ONTAP Hardware

Active/Active backend paths

GRANGARAJAN1

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!

1 ACCEPTED SOLUTION

isaacs

Hi Gokula,

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 Isaacs

isaacs@netapp.com

View solution in original post

5 REPLIES 5

isaacs

Hi Gokula,

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 Isaacs

isaacs@netapp.com

View solution in original post

olgac

Hi Daniel,

What is the biggest speed that one path can work? Does It depend on what?

Thanks.

Olga.

isaacs

Hi Olga,

We can run on 8Gbps Fibre Channel.  That's is currently the highest bandwidth initiator we support.

Thanks!

GRANGARAJAN1

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!

isaacs

Unfortunately, I do not have much experience with the newer AMS models.  You should be able to contact HDS support and get an answer.

Good luck!

Announcements
NetApp on Discord Image

We're on Discord, are you?

Live Chat, Watch Parties, and More!

Explore Banner

Meet Explore, NetApp’s digital sales platform

Engage digitally throughout the sales process, from product discovery to configuration, and handle all your post-purchase needs.

NetApp Insights to Action
I2A Banner
Public