Need some info on my server build.

[PharetH]

Main File Server - Two Norco cases built into one.
Amount of storage in the following system: 32.7TB
Case: NORCO RPC-4220 (Top Case), NORCO RPC-4224 (Bottom Case)
PSU: Corsair 950w (Top Case), Corsair 850w (Bottom Case)
CPU: Intel Quad Core Xeon X3330
Motherboard: Asus P5BV-M
RAM: 8GB (4x2GB)
Hard Drive: Western Digital 64GB SSD
Hard Drive: 21x Hitachi 7K2000 HDS722020ALA330 (Raid 6 + Hotspare)
Raid Card: Areca ARC-1680IX-24-2G w/BBU + HP SAS Expander
Operating System: Server 2008 R2 x64

I have a couple questions about my recent build, I'm hoping you guys can shed some light on a couple of things. If you look at the picture, I have the top case full of Hitachi 2TB drives in a Raid 6 (20 Total) connect via 5 sas cables to the 1680IX, and the bottom case connected to the HP SAS expander via 1 sas cable to the last internal port on the 1680IX. If I start migrating new drives connected to the sas expander into the current raidset, will I start seeing drive timeouts and performance loss? I really would rather not create a new raidset for the bottom case if I dont have to. Next question, If I were get another case and HP expander and connect it to the external port of the 1680IX, would that cause any problems with the other expander. I thought I read somewhere on these forums that the 1680IX does not like working with more then 1 HP expander.

Please let me know if you have any answers/suggestions.

 

[PigLover]

The 1680ix has an internal SAS expander built in in order to reach 24 ports (6 mini-SAS connectors). By using another expander, you are essentially daisy-chaining SAS expanders. While this should work OK in theory, many people have reported problems when using this card with both HP and other SAS expanders. I think you can safely say it will not work, or if you can make it work it will always be a source of worry - and I presume the whole reason you are investing in expensive raid solutions is because you don't desire to worry.

The external port on the 1880ix is apparently not connected through the internal expander, I don't know if this applies to the 1680ix, but you might want to try your proposed configuration using the external port. It could work. Always worth the test...beats trusting others. Just promise to report back so that others can learn too!

The HP SAS expander appears to work well with the Areca SAS cards that do not have the internal expander. You may want to trade in for an 1680i (not ix) or 1880i (not ix). These are both 8-port cards (two mini-SAS connectors). Get an additional HP SAS expander, with each chassis being connected via of the mini-SAS connectors to an expander to serve up to 24 drives each.

 

[PharetH]

Thanks for the reply PigLover. My HP card seems to be working fine on the internal ports, no hangups or issues with it detecting drives like others have reported. Maybe i'm just lucky?

Does that mean i'm good to go?

 

[PigLover]

I think I'd want to try more than one drive configured as a hot-standby before being satisfied. Load it up with a few more, build a separate raidset on it, and then load-test it some. If it stays stable then be happy, tear down the test and add drives to your existing raidsets all you want.

 

[MrGuvernment]

raid 6 and 1 hot spare?

is it one giant raid 6 array?

for how long 2T drives take to rebuild i would feel safer doing multiple smaller raid arrays instead of one giant raid 6.

 

[PharetH]

Right now its a 20 drive Raid6 with the one hotspare just to test the expander I added. I'm going to try stress testing it with a 7x 1TB drives I have laying around to see if it stays stable. I would prefer to stick with one giant raid6 because it's easier, but with the way 3TB drives are coming down in price, I may start a whole new raidset in the bottom case using the 3TB Hitachi drives newegg has for $130.

Thanks for the suggestion PigLover. Hopefully theres a couple more people that could add some other suggestions.

 

[odditory]

I have several instances of that exact case configuration - RPC-4224 on bottom and RPC-4220 on top for 44 total ports. My advice is don't span arrays across multiple cases. If you want to grow your 20-drive array then put it in the 24-bay case- you don't want to grow a RAID6 volume larger than 24 drives anyway, when 20 is already pushing it. I would also skip Hitachi 3TB drives if you care about cost/GB. The sweet spot right now is Hitachi 5K3000 2TB's at Fry's for $70 - thats all I buy now for additional space.

Your SAS topology isn't ideal, in terms of the way you're connecting expanders to your 1680IX. Ideally you should be connecting the external SFF-8088 port of the HP expander to the external SFF-8088 port of the Areca card, but I can't remember if that works - if I recall when I had a 1680IX-24, it was either use the external connector and sacrifice the internal ports, or vice versa so you might have to play with the SAS Mux setting.

Just for reference, my systems have the motherboard in the RPC-4224, Areca 1880i connected to an HP expander internally, and then an SFF-8087 to SFF-8088 PCI adapter connecting the Areca's other SFF-8087 port to the expander in the RPC-4220.

 

[Zerosum]

I have several instances of that exact case configuration - RPC-4224 on bottom and RPC-4220 on top for 44 total ports. My advice is don't span arrays across multiple cases. If you want to grow your 20-drive array then put it in the 24-bay case- you don't want to grow a RAID6 volume larger than 24 drives anyway, when 20 is already pushing it. I would also skip Hitachi 3TB drives if you care about cost/GB. The sweet spot right now is Hitachi 5K3000 2TB's at Fry's for $70 - thats all I buy now for additional space.

How would you break up the 24 drives in each bay? 2 10-drive Z2 and a 4 drive ?? I need to reorder my systems alittle cleaner Thought with 4k sectors, that was the recommended config?

I have 2 more of the 4224 ready to be set up. I was going to just go with 5 8 drives-z2. But that would split one array between the 2 cases which thinking about it would be better if I can avoid.