SUMMARY: disk-to-disk copy

From: Risto Tolonen (kiva!risto@snowbird.Central.Sun.COM)
Date: Tue Aug 11 1992 - 21:18:17 CDT

Here's a late summary for my question on "disk mirroring" ..

> Does anyone have an elegant solution to mirror a disk without the benefit of
> an 8mm tape drive? Would something like this work:
        [ additional junk deleted ... ]

Two types of answers due to my failure to use the correct terminology i.e. my
question referred to disk-to-disk copying rather than actual disk mirroring:

1. Use Sun's Desk Suite software for actual mirroring. Additionally,
   public domain "abcd" (Automatic Backup Copy Daemon, consult archie
   for the nearest copy) can be used for making copies of files changed
   on file base.

2. To copy disk-to-disk you can use two different methods.

     a) # dd if=/dev/sd1a of=/dev/sd2a bs=n
                    ( heads x cyls ) x sec/trk
        where n = -------------------------- for speed's sake ...

        will result into a perfect mirror copy with the boot block intact.
        However, this method will only work if the disk geometries are

    b) # dump 0bsdf 126 6000 54000 - /dev/rst1a | (cd /mnt; restore rvbf 126 -)

        where the target partition is mounted to /mnt. This will copy the disk
        even if the partitions are not identical. In order to make this
        partition bootable you must install the boot block. For further info
        on the boot block install refer to the man page for 'installboot'.

Also, I wanted to apologize for the bogus reply address and
thank the people who pointed it out for me.

Thanks to: (Neil Bennet)
snowbird!!scheller (Mark Scheller x6519) (Chuck Malmsten)
mks! (Andy Toy) (Dan Kelley)
bernards@ECN.NL (Marcel Bernards)
bit!jayl@Sun.COM (Jay Lessert) (Rand S. Huntzinger)
Mike Raffety <>

This archive was generated by hypermail 2.1.2 : Fri Sep 28 2001 - 23:06:46 CDT