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Maintaining an exact match between my internal hard drive and the backup on my external drive

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I recently backed up my entire hard drive on my Mac on my My Book Pro external hard drive using EMC Retrospect Express. I changed some files around and when I backed up again, it appropriately updated just the files that changed. But I have since deleted some files on my internal drive, that I want to be similarly deleted from the backup on the external drive. I ran another backup, and it didn't seem to process this:

 

1) How do I delete a file on my internal drive and have it delete on my external drive when I run the next backup?

 

2) What is the best way to view my files that currently sit on my external drive after they have been backed up (to confirm if something is there or if it's been deleted, etc.) ? When I go to my Mac view finder, I just see 2 back up files. I know that all of my hard drive files are there because the disk has been depleted, but I can't see a list of all of the files. I don't necessarily need to see the catalog of what I backed up on each back up session. I just want a comprehensive list of what sits in the external drive.

 

If anyone could help me out, I would really appreciate it!!

Thanks!!!!

-Scott

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Scott,

 

You don't say whether you did a Retrospect "duplicate" (not a backup) or a Retrospect "backup" (not a duplicate), but your second item implies (because there are only 2 files) that you did a Retrospect "backup", which creates a retrospect database index ("catalog") and backup database ("backup set") on the destination. The only way to view the contents of this database is by using Retrospect, which lets you have different views ("snapshots") of the data in the database. That's the power of the Retrospect paradigm, as contrasted with the "full" with plethora of "incrementals" paradigm used by other backup programs.

 

The backup set holds all of the backup history, in case you wanted to restore to any snapshot in the backup set's life. The Windows version of Retrospect permits "grooming", which can remove older snapshots from the backup set, but the Macintosh version cannot do this.

 

Does that clear things up?

 

Russ

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Hi Russ,

I guess I'm still a bit confused. Yes, I did a "backup." I have a Mac, which I guess is unfortunate that I cannot perform the "grooming," but in that case, can I just go directly into the external drive and delete the file(s) directly?

 

1) If so, how do I delete items directly from the external hard drive?

 

2) What is the difference between the "duplicate" and the "backup?" My main objective is to make sure my files on my internal drive are backed up appropriately, and I do like how Retrospect has the function which recognizes just the files that have changed or are new, and only backs those up. But can it do that with the "duplicate?" What would be the best option for me to do? It sounds like you're saying that the "backup" option doesn't give me full access to my files...is that correct?

 

3) How do I view the files using the snapshot feature?

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Quote:

can I just go directly into the external drive and delete the file(s) directly?

 


No, because they aren't files; they are data in a database. It takes the Retrospect program to access that database, and there isn't a manual "grooming" feature to permit removal of files (data) from the database. You can only add to the database (by doing a backup) and retrieve from the database (by doing a restore).

 

Quote:

1) If so, how do I delete items directly from the external hard drive?

 


Well, you can delete the entire backup set and lose all of your backups and history. You can "recycle" the backup set, which is a cleaner way to do the same thing.

 

Quote:

What is the difference between the "duplicate" and the "backup?

 


Duplicate simply copies selected files, and does not use the Retrospect "backup" paradigm.

 

Quote:

It sounds like you're saying that the "backup" option doesn't give me full access to my files...is that correct?

 


Not sure what you mean here. You have to access the data in the backup set using Retrospect. But you can't delete individual files in the backup set, and you can't view the files using the Finder. Think of it as a black box container.

 

Quote:

3) How do I view the files using the snapshot feature?

 


Using Retrospect.

 

I may be confusing things a bit here. You say you are using Retrospect Express; there are a number of versions of Retrospect (and of Retrospect Express). I was under the impression that the current version of Retrospect Express was just a crippled version of the full Retrospect, that had certain capabilities removed:

Retrospect Product Comparison Matrix

Retrospect Express product description

 

We use Retrospect Workgroup, not Retrospect Express. But I had thought, from the comparison matrix, that the basic functionality was the same. They do use the same RDU and file formats and preferences; the license key determines the capability. I may be confusing you if my understanding is not correct.

