Windows服务的备份算法

Question

I have to design a backup algorithm for some files used by a Windows Service and I already have some ideas, but I would like to hear the opinion of the wiser ones, in order to try and improve what I have in mind.

The software that I am dealing with follows a client-server architecture.

• On the server side, we have a Windows Service that performs some tasks such as monitoring folders, etc, and it has several xml configuration files (around 10). These are the files that I want to backup.

• On the client side, the user has a graphical interface that allows him to modify these configuration files, although this shouldn't happen very often. Communication with the server are made using WCF.

So the config files might be modified remotely by the user, but the administrator might also modify them manually on the server (the windows service monitors these changes).

And for the moment, this is what I have in mind for the backup algorithm (quite simple though):

• When - backups will be performed in two situations:

  • Periodically : a parallel thread on the server application will perform a copy of the configuration files every XXXX months/weeks/whatever (configurable parameter). This is, it does not perform the backup each time the files are modified by user action, but only when the client app is launched.
  • Every time the user launches the client : every time the server detects that a user has launched the application, the server side will perform a backup.

• How :

  • There will be a folder named Backup on the Program Data folder of the Windows Service. There, each time a backup is performed, a sub-folder named BackupYYYYMMDDHHmm will be created, containing all the concerned files.
  • Maintenance : Backup folders won't be kept forever. Periodically, all of those older than XXXX weeks/months/year (configurable parameter) will be deleted. Alternatively, I might only maintain N backup sub-folders (configurable parameter). I still haven't chosen an option, but I think I'll go for the first one.

So, this is it. Comments are very welcome. Thanks!!

Answer 1

I think your design is viable. just a few comments:

1. do you need to back up to a separate place other than the server? I don't feel it's safe to back up important data on same server, and I would rather back them up to a separate disk (perhaps a network location)

2. you need to implement the monitoring/backup/retention/etc. by yourself, and it sounds complicated - how long do you wish to spend on this?

Personally i would use some simple trick to achieve the backup, for example, since the data are plain text files (xml format) and light, I might simply back them up to some source control system: make the folder a checkout of SVN (or some other means) and create a simple script that detects/checks in changes to SVN, and schedule the script to be executed once a few hours (or more often up to your needs, or can be triggered by your service/app on demand) - this way it eliminates the unnecessary copy of data (as it checks in changes only), and it's much more trackable as svn provides all the history.

hope above can help a bit...