Hi Thomas,
Unfortunately this is not an easy question to answer. Speeds can vary on any number of issues and the combinations of all those issues put together.
In your case, however, I can tell you the following: 1800MB/min is more than exceptional for a backup to tape. 550MB/min to firewire drives seems very good considering they are firewire drives and are probably IDE internally. 150MB/min seems slow simply due to the logic that your network backups are faster than the local backups to the same type drives. This could be because the local drive is very slow like a 5400 RPM drive, or that it's being taxed heavily. Maybe it's the only server on the network that does backups, Active Directory, Exchange, SQL, etc...??? I'm not sure what's on that server, so all I can do is speculate, but to answer your question, yes, logic, would dictate that 150MB/min is slow for that local backup. Normally you would expect it to be faster than the network backups.
Please let us know if this answers your question, and let us know of any other problems you might be encountering relating to this issue.
Thanks.
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