I’m interested in picking up some SSDs for the SAS bays in my R720s but can’t seem to find anything comparable in price to m.2/pcie. Typically in talking about farm setups people post “2x 2tb ssds” or the like without specifying the model, I would love to get some input on specific models that might be cost effective.
Are you talking about actual sas interface ssds or do you want to just put ssds in the slots.
I would image most people are using still using sata 6gb/s ssds due to the insane price points of sas models. I don’t have any sas models. But I’m using western digital and Samsung sata 6gb drives in my sas arrays that are working very well.
I didn’t realize you could do that! Do you need an adapter to put the SATA drives in the SAS bays? I definitely feel like there’s something super basic I’m missing.
you can put a sata drive in a sas slot, but you can’t put a sas drive in a sata slot.
Don’t feel bad it took me like a week to figure that out. It seems to be a “expected known” among most people using servers so theres little documentation for us newbs to figure it out
Just make sure when you get your drives they are raw. There’s a guide around here somewhere, put em in trays and send it
@parkers brings excellent information here.
One of the big differences between SATA and SAS is the transfer speed. Using SATA disks with SAS cables, you will be limited by the SATA transfer speed.
- Sata I : 150 MB/s
- Sata II : 300 MB/s
- Sata III : 600 MB/s
- SAS : 600-1500 MB/s
You will most probably need to re-flash the raid card if you use the front panel disks (onboard storage).
Here’s some info on re-flashing raid, etc.:
Is there a way to bypass RAID in order for Zero-OS to have bare metals on the system? (No RAID controller in between storage and the Grid)
Yes it is possible. “You can use the onboard storage on a server without RAID. You can re-flash the RAID card, turn on HBA/non-RAID mode, or install a different card. No need for RAID.” @FLnelson It’s usually easy to set servers such as a HP Proliant with the HBA mode. For Dell servers, you can either cross-flash the RAID controller with an “IT-mode-Firmware” (see this video) or get a DELL H310-controller (which has the non-RAID option). Otherwise, you can install a NVME SSD with a PCIe adaptor, and turn off the RAID controller.
Hope it helps! Happy farming!
just to add, I was able to continue using raid even with my ssds by keeping all logical drives under 1.1 tb. i had detection issues with arrays over 1.1 on my hp raid card.
Very interesting. What was your raid configuration apart from having the logical drives under 1.1TB? Did you do RAID 0 or else?
I went with raid zero,
I remember from something I was doing in fdisk is that one a drive is over a certain size it changes a table type, I remembered seeing the 1.1tb table marked as legacy somewhere so I tried that and it worked lol. Honestly I’ve been so buried in my terminal lately I don’t remember the name of that table
OK thanks for sharing those info, that’s nice to know. It opens up some more possibilities for TF farmers knowing you don’t need to re-flash in certain situations.
One last thought, I also deleted all logical drives and created completely new arrays with raw disks. I wonder if it’s possible that an established array that booted something else at some point has some data left even if you wipe the logical array, possibly stored in the raid controller that zos picks up.
I’d test the theory but I just did an offline for upgrades a couple days ago. I wonder if op could attempt to leave his raid card flashed normally, delete all logical Partitions , establish one raid zero with all ssd(s) and one raid zero all hdd(s), this could have some potential, the read/write speed of a full sas array could likely outrun most ssds and open a huge Avenue for low cost hardware if those could be run in place of ssds?