We are going to upgrade/replace the storage for a customer with two AMS2100 systems with TrueCopy replication between them. One AMS2100 on the production site and one as a DR site. The replacement systems will be HUS110 with new disk trays. The new systems will be placed behind the AMS2100 so we can migrate the data from the old system to the new system.
The customer has a VMware vSphere environment with Windows and LINUX systems. The Windows systems are made with VMDKs so Storage vMotion will be used to migrate them to a new LUN (as datastore) on the HUS. The LINUX system have RDMs connected to them for database purposes.
I like to use TrueCopy replication for the migration of the RDM LUNs but I have some questions about it.
- First, it would be nice to replicate from one P-VOL to two different S-VOLs, but I think it is not possible? The option I have is to split the replication to the DR system (which is active right now) and then starting a new replication from the Original P-VOL to a new S-VOL on the new HUS110 system. The problem I have is that the replicated LUN is not on the DR site but on the same site as the production system. Is there a better way to do this? Maybe somebody has some good ideas ;-)
- My second question, do I have to upgrade the firmware of the AMS2100 systems before I can use TrueCopy replication to the HUS110?
- Can I just use the latest version of SNM2 and manage both systems for a short period (max 1 month)?
- The about the RAID groups. Is it possible to use TrueCopy to replicate between different types of RAID groups? Or do they have to be of the same type (RAID-5, 4D+1P)?
- What is the best RAID size to use when I have 20 disks. Is it better to have 4x RAID-5, 4D+1P then 2x RAID-6 (8D+2P) in performance perspective? In both situations I do not have a spare disk so I will try to have at least one disk extra for spare. Keep in mind that there are no HDP licenses. The customer just wanted the same as they have before and there was no budget for extra licenses (the AMS systems aren't that old).
- Any other tips for this kind of migration are welcome!
Thank you in advance.