but then you skip duplicate files like Windows XP and Office XP on the 49 other clients because those files are already in the set. If you only back up one file server, this won't be so much of an advantage to you.




Friday, you bring Set2 onsite. You back up Normal to Set2. It gets every file that doesn't match what's in Set2, in other words, since Tuesday. You see how it goes.




You can play out how a disaster would effect your tapes. It is possible that two Backup Sets are onsite and destroyed, or there could be only one onsite when disaster strikes. Think about how restoring would work. In my example, it's Friday, and you've brought Set2 onsite. If you've taken Set1 offsite, and disaster strikes, you won't lose it. You lose Set2, but you have everything in Set1 you need. If Set1 and Set2 both burn to the ground because you haven't left with them for the day yet, you still have Set3, although it hasn't been updated since Wednesday.




I didn't even mention how snapshots let you restore exactly how things looked when they were backed up. If you've deleted a bunch of files, they aren't restored because the snapshot knows they were gone at that time.



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Wow!, that's really helpful. Thanks..

You're right I tend to think in archive bit terms, old habits and such. I was considering using multiple tape units and splitting the servers I back up into groups that back up to one tape unit or the other. Our facility runs around the clock and so my backup window is short and in the middle of the night. I like the approach you've suggested and will use it. I assume that I can create the two groups of servers and sets and point them to tape drive 1 or 2 running simultaneously.

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One of the multi-star posters stated the rules for concurrent executions in another thread.


Quoting the User's Guide:

"If a specific source or destination is in use by one operation, Retrospect cannot use that source or destination for another concurrent operation"


and of course,

"You must have at least two execution units available to run multiple concurrent operations"


So you have to make sure that you have two separate sources, as you said, and that the tape drives are separate destinations, and it can do them simultaneously.

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  • 3 weeks later...

Hey guys Im new to this program as well and have setup a backup and wanted some feedback on how I did.


1. Setup 5 backup sets ( one for each day)

2. Setup 5 different scripts (one for each day useing the same Day backup set)

3. made all backups recycle backups (so it backsup everything that is selected).


Is this a bad way to do the backup? Reading the above post its looks like there is a better way but the manual didnt help me very much. If I do normal backups then I run out of room on the tape farely quickly I found. I need a backup script that I can setup and leave alone and just switch tapes everyday. (remote site that Im not at very often). BTW I am backing up exchange and SQL as well.

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