Backing up using Windows File History Backup

Started by Canay, March 15, 2016, 03:29:11 AM

Previous topic - Next topic

Canay

I needed to restore my database today. Without getting into the why of it because I don't know (it might have had something with Windows shutting down suddenly and installing Windows 10 without me asking it to) I thought it was no problem because I have three different backups of my data base. (Or so I thought). My first source was Crashplan where I unfortunately realized was only backing up my D drive. At some point after I got Windows 8 and had two drives, I moved my database to the C drive based on something I read here. That worked fine but I didn't think about needing to add that folder into my Crashplan backup. No problem, I moved to my next backup source Windows File History Backup. I found the folder but each backup had three files to it and I had no idea how to restore from these three different files. I tried searching for solutions to this but I couldn't find any answers. I was able to restore my database from my pack and go backup and all is fine now. But...I'm wondering for the future what the three files are in Windows File History Backup and how I could have used them. Attached is a screen shot.

Not an urgent question at this point but I'm curious why the database just didn't copy over to the file history backup like all my other files do.

Thanks for any insight.

Canay



[attachment deleted by admin]

Mario

It would have helped if you just listed the file names with extension, not just posting a screen shot with all the important information hidden.

It seems that your backup procedure backs up open IMatch databases. IMatch creates temporary files, journaling logs and other temporary elements while a database is open in IMatch.

A database should only be backed up when it is closed, and in that case you only have the single .IMD5 file which contains everything.

If your backup solution backs up open IMatch databases at some arbitrary point, you need to make sure to restore all the files.
When IMatch opens the database the next time, it detects the WAL and other files. The database system then assumes that IMatch has not been properly shut-down and starts a rollback/recovery operation of the database, rolling back all incomplete and open transactions to ensure that the database is in a healthy state.
-- Mario
IMatch Developer
Forum Administrator
http://www.photools.com  -  Contact & Support - Follow me on 𝕏 - Like photools.com on Facebook

Canay

Thanks Mario. I had originally typed the names with the extensions, then decided a screen shot would be better. Sorry.

I have no idea at what point file system backup is doing the backups. I appreciate the explanation about backing up the open data base. At least that makes sense to me. I obviously should be more knowledgeable about my system. It seems that ever since Windows 8, I have become a user of a few programs and I no longer have an in depth knowledge about my program. I think it would be in my best interest to research a little about file restore and know what it is doing. But thanks to the advice I've received here, I don't rely on one backup and that has saved me a couple of times.

Thanks for all your support. Have a great day!

Mario

Windows has features (volume shadow copy) which enables backup applications to take a consistent snap-shot of the file system. This makes tools like Acronis TrueImage, Macrium Reflect etc. possible, which don't backup files, but entire disks. At a later point the restored snap-shot can be restored, restoring the file system exactly into the backed up state. This is really great for backups.

If an 'open' (in action) IMatch database is backed up and restored that way, the temporary files will be detected by IMatch during the next start. For IMatch the situation is then the same as when the computer had crashed (or IMatch  :o ) IMatch instructs the database system to bring the database back into a consistent  state, rolling back incomplete transactions (if there are any) etc. This is per-sé not a problem, it's part of the design. It will not harm your database.

Problems can occur when a user backs up an open database, but then later decides to restore only the .IMD5 file, without the other files. This can break things, because the database will know that it has been not properly closed the last time, but it cannot find the temporary files it needs to do a proper rollback.

This is not a typical IMatch problem, it's the same with all database systems, server applications and suchlike. As long as your backup application uses 'imaging' technologies (Windows does) you should be safe. Doing backups every day and keeping them for a couple of weeks is the important part  ;)
-- Mario
IMatch Developer
Forum Administrator
http://www.photools.com  -  Contact & Support - Follow me on 𝕏 - Like photools.com on Facebook