On Friday 18 June 2004 6:56 pm, Matt Zimmerman wrote: > On Fri, Jun 18, 2004 at 04:42:43PM -0700, Brandon Darbro wrote: > > Huh? EVMS or LVM2 has a method of adding a writable layer to read only > > dasd? > > EVMS supports writable snapshots, using copy-on-write from an EVMS volume. > I haven't tried it with read-only DASD, but in theory it should be possible > for it to be used this way. The act of creating the snapshot might require > writing to the original volume in order to update the volume metadata.
EVMS can take snapshots of read-only disk partitions. It doesn't ever write any metadata to the origin volume when a snapshot is created. All the metadata is stored on the snapshot object. However, it won't work with whole disks. As I explained in an earlier post today, we can only take snapshots of DM devices. Whole disks (and RAID-1 and RAID-5 from the MD driver) cannot be snapshotted in EVMS. However, since your disk is read-only, you could manually create a snapshot using dmsetup. Let me know which (if any) of these options would work best for you and I'll provide more details. -- Kevin Corry [EMAIL PROTECTED] http://evms.sourceforge.net/ ---------------------------------------------------------------------- For LINUX-390 subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390
