01-08-2018 05:30 AM
Hi folks,
we will add an additional storage shelf to our 5240 Appliance (2.7.3). the new capacity will be used for expanding the MSDP.
if I remember correctly the underlying Storage Foundation has the possibility to re-layout the Subdisks to e.g. improve performance by (statistically) involving more controllers. E.g. by moving existing subdisks to some of the new disks to spread the load.
Now my question: Is it possible to do this with my appliance or are the appropriate commands not available?
Or is the system so intelligent that is does it on its own?
I couldn't find any information in the standard documentation.
Any help/suggestion/info is appreciated
Regards, Bert
01-08-2018 05:36 AM
01-08-2018 06:13 AM - edited 01-08-2018 06:15 AM
As the link eduncan shared says, the process of adding a storage shelf on an Appliance occurs using the Web Interface or the CLISH. I don't believe that there is much intelligence behind the operation in regards to performance tuning.
It is possible to modify the configuration using the commands from Storage Foundation in the elevated maintenance mode like you would a media server with a build your own MSDP pool. But I would have to guess that doing so would be under your own responsiblity, as you are making changes to the underlying OS which Veritas isn't keen on you doing.
We have used vxresize to fully allocate the available space to the MSDP partition, which is something that is difficult to manage using the CLISH without inadvertantly expanding the partition onto the base enclosure, where we keep the MSDP Catalog. That worked fine, but you do a lot of damage if your unlucky and risk not getting help from Veritas.
Caspar
01-08-2018 06:23 AM
As far as I know it is not supported to use underlying VxVM commands for this although they do exist. You can move Partitions but apart from the MSDPcatalog being "hot", I suspect the rest of MSDP I/O is likely to be fairly evenly distributed, at least once the Partition starts to fill up. BR Andrew
01-08-2018 06:53 AM - edited 01-08-2018 06:54 AM
See if these links help:
01-09-2018 08:06 AM
Thanks, folks, for your comments, I suspected as much :)
As the MDSP is already on expansion disk I will recommend doing nothing but add the shelf.
Regards,
Bert