 

Here's a discussion of using "Duplicate":

Using Duplicate in Retrospect or Retrospect Express

 

Here's a discussion of how to browse snapshots in Retrospect Express (looks very similar to Retrospect non-express):

Browsing Snapshots in a Backup Set

 

Regards, and hope this helps,

 

Russ

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Thank you so much for your responses- it's extremely helpful. I read the links you suggested, and if my understanding is correct, the "Duplicate" feature using the "Replace Entire Disk" selection is a much better option because:

a) It will "not re-copy any files that are identical to files already on the destination drive"...so it won't take so much time to copy the files- it will just copy the new/changed files.

 

B) If I delete a file on my internal hard drive, it will indirectly be deleted from the external drive when I "duplicate" the next time because it creates an exact duplicate.

 

c) I will be able to access my files on the external drive, using the Mac finder format...not just view them via the "database" you were talking about. (and plug the drive into another computer that doesn't have the Retrospect Express software, and be able to access my files)

 

Is my understanding correct? If so, it seems the that "Duplicate" selection is much better than "Backup"...am I missing something?

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Quote:

Is my understanding correct?

 


Yes.

 

Quote:

If so, it seems the that "Duplicate" selection is much better than "Backup"...am I missing something?

 


Just don't confuse duplicate with backup. A duplicate is not a backup. If you accidentally delete a file, or if a file becomes inadvertently changed (whether intentionally or not) or damaged, etc., you will not have an earlier copy to retrieve. That's what a Retrospect backup is for. For example, using Retrospect, we can go back to the state of any disk drive, on any day, that has ever been on our network since 1992, and retrieve any file or group of files, or even image a drive for booting as it was on that day.

 

If what you really want is for your destination drive to become a clone (or "copy") of your main drive, well, candidly, there are better tools (even free) for that job than Retrospect. SuperDuper! is one, Carbon Copy Cloner 3.0 (just released, by Mike Bombich) is another. Another approach, if what you are concerned about is failure of one disk, is to create a RAID 1 mirror, such that the two disks constantly stay in sync. There are several RAID 1 mirror solutions, but I suggest SoftRAID, which works very well and has excellent support. Use Google to find them. But, again, they aren't Retrospect, and aren't solving the problem that Retrospect solves (backup).

 

Russ

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Thanks Russ,

That makes a lot more sense. While the duplicate feature seems great, it seems like the "backup" option is a much more reliable feature.

 

-When you say that the backup is on "our network," what do you mean by that? Isn't the data just stored on my drive...not a network?

 

-Does the data compress or something when it runs the "backup?"

 

-By running the "backup," that's all I need to do to fully backup the drive, right? I.e. If my internal hard drive shuts down, everything up to the last time I backed up with be properly stored on my external drive, right?

 

Thanks again for all of the help with this!!!!

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Questions answered out of order:

Quote:

-Does the data compress or something when it runs the "backup?"

 


If you have compression turned on in Retrospect - it's a preference. Most tape drives have hardware compression, too, which is faster. We use hardware compression on our tape drive, and Retrospect will use hardware compression if it is available, unless you disable it. Whether your data is compressible depends on the nature of the data. There's an article in the Retrospect KnowledgeBase on that.

 

Quote:

-By running the "backup," that's all I need to do to fully backup the drive, right? I.e. If my internal hard drive shuts down, everything up to the last time I backed up with be properly stored on my external drive, right?

 


Ah, that's a real can of worms. What you are asking about there is what is called "bare metal restore" - What do you have to do to go forward from putting a new drive in your computer to getting back to where you were.

 

It's a bootstrapping issue. You need to have an operating system to run Retrospect, and then to install the backup. There are two ways to do this. One way is to create an emergency boot CD/DVD, with an OS and Retrospect on it. Retrospect used to have such an emergency boot CD/DVD, but it hasn't been updated in a very long time, and it will no longer boot the newer Macintoshes. There have been, shall we say, many cries from users for EMC to update that image, but, for some reason, EMC refuses to pay the $$$ to Apple for a current emergency boot image that EMC could modify with Retrospect on it.

