Legacy HDS Forums

AMS2500 TCE with VMWare SRM and consistency group problem

Discussion created by Legacy HDS Forums on Feb 17, 2011

Originally posted by: grzegorz.masal


I'm implementing VMWare SRM with AMS2500 and TCE.
I have two data centers and both are running as primary and recovery sites for different appliactions on VMWare servers. So In first center I have 20 guest OS and each have one volume. Same situation in second center.
I want to replicate this 20 volumes from first center to second and next 20 from second to first. All using TCE.
I also want to user SRM and I want to have possibility to switch with SRM only one volume and set reverse replication (for example) from first center to second. All other 19 volumes will stay in primary center with replication to second data  center.
I set up 2 sets of horcm services and files. One pair for replication from first data center to second and another pair files and services for replication from second center to first.
I know that in horcm files for one direction I must create 20 groups in  HORCM_LDEV section. Each group for one pair of volumes.
Later I create TCE pairs with paircreate command. For each pair I must use -fence async switch.
If I use paircreate -g VG1 -c 7 -vl -fence async pair will be created in new consistency group (for example 0) and later when I use
paircreate -g VG2 -c 7 -vl -fence async pair will be created in consistency group 1 and so on.
If I use paircreate -g VG3 -c 7 -vl -fence async 0 pair will be added to consistency group 0

After making 16 pairs I'm running out of consistency groups which are 16 in AMS2500 (and 16 consistency groups are for two arrays for both directions)  and I'm stil preparing replication for one direction.

Of course I can put two groups (for example) VG1 and VG2 into one consistency group but if I use SRM on VG1 group and SRA will takover S-VOL from VG1 group it also same will be done on volume from VG2 because they are in same consistency group.
So my question is: IS it possible to create TCE pair without putting it into consistency group or maybe there is specail way to configure SRA for such configurations as above???
For me it is strange that if I must put each TCE pair into consistency group and on AMS2500 I can create more than 4000 TCE pairs in only 16 consistency groups

Any help will be very usefull for me

Regards Grzegorz.