Very Computer

I have a node on a fairly large installation that has been handed down
from admin to admin over the years.  This particular node is a
production node that can not have down time while I am trying to fix a
rather serious problem with bad mirror design.

I like to mirror front to back in my drawer...so the hdisk1 would be
mirrored to hdisk 9.  Well, there are 3 hdisks in the chasis, so its
actually hdisk3 to hdisk11.

The problem I have, is that the previous admins mirrored any way they
wanted too -- 3 to 17 ..oposite side of the drawer, or worse yet, 3 to 4
-- both on the same loop.

How I have been fixing this, is by creating a third copy of the LV,
deleting the "bad" one, then moving the data to its new
home...basically, a shell game.  (No down time -- just a performance hit
while the copys are taking place)

This works well -- but it is VERY difficult to keep the LV's straight.

Are there any applications that will do this graphically?  I can get a
picutre of the loops, but not so far down as the file system or LV.

Thanks in advance...

-Gerry

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As far as I know, there is no graphical program, but I have had occasion to
do this, and I find that maymap, combined with something like:

for i in `lsvg`
do
  lsvg $i
  lsvg -p $i
  lsvg -l $i
done

 comes in handy.  Other than that, under 4.3.3-02? (maybe 03), there is a
new undocumented command replacepv - you can take a PV not belonging to a
VG, and make it replace an existing PV in a VG - common sense says to use
the same size drive,and the replacepv command effectively avoids the
tertiary copy, add and remove problem entirely.

I have used it with no problems (including PV having paging space lv's) ,
but I suggest you call AIX support and check for your particular
circumstances.....

-Dan

Diag -> service aids -> ssa
will give you the serial numbers on ssa disk. Also will show you
whats on what loop.
I don't know how to get an output from diag to a file so I just
copy and paste this info. I wrote a perl script that converts the
pdisk designation to the hdisk. But this is still all text.

Quote:> > I have a node on a fairly large installation that has been handed
down
> > from admin to admin over the years.  This particular node is a
> > production node that can not have down time while I am trying to fix
a
> > rather serious problem with bad mirror design.

> > I like to mirror front to back in my drawer...so the hdisk1 would be
> > mirrored to hdisk 9.  Well, there are 3 hdisks in the chasis, so its
> > actually hdisk3 to hdisk11.

> > The problem I have, is that the previous admins mirrored any way
they
> > wanted too -- 3 to 17 ..oposite side of the drawer, or worse yet, 3
to 4
> > -- both on the same loop.

> > How I have been fixing this, is by creating a third copy of the LV,
> > deleting the "bad" one, then moving the data to its new
> > home...basically, a shell game.  (No down time -- just a performance
hit
> > while the copys are taking place)

> > This works well -- but it is VERY difficult to keep the LV's
straight.

> > Are there any applications that will do this graphically?  I can get
a
> > picutre of the loops, but not so far down as the file system or LV.

> > Thanks in advance...

> > -Gerry

> > Sent via Deja.com http://www.deja.com/
> > Before you buy.

Sent via Deja.com http://www.deja.com/
Before you buy.

Quote:> > I have a node on a fairly large installation that has been handed
down
> > from admin to admin over the years.  This particular node is a
> > production node that can not have down time while I am trying to fix
a
> > rather serious problem with bad mirror design.

> > I like to mirror front to back in my drawer...so the hdisk1 would be
> > mirrored to hdisk 9.  Well, there are 3 hdisks in the chasis, so its
> > actually hdisk3 to hdisk11.

> > The problem I have, is that the previous admins mirrored any way
they
> > wanted too -- 3 to 17 ..oposite side of the drawer, or worse yet, 3
to 4
> > -- both on the same loop.

> > How I have been fixing this, is by creating a third copy of the LV,
> > deleting the "bad" one, then moving the data to its new
> > home...basically, a shell game.  (No down time -- just a performance
hit
> > while the copys are taking place)

> > This works well -- but it is VERY difficult to keep the LV's
straight.

> > Are there any applications that will do this graphically?  I can get
a
> > picutre of the loops, but not so far down as the file system or LV.

> > Thanks in advance...

> > -Gerry

> > Sent via Deja.com http://www.deja.com/
> > Before you buy.

--
replacepv is included in the online documentation I received with my AIX
4.3.3 level system.

Richard Snow
Telleo

Sent via Deja.com http://www.deja.com/
Before you buy.