topic Re: bs option on dd copy command in Operating System - HP-UX

bs option on dd copy command

Joel Shank — Tue, 13 Dec 2005 09:34:43 GMT

I need to copy a large number of raw logical volumes from one device to another and plan on using dd. Does anyone know how the bs parameter effects the copy? How large can it be and what effect will a large value vs a small value have on the time it will take to copy the data? I know that the blksize must be a multiple of the device blksize and am assuming that this is the blksize on the filesystem (VxFS) that has been created on the device. Is that a correct assumption?

Thanks in advance for your assistance,
jls

Re: bs option on dd copy command

Robert-Jan Goossens_1 — Tue, 13 Dec 2005 09:45:32 GMT

Joe,

Here is a discussion about dd and the block size.

http://forums1.itrc.hp.com/service/forums/parseCurl.do?CURL=%2Fcm%2FQuestionAnswer%2F1%2C%2C0x464d5c7609e9d61190050090279cd0f9%2C00.html&admit=-682735245+1134485057349+28353475

Regards,
Robert-Jan

Re: bs option on dd copy command

Joel Shank — Tue, 13 Dec 2005 09:58:14 GMT

Thank you, Robert-Jan
That was exactly what I was looking for.

Can you tell me how you searched to get that answer? I tried searching 4 or 5 times and never got close to a answer that pertained to my question.

Thanks again,
jls

Re: bs option on dd copy command

James R. Ferguson — Tue, 13 Dec 2005 10:04:36 GMT

Hi Joel:

Use Google and limit your search domain to 'itrc.hp.com'.

Regards!

...JRF...

Re: bs option on dd copy command

Sยภเl Kย๓คг — Tue, 13 Dec 2005 10:06:13 GMT

Hi,
Search in itrc itself, with dd command as search string.

regards,
Sunil

Re: bs option on dd copy command

Joel Shank — Tue, 13 Dec 2005 14:01:36 GMT

Mischief managed.