topic Very slow while dumping remote tar to local tape drive in Operating System - HP-UX

Very slow while dumping remote tar to local tape drive

Bonny Jose_1 — Mon, 27 May 2002 07:49:18 GMT

Hi experts,
I am using following command to take backup of remote linux machine to the local HP-UX Dat drive.
#remsh linux1 "cd /home;tar -cvf - filename"|dd of=/dev/rmt/0m

Even though the command is working,It is very slow.If I copy the remote file to local hardisk it is very fast and also if I tar a local file to local dat drive it is fast.
I dont understand where will be the problem.
Could somebody help
Thanks
Bonny

Re: Very slow while dumping remote tar to local tape drive

Stefan Farrelly — Mon, 27 May 2002 07:55:49 GMT

There was a long discussion about the same thing recently. Read it all;

http://forums.itrc.hp.com/cm/QuestionAnswer/1,,0x1b7842308663d611abdb0090277a778c,00.html

Basically its to do with blocking/buffering over the network when using remote copies like this. Solution is in the above link.

Re: Very slow while dumping remote tar to local tape drive

Steve Steel — Mon, 27 May 2002 07:58:10 GMT

Hi

Try it the other way around as I always find it quicker

On the linux

tar cvf - filename | remsh hp -l user "cat - | dd of=/dev/rmt/0m bs=10k"

At least play with the bs of dd

Steve Steel