I am currently using a NetApp v6280 cluster connected to a HDS storage system via a Fabric. How can I make all the backend paths to the storage system be Active/Active? Currently the system is treating them as Active/Passive and thus potentially using only half the paths. The V-series best practices guide points out this path information as well and I am wondering if there's a way to fix this?
v6280-top> storage array show-config
LUN Group Array Name Array Target Ports Switch Port Initiator
Group 0 (18 LUNS) HITACHI_DF600F_1 50:06:0e:80:10:13:8c:22 bs32_testbed1:29 0d
50:06:0e:80:10:13:8c:2a BS33_testbed2:23 0b
Group 1 (22 LUNS) HITACHI_DF600F_1 50:06:0e:80:10:13:8c:28 bs32_testbed1:31 0c
50:06:0e:80:10:13:8c:20 BS33_testbed2:22 0a
v6280-top> storage load summary
Port Total Load Switch Array Port #Blocks Array LUN Count
0c 50% bs32_testbed1:32 50060e8010138c28 1127 22
0d 49% bs32_testbed1:33 50060e8010138c22 1091 18
0a 0% BS33_testbed2:32 50060e8010138c20 0 22
0b 0% BS33_testbed2:35 50060e8010138c2a 0 18
As you could see above, the array target ports ending with 8c:22/2a and 8c:28/20 are the redundant paths. But all the I/O ends up in just one of the paths to the LUN. Appreciate your feedback. Cheers!
DataONTAP will prefer the paths the arrays tells it to. Unless the array is an active/active array, only the paths to one array controller will be active. If the array is active/active, and the paths are therefore equal, then DataONTAP will split the LUN access across both paths.
When running DataONTAP 8.1 and later in Cluster Mode, you are able to use 4 paths per array LUN group. This allows you to have 2 path to the active controller in on an active/passive controller. Or all 4 on an active/active array.
In your case, ensure that your AMS is running in symmetric active/active multipathing mode, and you should then observe a fairly equal # of array LUNs being accessed on both available paths.
Thanks Dan for the response and feedback. You mentioned "ensure that your AMS is running in symmetric active/active multipathing mode". Is there a specific setting in the AMS that needs to be changed to reflect this mode? If yes, could you please give more details? Thank you again!