veritas problem

[karan_3]

hi,
We are using veritas volume manager 3.5. actually i am confuse with term plex and volume.i want to know . if everything(raid layout) can be done at plex level then why we have to make the volume of that plex.

[Florian Heigl (new acc)]

after reading the whole veritas manuals I also still was confused as to where the advantages of this concept were.
(NOT talking of raid5, and all the features, but the additional layers vxvm uses)

After working with LSM (which is just veritas by all I can tell) on Tru64 and SDS on Solaris I finally figured out - these operating systems still use multiple slices on disks and the plex-disk-volume thing is to integrate vxvm features into these OSes.
(Or at least this is what I think)

[Kent Ostby]

A plex is essentially a group of physical extents.

A volume is a group of logical extents.

If you are not mirroring your VOLUME then you will only have one PLEX.

If you are mirroring your VOLUME, you will have multiple PLEXS.

If you are familiar with LVM, a volume is essentially equivilant to an lvol.

A plex is essentially equivilant to one copy of the lvol.

[karan_3]

i got my answer