question

yossim avatar image
yossim asked

Differential and full backup lsn not match

Hi, I have a maintenance plan that do a full backup one a week and diff backup every day. I noticed that the lsn is not match between the last differential and the last full. I don't understand how the last diff backups not match the last full backup? For some reason it match the one before the last full backup. The print screen that I attached come from query msdb.backupset and msdb.backupmediafamily Thanks ![alt text][1] [1]: /storage/temp/1727-backuphistory.png
backupdifferential-backuplsn missing
backuphistory.png (54.5 KiB)
10 |1200

Up to 2 attachments (including images) can be used with a maximum of 512.0 KiB each and 1.0 MiB total.

1 Answer

·
DenisT avatar image
DenisT answered
This is a normal behavior! There is nothing wrong with the picture. Before a FULL backup is taken, SQL issues a checkpoint which becomes the first LSN and since it's a first LSN each DIFF backup has to include it. If you look at the picture, each FULL backup concludes the chain. You can run the came query but add checkpoint_lsn and first_lsn columns to it. You'll see what I am taking about.
1 comment
10 |1200

Up to 2 attachments (including images) can be used with a maximum of 512.0 KiB each and 1.0 MiB total.

Thanks for your answer. I added [checkpoint_lsn] column and now all is clear. :)
0 Likes 0 ·

Write an Answer

Hint: Notify or tag a user in this post by typing @username.

Up to 2 attachments (including images) can be used with a maximum of 512.0 KiB each and 1.0 MiB total.