Hi,

I have an AMD 9950X based "server" in a 4U Chassis, running the LSI 9305-24i HBA which, until earlier this week, has been running 24 HDD's without issue for a long time.

I also have 2 other machines simialr to this, but the processing power I was using them for is no longer required. In an effort to slightly reduce power consumption and sell of still valuable hardware, I wanted to go down to 1 server but retain all my storage - and allow room for futher expansion.

So I bought 3 x Netapp DS4246 Disk Shelves and associated cables and an Adaptec  AEC-82885T 2283400-R  SAS Expander, having never used such things before.

I've connected the 9305-24i to the  AEC-82885T with a single SAS cable, which then in turn runs back to the internal backplane of the main chassis keeping all those drives connected, and then externally to the DS4246's.

My problem is daisy-chaining.

Everything is working fine, as long as I only connect 1 of the D4246's. Each of them work fine independantly, all 48 disks are found (24 internal, 24 external), but as soon as I power on any of the other shelves the PC just hangs pre-boot. If I boot with just one of them on and then turn on the others, no problem as such, but they are not detected. 

Is the AEC-82885T not suitable for chaining 3x DS4246's behind one of it's single external ports (single path config - keeping things nice and simple)?

If so is there another similar card that you'd reccomend? I have no spare PCIe ports on my MoBo and my HBA has no external ports so whatever it is needs to allow for molex or sata power like this Adaptec does...

Thanks!

Did you try disabling the HBA BIOS in the controller or the board BIOS, if there's one it may help,and it's not needed for Unraid.

5 minutes ago, JorgeB said:

Did you try disabling the HBA BIOS in the controller or the board BIOS, if there's one it may help,and it's not needed for Unraid.

Hi. Thanks for trying to help. I've not done this now, honestly I wouldn't know how. When the PC boots there's no obvious BIOS being shown for the HBA - though I've seen online screenshots to suggest that I should see something. Perhaps that means it's already disabled?

Check the BIOS for the OPT ROM setting for the various PCI slots; it could also be global, and set that to disabled if enabled.

Just now, JorgeB said:

Check the BIOS for the OPT ROM setting for the various PCI slots; it could also be global, and set that to disabled if enabled.

Thanks - I'll take a look.

Double check to ports used to daisy chain, there is a specific way to daisy chain these units.

A quick google will show correct way.

22 minutes ago, tjb_altf4 said:

Double check to ports used to daisy chain, there is a specific way to daisy chain these units.

A quick google will show correct way.

Thanks! This much I'm confident on, I'm sure they are wired correctly.

24 minutes ago, tjb_altf4 said:

Just to add, I've daisy chained DS4246 directly off a 9305-16e, but not via an expander... it might be your issue.

If you don't need the internal connections, a 9305-8e or 16e would be ideal.

Otherwise the other option to try is a straight passthrough which would be better than going through an expander.
e.g. SFF-8643 to SFF-8644 Mini SAS Adapter

2 minutes ago, tjb_altf4 said:

Just to add, I've daisy chained DS4246 directly off a 9305-16e, but not via an expander... it might be your issue.

If you don't need the internal connections, a 9305-8e or 16e would be ideal.

Otherwise the other option to try is a straight passthrough which would be better than going through an expander.
e.g. SFF-8643 to SFF-8644 Mini SAS Adapter

Thanks... The expander is necessary as I use all the ports on my HBA internally already.

It's frustating as everything I read says that this should work just fine - even other people that appear to have done it almost exactly the same way. However it is true to say that I can do it differently by taking internal SAS connections that are availabel on the expander, using an adapter much like you have suggested, and effectively connecting each of the 3 DS4246 directly to the Server rather than chained together.

It's pretty cost neautral as I can return all of the external cabling - seems highly likely that it'll work seeing as I can get 1 of them to work this way... It's just really annoying as it shouldn't be necessary

Parts all finally arrived. Connecting shelves 2 & 3 directly to my SAS expander worked first time, so whatever problem I was having, it was specific to the daisy-chain setup of the 3 disk-shelves.