Blocksize with Ontape command

[netjc]

We are using a HP 230 Ultrium external tape drive to backup Informix data of 15 GB. While running the Informix command ontape -s -L 0, we get the error "Device does not support the blocksize. Archive failed -function open tape device \\tape0 failed code -1 errno -1". We have tried lowering the blocksize from 728 to 64. The backup works only at 64 but then takes hours to finish. Please help. Many thanks.

 

[cdlvj]

Did you try 512 or multiple (1024,2048)? Does the tape do ok with tar,cpio? What OS? On SCO, there is a tape command which there should be something on your system which gives you info about the device, allows you to set multiple defaults.

 

[netjc]

We tried 256, 512, 728 but the same error. The Operating system is Win 2000. If we backup with the Backup utility of Windows 2000, the backup is at high speed and finishes in less than 7 min. However, if we backup with Informix Ontape command, it can backup only at 64. Please help.

 

[cdlvj]

What flavor of Informix is this? ie version.
I do not see ontape mentioned in the docs for the NT version, as all they have is onBar.
Could it be that ontape is not supported?

 

[netjc]

The Informix version on Win 2000 is 7.31 TD8. We have also tried the Tape Drive on 2 Win NT servers with Informix version 7.31 TC6. On one server, Informix ontape backup takes place at 728, while on the other server, ontape backup will only take 256 or below.

We would appreciate if there is another way for the ontape command to accept a higher tape blocksize value.