Hi I am posting this in this area because I couldn't find a better place.
I am trying to make exact copies of my disk that I use in an old DEC3000.
I loaded the one disk then used dd
dd if=/dev/rrz0c of=/dev/rrz1c
I started this a 6pm last night here in Wales.
It is now 2pm the next day, that is approximately 20 hours.
This is an 18.2 GB scsi hard drive.
How long do you figure it will take to complete?
Is there an easier way or at least faster?
I was talking to one of my colleagues an he said oh it probably will transfer at 5MB a minute......that's about 1 day...is this right or is it longer?
The read/write led is on with both drives.
Seems to be working.
I used dd with an Ultra5 and ide disks using solaris and it only took about 4 hours.
Thanks for any help
Can you NFS mount the Solaris disk then move the data off of it, or simply leave it remote mounted. And access the data as needed.
My question is: if you've already copied the disk once why do it again?
The dd I used on the Ultra 5 was a different OS and application....Just wondering how long it will take to dd a 18GB HD.
Never thought of NFS.....I will wait till tomorrow morning to interrupt this dd if it is not finished. I will also check for a reply to this post.
Probably check for a reply before I hit the sack tonight......It has now been almost 24 hours....actually 23 to be exact.
Wished I knew what the transfer rate is.
Later, Mike
1645 10 May
I have some 20 GB IBM SCSI drive in my Sun SparcStation 20 (from 1994, so even newer than your DEC 3000) and it only gets off about 3 MB/s (dd if=/dev/... of=/dev/zero). You can generally speed up dd by using appropriate bs=... parameters (512, ..., 4069 are good values as they are typical inode sizes). By using count=... you can benchmark before doing the full task.
According to math rules at 5 MB/minute you'll have to wait two days.
Don't try this at a late stage, but for long transfers, it makes sense to try to benchmark the transfer rate before you start. Copy say one Gb and time that, just to be able to plan ahead.
Some versions of BSD-derived dd (I guess that would include Tru64) will give you interim throughput statistics when you hit ctrl-T but again, you might not want to try this on something which has already been running for very long.