Tape ejects as full when whole tape has not been filled

[Richard_Lian]

We are using a hp/compaq AIT-1 drive and AIT-1 35/70Gb tapes. When i run a full backup of around 44Gb it ejects the tape at around 43Gb and asks for another. I cannot seem to figure out why this happens. I have full overwrite enabled and no append. I have tried using hardware and software commpression and it makes no difference. Any ideas?
Thanks

[Deepali_Badave]

Hello,

This issue may occur if certain media related alerts generated during the backup operation are not responded. Please verify the same.

This will also happen if overwrite protection is set with the option "NONE"
- advised data could also be near capcity of the tape
- advised to change the following settings
1. set Tools|Options|Media Overwrite to "Partial" without Prompt
2. set proper overwrite protection time in Media Sets according to tape rotation requirements.

-- Also refer the following technote:

Backups fail to get double the amount of the native capacity recorded to a media, even when hardware compression is being utilized.]
http://seer.support.veritas.com/docs/199542.htm
You may try out the compression attained using Windows NTbackup utility and compare the same with the compression attained with Backup Exec .

NOTE : If we do not receive your reply within two business days, this post would be marked assumed answered and would be moved to answered questions pool