drive mirroring

A

Avenue

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We take our hard drive home every day, and as a result have set up a mirrored drive in case something happens to the hard drive, like we drop it or something, then in theory we can just pick up where we left off without losing too much work.
Problem is the guy has set it up in such a way that it takes an hour to complete the mirror every day, and we cannot use the PC during that time. Is this normal? Is there no way to dynamically sync the hard drives while you are working so there isn't that down time every day?
We are using windows 7 pro.

edit* I found this tutorial, and this seems to imply that any changes should be automatically applied?
 
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This is an interesting challenge to say the least. Using a software mirror like the tutorial is okay as long as the machine is powered down for the entire time the one disk has been removed, otherwise it will detect an array degradation and when the disk is replaced, will remirror the data from the disk that stayed in the machine, effectively treating the disk as a new replacement of a failed disk. If the machine is off while the disk is gone and then started only after the disk has been replaced, the software won't notice.

Depending on how much data changes on the disk in a day, using rsync (there are a couple of Windows ports), to run a replication job would make more sense and could be extremely quick. It can be configured to only replicate changed files each time and might even be able to be run every 15/30 minutes to keep it up to date.

There is a commercial tool called Secure Copy, used to be by ScriptLogic, that is designed to assist with migrations of large file sets between Windows servers and maintain permissions etc. It can be configured to do changed-files-only replication and schedule tasks to do replication on a regular basis.

Hope these ideas help.
 
bruce_the_loon said:
This is an interesting challenge to say the least. Using a software mirror like the tutorial is okay as long as the machine is powered down for the entire time the one disk has been removed, otherwise it will detect an array degradation and when the disk is replaced, will remirror the data from the disk that stayed in the machine, effectively treating the disk as a new replacement of a failed disk. If the machine is off while the disk is gone and then started only after the disk has been replaced, the software won't notice.

Depending on how much data changes on the disk in a day, using rsync (there are a couple of Windows ports), to run a replication job would make more sense and could be extremely quick. It can be configured to only replicate changed files each time and might even be able to be run every 15/30 minutes to keep it up to date.

There is a commercial tool called Secure Copy, used to be by ScriptLogic, that is designed to assist with migrations of large file sets between Windows servers and maintain permissions etc. It can be configured to do changed-files-only replication and schedule tasks to do replication on a regular basis.

Hope these ideas help.
Click to expand...

Thank you that helps a lot!
 
ave said:
... Problem is the guy has set it up in such a way that it takes an hour to complete the mirror every day, and we cannot use the PC during that time. Is this normal? Is there no way to dynamically sync the hard drives while you are working so there isn't that down time every day?
We are using windows 7 pro.
Click to expand...
That smells a whole lot like a dumb (re)-copy of everything, every time. Which is, well, stupid - not everything changes all the time and if there's no change to a file (or part thereof), there's no good reason to recopy it.

What you want is some kind of a sync-scenario, in which only the deltas (changes) get copied and that *will* require an app to manage it as takes management/software to be able to track fine-grained details like that (exposition is for the benefit of posterity down the line). This can start with something as basic as SyncToy, with which jobs can be automated but not only are there many more apps (alternativeto, filters: Windows/free) but you can do better. And, riffing on ponder's input: look at DeltaCopy.
 
I used synctoy for quite a while. Worked good when I worked at three different places at a time (home, office and client). Had a PC at each location. Used synctoy with an external hard drive with the work on it. And before I leave or when I arrived I synced the drive.
 
Just run an xcopy or robocopy batch file to copy only changed files. Should take under a minute.

Open a command prompt.
robocopy /? will list all the parameters and switches.

You can use the built in scheduler to run your .cmd batch file at defined times.

You can easily check for the presence of a disk/directory/file with IFEXIST.
 
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