This post is more than 5 years old
4 Posts
0
859
July 2nd, 2014 05:00
SP assignment for LUN
Good Day,
Just wondering if someone can confirm the process for changing a Storage Processor on a LUN.
The only method that I see entails performing a LUN migration which would require creating new Destination LUN's where the original LUNs would be migrated to.
I would like to confirm if this is the only way of changing the Storage Processor that is assigned to a LUN.
If I change the Ownership from one SP to another, this would only apply when the storage system is powered up.
Thanks for your taking the time to look through my inquiry.
No Events found!
dynamox
9 Legend
•
20.4K Posts
1
July 2nd, 2014 14:00
for traditional RAID group LUNs ? yes you can just change the default owner and trespass. The trespass process is so fast your host will not notice a thing (that of course assumes that host is zoned properly and multipathing software is configured)
dynamox
9 Legend
•
20.4K Posts
1
July 2nd, 2014 08:00
for pool LUNs that is true, you must use LUN Migrator, for traditional raid group LUN you can change default owner and manually trespass the LUN.
asceticenergy
80 Posts
0
July 2nd, 2014 09:00
so for pool luns if I change the default owner from SPA to SPB it wont reflect ?
dynamox
9 Legend
•
20.4K Posts
1
July 2nd, 2014 09:00
if you look at properties of a pool lun you will notice "allocation owner" value. From what i understand from performance perspective while you could change default sp and tresspass the LUN ..you can't change allocation owner and that will have negative impact. So the recommended way to change SP is to create a new LUN on the SP you are interested in and then use LUN Migration.
asceticenergy
80 Posts
0
July 2nd, 2014 09:00
thanks dynamox :-)
ITGuy91
4 Posts
0
July 2nd, 2014 13:00
Thanks dynamox. I gather this would be the recommended approach then, to perform a LUN create on the SP we want to migrate to, then use LUN migration thereafter.
Do you know if I can alter the SP on a LUN without performing the LUN migration per the RAID group method you had mentioned? what impact would this have in regards to the process versus performing a LUN migration?
Thanks for your assistance on this.
ITGuy91
4 Posts
0
July 3rd, 2014 06:00
Again, thanks Dynamox for taking the time to answer my question. I had one last thing to clarify with you. According to the Navisphere Manager Admin Guide, in Section 14-9, they state the following;
Transferring default ownership of a LUN from one SP to another can
affect how the operating system accesses the LUN. Any change you
make in ownership does not take effect until the storage system is
powered down and up again.
So, if I change the ownership to another SP, would this not require the storage system to be powered down to take effect. I am trying to find a way to perform maintenance on an SP, while maintaining connectivity to the storage through the alternate, active SP that will be running while SP is in maintenance and powered down.
Thanks for your time and feedback.
dynamox
9 Legend
•
20.4K Posts
1
July 3rd, 2014 08:00
maybe they mean that if you do not manually trespass the LUN it will only take effect when you reboot the SP. That's crazy, i have trespassed LUN gazillion times on the fly without any issues (that of course assume second HBA/ zoning/path management software is functioning/licensed correctly)
ITGuy91
4 Posts
0
July 3rd, 2014 11:00
Thanks again for all your feedback dynamox, helped to clarify the matter.
Anonymous User
375 Posts
0
July 3rd, 2014 23:00
Transferring default ownership of a LUN from one SP to another can affect how the operating system accesses the LUN. Any change you make in ownership does not take effect until the storage system is powered down and up again.
That's not true....