You are correct that clustering is treated as two separate controllers which can take over for each other. You cannot vif across NICs on different controllers.
If you want to do the closest thing to active/passive would be to allocate at least 2 (possible 3 if you want a spare) disks to the "passive" controller and the rest to the active one. I'd set up a raid4 trad vol or aggregate for it since you only are going to use 2 disks, you don't need raid_dp. Definitely use raid_dp on the active controller.
Under this scenario, you can lose either controller head and still be running.
-- Adam Fox Systems Engineer adamfox@netapp.com
-----Original Message----- From: Ray Van Dolson [mailto:rvandolson@esri.com] Sent: Tuesday, June 02, 2009 11:44 AM To: toasters@mathworks.com Subject: FAS2050C questions (clustering)
I'm the proud new owner of an IBM N3600 A20 (rebranded FAS2050C) with 20x30GB SAS disks.
I'm trying to determine the best way to get this thing set up, and realized I have only a bit of a fuzzy understanding as to how the clustering or failover filer head should work.
My initial thoughts were to aim for the following setup:
- Set up all 20 disks in a RAID-DP aggregate with one spare (17 data, 2 parity and one spare, or maybe two spares). - Bond a NIC from the first controller with a NIC from the second controller to give us a 2Gbps connection to our "storage network". - Third and fourth NIC's would go to our regular network.
My hope was that I could lose one filer head and the other would take over seamlessly. We'd lose half of our network bandwidth but still be up and running.
However, it sounds like my understanding of how the clustering works might have been a bit flawed and that I actually need to treat the filer heads as two separate filers. So I may be forced to do something like the following:
- Split my disks up between the two filers (7 data, 2 parity, one spare -- or maybe I can have one spare available to both heads). - Probably can't team NIC's from multiple filer heads meaning if I team the two NIC's on the filer I can no longer connect to my management network. I probably need to order more NIC's :( - If I lose one head, I lose one aggregate unless manual intervention is taken. - Each filer has a different hostname/IP for network access.
This maybe gives me better performance, but at the expense of total disk space and flexibility if my understanding is correct.
Maybe someone could help clear this up. It doesn't appear IBM has a RedBook on clustering... I'm searching around in NOW and have come across the Data ONTAP 7.3 Active/Active Configuration Guide which I am now reading.
Is there something similar for Active/Passive setups (which seems to be more what I am after) or other documents that would be recommended reading? Any advice or best practices?
This filer will be serving NFS to a pair of ESX servers. We plan to add a second shelf of disks later this year.
Thanks in advance. No sales inquiries please.
Ray