Major MS Exchange issue. Need to ensure a good backup is peformed

We had a major 2007 Exchange issue.  One of our CCR nodes failed, and now we are running the Cluster with only one node. 

Therefore we are having an issue with Truncation of the log files.

This coming weekend we hope to bring up the node, and get the cluster back online.  However before we do so we want to make sure our backup is good.

Currently we Backup Exec 12.5 do a full backup every night of the Information Stores, but not the log files.  Are those log file folder necessary to backup incase we have a major failure and need to restore from tape?

We have another system doing the system state backup.

See screen capture below to see our selection list.

Thanks for the help!

-Evan

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