Serviceguard

need HELP moving to a new storage!

 
loy4lplay
Occasional Advisor

need HELP moving to a new storage!

We're moving our data to a new EMC storage, I would appreciate it if someone validates my step-by-step guide as I plan on doing this sometime this week, again, help will be extremely appreciated!

 

SEE ATTACHED FILE

5 REPLIES 5
Ruel Alojado
Advisor

Re: need HELP moving to a new storage!

In migrating /dev/vggirdatos, you have already 18 PVs, the maximum PVs for this VG is only 30. 


You will have a tough time on this VG as each LV's uses 18PV's also.

 

Goodluck!

loy4lplay
Occasional Advisor

Re: need HELP moving to a new storage!

what can be done with that VG then?

Bill Hassell
Honored Contributor

Re: need HELP moving to a new storage!

As you are seeing, small LUNs (PVs) can be difficult to manage. The VGs were all created with smallest extent size (4 MB) which is a big problem for the future. These should have been 16 MB or 32 MB in size and the maximum number of extents per PV should not be defaulted but increased to 20,000 or 30,000 so much larger LUNs (PVs) could be added. The original creation of the VGs did not allow for expansion, and because this is 11.11, modifying some of the VG parameters is not possible.

So for the problem VG, you'll have to create a new one using just the new storage.  Triple or quadruple the size of the LUNs for this VG, then use vgcreate with -s 32, -p 50 and -e 30000. That way, you'll have plenty of room on this VG for future expansion. You'll then have to copy all the data from the old VG to the new one. Once copied, you can export the original and copied VG, then reimport the new one using the old VG name.

 

Yes, this will require downtime so that the data doesn't change during the copy period.



Bill Hassell, sysadmin
loy4lplay
Occasional Advisor

Re: need HELP moving to a new storage!

Bill see attached TXT

Bill Hassell
Honored Contributor

Re: need HELP moving to a new storage!

 

This VG is 27776Mb in size. For the new VG, do I present a single 277776Mb LUN?
I would vgcreate -s 32 -p 50 and -e 30000 vggirarchvmax

Rather than create a single LUN, I would create 3 LUNs, each 10 GB in size. Then you can add additional 10 GB LUNs if needed.

With 10 GB LUNs, you don't need to use -p 50, perhaps -p 20.  Same with your other VGs.

 

You can create the VGs and then copy the data from the shared VG to the new one.

The original goal was just to change storage, but the limitations of some VGs prevents in-place data mirroring.

So there are a lot of steps that will need to be documented along with a lot of details about the two packages and the time required for the data copies. This is a fairly large project that will need some planning.



Bill Hassell, sysadmin