Hello,

If I take a level 0 or 1 backup of my database does it include everything in my logical log backup tape? Do I need to keep the tape or can I rewrite on it without loosing any vital information? Also, is it imperative to re-run the continuous logical log backup everytime I backup my db?

thanks for any inputs.

nAtHaNs

A level archive contains all data (0) or changed pages from the higher level (1,2). So all logical logs earlier made are nor required anymore. There are some exceptions. If you make back-up with onbar and do this parallel (so without specifying the -w flag), then the logical log back-up is necessary to synchronize the seperate dbspaces.

Also if you save for example three level-0 backups, then you can overcome a bad media on the level-0 by going to the previous one and continue from there with logical logs.

It is not necessary to restart continuous log back-up after starting a level backup.

Hope this clarifies things a bit,

Rob Prop

Thanks for your reply Rob.

By the way I am using Level 0 online backup. Does it matter? When is the best time to change the logical back up tape?

Could you point me to some resources about how logical logs work.


Again thank you.


nAtHaNs

Nathans,

It doesn't matter the levelsyou make. If possible stick with the level 0 backup. When to change the logical log tape? Doesn't matter, of course before it is full. I always recommend changing at at regular intervals, for example once a week.

You can read the sysadmin guide at the IBM site (www.ibm.com/software/data/informix -> choose library) for more info.

Hope this helps,

Rob Prop

Rob,

Again thank you very much for your prompt reply.

More power.

Nathans.