Re: Server 2003 - NTBackup not compressing files to tape


"Donald Campbell" <Donald@xxxxxxxxxxxx> wrote in message
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In article <#l$d4bxdIHA.1824@xxxxxxxxxxxxxxxxxxxx>, "Pegasus (MVP)"
<I.can@xxxxxxxxxx> writes

"Donald Campbell" <Donald@xxxxxxxxxxxx> wrote in message
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In article <#ONzmKxdIHA.4144@xxxxxxxxxxxxxxxxxxxx>, "Pegasus (MVP)"
<I.can@xxxxxxxxxx> writes

"Donald Campbell" <Donald@xxxxxxxxxxxx> wrote in message
news:IcdGCdIJJbwHFAG5@xxxxxxxxxxxxxxxxxxxxxxxx

Backing up to DDS tape.

Compression is enabled on the drive, but when NTBackup runs it only
puts
on the native amount before asking for a second tape.

NTBackup is told to use compression if possible.

Any ideas (apart from don't use NTBackup).


Don


The key is in the phrase "use compression if possible". I suspect
that your backup drive does NOT offer hardware compression.
Many manufacturers state a tape capacity of 20/40 GBytes
(uncompressed/compressed) (for example) but fail to state that
this refers to ***software*** compression. I consider this
misleading.

In other words, unless your tape drive has inbuilt hardware
compression, you're stuck with the lower capacity figure.




Looking at the Windows "hardware" set-up the driver for the tape states
"compression enabled".

HP diagnostics indicates that the drive is fine.


Don


Rather than relying on what the driver says, I would check the
manufacturer's data ***.



Diagnostics says that it can and the spec says that it does.

Don

In this case I would do this:
1. Post the exact ntbackup command line here so that someone
can confirm that hardware compression is turned on.
2. Armed with this confirmation, complain to HP.


.