Daylight saving/summer time - Retrospect now thinks all files have changed!

[randm]

Recently daylight saving or summer time was started and our macs use Apple - asia to update time. Apple-asia got it wrong and were using the older start date so I updated the time manually on the machine running Retrospect and those in the rest of the studio, but did not do the same on the file server - doh! ( that's a long story....). I now find that Retrospect wants to back up all the server (read about $1000 in tapes!!) instead of just new and changed files. Anyone got any ideas about how to get out of this bind or am I up a creek in a barbed wire canoe here like I suspect?

[twickland]

You don't say what kind of computer you're using for your file server. If all computers are Macs and you have set them all to the same time zone and clock time, you shouldn't experience this problem. If, however, the server is Windows, you have three sub-optimal options: back it up using a Windows machine, set it to the wrong time zone, or live with the need to back up everything again at the seasonal time change.

 

We endure the third option, using each time change as the point where we perform either a new media backup or a recycle backup.

[ullistrator]

There's a fourth way I once had to figure out:

 

- Write down the selectors your script uses currently (or simply do a "Save as" from the Selectors menu).

- Go look when the last backup was run. [Configure > Backup Sets > "Name of your Set" > Configure > Snapshots > Now search for the most recent entry (Good luck: the list is usually cluttered and-even worse-isn't sortable!) ]

- Write a selector which chooses only those files with a date of change that lies after the last backup date: «File modification date and time is on or after fixed date (your date, your time) no offset».

- You can test the selector with cmd-T.

- Change the backup script to use the newly created selector.

- Run the changed script once.

- Change the selector back to those ones used previously.

 

Done. About $1000 in tapes saved.

 

edit

Explanation:

With the normal way of backing up Retro sees gazillions of files with a mod date differing from it's database's entries. By using the new selector you instruct Retro to really only backup files that have a mod date greater than/equal to the one in its database and not also these that were "changed" before the last backup.

 

After running a complete backup with the new selector Retro has it's database updated to the new situation, so you can now set back the selector to the previous ones.