Unsolved
This post is more than 5 years old
2 Intern
•
141 Posts
1
3025
VNX File - using LUNs from different Block Pools
Hello,
a customer of ours has a VNX Unified. Mostly for Block, with only a small amount of File storage. The File Pool only has about 2-3TB configured, all with LUNs from an existing Block Pool, which also has other LUNs used for general block storage.
Now they have just recently installed additional DAEs and disks, and want to create a new block pool dedicated for file. This new block pool will have the same disk types, capacities and tiers as the existing block pools (a mixture of 800GB Flash VP and 1.2TB SAS, all as RAID-5 (4+1) ).
There are 2 questions I have:
1) Can I use LUN migration to move the LUNs assigned to File from one block pool to another? Then afterwards I could create more LUNs in the new block pool to increase capacity for file. I know about https://support.emc.com/kb/464012
2) If I do not perform a LUN Migration, what would happen if I were to just add LUNs from the new Block pool to the ~filestorage Storage Group? So the ~filestorage group would then have LUNs from 2 separate Block Pools. Would the Mapped Pool 0 just increase in capacity, or would I get a new Mapped Pool 1 in Storage Pools for File? I have not got any hardware to test this out at the moment.
I have been trawling through documentation and the support site, but cannot find a definitive answer.
Thanks in advance.
Stephen
jcarrieri15
6 Posts
0
January 30th, 2017 11:00
Stephen,
I have the exact situation with my customer -- what was your resolution--I too would like to use LUN migration (However, I would be going from a Raid Group to a Storage Pool)
SteveK821
2 Intern
2 Intern
•
141 Posts
0
January 31st, 2017 08:00
Hi, I have an open Service Request with EMC asking for more information. From what I have heard back so far, adding LUNs from a different block pool would result in a new Mapped Pool for File. Then use File-System replication (RepV2) to copy the FS to the new pool. I've also asked if a LUN Migration is possible, but no answer yet.
I don't know how different it would be when going from RG to Pool. What do you see in Storage Pools for File? Do you have a mapped pool or something else? I think FS replication might be easier there.
jcarrieri15
6 Posts
0
January 31st, 2017 08:00
I actually got on the EMC VLAB and did LUN migrations from different storage pool layouts and Raid Groups and was able to migrate the File systems. However, I believe this would be something that would have to be done possibly offline, just because each underlining LUN that the FS is striped across needs to be migrated, because you can’t have a FS stripe across different File storage pools. I am testing if the FS stays online ans is accessible during the migrations. The LUN migration worked well and the VNX(2) did recognize the new storage pool structure after the migration. I did run the migrations from the GUI and from the Control Station using naviseccli commands against each LUN. After the migration I ran a “nas_diskmark –c –a” command to update the NAS database.
The VLAB is not perfect, but so far the LUN migration works very well. However, if the FS does not remain active during the LUN migration, I agree with you that Local FS replication may actually be a better choice
Thank you for your response, much appreciated—let me know if you get any feedback from EMC support ….
I’ll keep you posted as I continue testing
Joe Carrieri
National Pre-Sales Engineer/Sr. Solutions Architect
ePlus Technology, Inc.
4101 Cox Road
Glen Allen, VA 23060
804.837.9455 (mobile)
www.eplus.com
The information contained in this electronic transmission and any attachments hereto may be considered proprietary and confidential. Unauthorized distribution of this material to anyone other than the addressed is prohibited. Any disclosure, distribution or use of this transmission for any reason other than their intended purpose is prohibited.
SteveK821
2 Intern
2 Intern
•
141 Posts
0
March 3rd, 2017 03:00
Just to clarify, I managed to get hold of some test hardware and can confirm:
When you put LUNs from a different Block Pool in the ~filestorage group and rescan, then a NEW mapped pool is created under Storage Pools for File.
You can then use FS Replication (RepV2) to replicate the Filesystem to the new File Pool and switch it over. EMC support also recommended this way.
Some details are also here:
How to move a file system between different storage pools while keeping the exports and shares
So I tried that out, replicated a Filesystem to the new pool. Then I deleted the old FS after switchover and removed the LUNs from the first old pool:
nas_disk -list
to confirm that those disks were no longer in use, then:
nas_disk -delete [disknumber] -perm -unbind
As soon as the last disk from the old block pool was deleted from the NAS config, the Mapped Pool 0 disappeared from Storage Pools for File.
Rainer_EMC
8.6K Posts
0
March 3rd, 2017 04:00
thanks for the Feedback Stephen
yogad
78 Posts
0
April 5th, 2022 12:00
Whats an unmapped pool?. Is it possible to spread a file system across two different unmapped file pools?
DELL-Sam L
Moderator
Moderator
•
7.1K Posts
0
April 5th, 2022 15:00
Hello yogad,
In most cases unmapped pool is a pool that hasn’t been mapped to a host. It depends on the pools, but in most cases, you don’t want to spread a file system across multiple pools. Which vnx system do you have?