 

It is possible but non-trivial to create such an emergency boot CD/DVD from your installer CD/DVD that came with your Mac. But you really have to know what you are doing - you have to hack some plists in order to get Retrospect to appear in the Installer's Utility menu, etc., you have to install Retrospect and RDUs, and, if you have a configuration like ours with special hardware, you have to install additional drivers for RAID, etc. I've done that, but you get in to a cat-and-mouse game of updating it for newer Retrospect RDUs, Retrospect updates (well, those don't seem to come any more, now), and Apple OS updates, perhaps. If you had such an emergency CD/DVD, you would just pop it in, run Disk Utility to format your new drive, then run Retrospect to restore the most recent snapshot.

 

Lacking such an emergency boot CD/DVD, you have one of two choices:

 

(1) get another spare drive, install the OS on that spare drive, install Retrospect on that spare drive, boot from that spare drive, restore from most recent Retrospect snapshot. This is the preferred method, and we have a spare FireWire drive hanging around with Retrospect installed on it, just in case such an emergency happens to our server. In fact (see below), that spare drive was created as a RAID 1 mirror split of our server's boot volume, so it has the current copy of Retrospect on it, and is a bootable drive for our server, already configured. So, if we lose the boot volume, we just boot off of that drive, are immediately up and running, and we then restore from the most recent snapshot in the background.

 

(2) initialize the new drive, install Mac OS X on it from your installer disk, install all updates to bring it up to current update level, install Retrospect, boot that drive, restore from most recent snapshot on top of that drive. For reasons that you may glimpse, it's important to have the same OS version and update level on the booted system that you are restoring on top of as in the snapshot that you are blasting on top of the running OS. That's the complexity of this part.

 

Emergency recovery is explained in the Retrospect manual. The manual is actually very good, and I suggest reading it. Reading it during a crisis, when your main computer has gone down, is really not the time for reflection and study. I suggest getting a spare drive and testing the emergency restore procedure, just so you understand it and have confidence in the procedure when (not if) you have to use it in a crisis.

 

Quote:

-When you say that the backup is on "our network," what do you mean by that? Isn't the data just stored on my drive...not a network?

 


I was referring to "our" network, not your setup, simply for comparison. Our law firm has an Xserve G5 that acts as our file server, our domain's primary MX (email server), our domain's primary DNS. We have a number of networked iMacs (and one PowerPC running Mac OS 9 for our billing system). Retrospect runs on the Xserve G5. Each night, after everyone has left, Retrospect walks around on our network, backs up all of the client computers on the network, shuts them down, then backs up the Xserve itself, all to tapes in our rack-mounted tape drive with autoloader (it's a little tricky to back up a live mail server - you have to shut down that service for a moment, copy the inactive mail store - Retrospect "duplicate" can be used, but we use "mailbfr" - then restart the mail server, then back up the mail store copy). We've also got a DAT drive that is not used except to read old Retrospect tapes from our archive from 1992 until we switched over to the Xserve. The autoloader switches between two backup sets on alternating days, and we take one set offsite.

 

Saved our butt when our floor of our office building burned down a couple of years ago on a Friday evening. We were back up and running in an alternate location, with new hardware, on Monday morning, thanks to our offsite Retrospect backups. If we ever accidentally delete a client's file and don't discover it until a few years later, we just retrieve the necessary file from backup. We never recycle / reuse our tapes.

 

Unrelated to this, our server has a RAID 5 array to handle disk failures, and we do a RAID 1 mirror split before making any changes to the server (software updates, etc.) in case things go bad, as they did one time.

 

So, you see, there are different strategies to handle different contingencies - file deletion, hardware failure, boot volume corruption/loss. It's all a matter of how valuable your data is, how long you can stand to be down, etc.

 

There's a good discussion of the issues/tradeoffs involved in backups here:

What should a good backup policy address?

 

Hope this helps,

 

Russ

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