RA8000 change to multibuscopy

[Rocky_8]

Hello,

I have a question for the digital techies,

I want to upgrade a Raid Array 8000 with hsg80 controllers running in Transparent failover attached to a single 16 port switch.
Upgrade will go to redundant paths using 2 hba's + secure path and two switches.
The hsg80 pair needs to be migrated to multibuscopy in the smoothest manner possible.
Obviously a "set this_controller nofailover" followed by "set this copy=multibus" (or something in that area, its been a while) is the way to go.
But what possible glitches can i expect, or are there tricks/tips ?
I cannot risk dataloss or problems with raid sets.

Any tips are very helpfull, in preperation of this migration.

Thank you in advance,

Rmk

[Uwe Zessin]

Hello Rocky,

remember that in transparent failover Units 0/1..99 are presented through controller Port_1 and 100/101..199 are presented through controller Port_2. That is hard-coded in the controller and you should see that the connection for Port_2 has a UNIT_OFFSET of 100.

When you set NOFAILOVER, if I remember correctly, the OTHER_CONTROLLER automatically shuts down. Obviously somebody must be present to press the RESTART button.

After the change to MULTIBUS you get additional connections where you need to check the UNIT_OFFSET and OPERATING_SYSTEM. It is a good idea to add them to the correct units as well ;-)

You might want to move some units into the < 100 range. That can be easily done by deleting the unit, then:
> add unit Dn sset DISABLE_ACCESS_PATH=ALL
> set Dn ENABLE_ACCESS_PATH=(con1,con2,...)

Do a SHOW everything before you start. Make sure you don't have any reduced or rebuilding storage sets before you delete any units.

[Rocky_8]

Uwe,

Ah yes i remmember the offsets, good tip.
Is it not true that both controllers in a multibuscopy see units 1-199 ?
what will the impact be on my server machines, where on some of them SAP and Exch is running, when deleting and adding the units on my hsg80 ?

thanks again,

rmk

[Uwe Zessin]

That's correct. In multibus failover mode all units (0/1..199) are presented through all 4 controller ports. I think it should not have any effect as long as you don't try to reinitialize any storage sets. The windows signature is kept and the LUN WWN is kept in the storage set's meta data area.

On the other hand, you can modify the UNIT_OFFSETS for the new connections and thus even keep the LUN addresses that the server sees.