Adding New Member to Group

Question

Hi,

I am fairly new to the EqualLogic arrays. We have just received our second array (PS4100e) and we want to add it to our existing one. I am pretty sure after reading a few things I can add it to the "group" but my question is when adding it to the group will that cause the existing data to have any downtime? I am just wondering if I can do this early in the a.m. when a few users might be on the system and if they would notice anything.

Also if there are any links to any reading material on adding to a group/best practices that would be great. Would love to read everything I can before doing this.

Thanks in advance!!

Origin3k · Answer

There is no downtime or interruption!

But if you place your new EQL into the pool with the existing one the volumes will automaticly span over both members because this is the default setting of the group. You can change this behaviour by disabling it or if you like create a new pool and place the member in. Balancing the volumes over membery gives a nice performance boost but if you lost one member all the data is gone (like Network RAID0).

Best practice is to greate a new pool to place the member in, let him finishing the raid creation, creating small test volume, and ping all ports from the hosts so that you can be sure that your iSCSI swtich is configurated in the right manner. Now move it into the existing one.

Regards,

Joerg

inflxx-ec · Answer

Our switches are stacked. So we should be all set.

I guess the only other question I have is in VMware do i need to add 2 more ISCSI connections now that I will have 4 total ports active (2 for the 1st ps4100, 2 for the 2nd ps4100)? And then map them to the specific VMnics? So my vSwitch will have ISCSI01 - 172.16.0.x, ISCSI02 - 172.16.0.x, ISCSI03 - 172.16.0.x, ISCSI04 - 172.16.0.x?

Thanks.

inflxx-ec · Answer

I was referring to Physical Switches. I guess my main question is now is once the new PS is in the group do i have to change anything on the VMware side? I can't seem to find any info on that. Thanks.

inflxx-ec · Answer

So do I leave everything the way it is and just connect the new PS4100 to the switches? Will VMware detect any new paths?

Origin3k · Answer

You dont need to change anything on the VMware site.

I dont see the need to increase the number of VMKs and pNICs from 2 up to 4 in your case. But if you have SANHQ up and running you can take a look to your used network bandwith. The VMware swISCSI initiator use the EQL Group IP (WKA "Well Known Address") and will be automatic redirected to the eth ports. So it will "learn" the new address without any help from the admin.

Check if you have EQL MeM 1.1.2 installed on your VMware hosts.

Btw. your new EQL need 2 iSCSI address and one Management. Later one is optional and isnt use from the ESXi Hosts.

Regards,

Joerg

inflxx-ec · Answer

Ok, great. I wasn't sure if I had to change anything on the VMware side. I am guessing I will still need to give the new Member 2 new IPs.

If I create a new pool and wait till the raidset is finished what type of impact is it on the array when I merge the two pools?

EqualLogic

Adding New Member to Group

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