syncronized backup

Hi

We have 2 different systems that exchanges quite alot of information, both ways. but his creates some problems when it comes to backup, if one system crashes and needs to recover it will be in a state which is not syncronized to the other system. Even if we restores both databases it is hard to make sure they were in perfect sync. Both the system is 24/7 so take them offline for backup is not my first choice...

Anyone has any experiance with a situation like this?

/johan

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