r720 can i connect sas/sata hdd without a controller card?

Question

I have an r720 with no raid card. When I plug an ssd or 15k/10k sas drive into the hotswap backplane, the chassis recognizes that the drive is plugged in (I get an orange light and lcd alert that the drive is removed when I take it out). However, the bios and OS don't seem to recognize any of the hotswap drives (they only see the optical drive attached to the sata ports on the motherboard.

Do I need a controller card to use drives plugged into the backplane, or is there a way to use the backplane without a controller card? I do not need raid functionality.

Thanks in advance.

-shane

Daniel My · Accepted Answer

Hello Shane

Do I need a controller card to use drives plugged into the backplane, or is there a way to use the backplane without a controller card? I do not need raid functionality.

Yes, you have to have a controller connected to the backplane. If you purchased the system without a RAID controller then there should be a SAS cable that goes from the backplane to the S110 chipset controller slot on the system board.

You can use the onboard S110 SATA controller for communication with the backplane. There are many limitations to the S110 controller, so it may not suit your needs. You will likely need to purchase the LSI 9207 if you want the drives to perform in a non-RAID environment. The other options are a PERC H710; which you could set the drives in single drive RAID 0s. In that state they operate like non-RAID drives. You could also get an H310. The H310 supports non-RAID mode, but we added some functionality to the H310 that are not present in previous versions of the card. In doing so it has reduced performance when operating in non-RAID mode.

The reason I say you will likely want a different controller than the S110 is because you mentioned you have SAS drives. The S110 is a SATA only controller. Also, the S110 only supports up to 4 drives.

To access the RAID BIOS make sure the S110 is enabled in the system BIOS. In the BIOS go to SATA settings. In the drop down set the mode to RAID. This will turn on the S110 controller. Then you can configure the drives in the S110 BIOS during boot with CTL R. I'm not sure what operating system you are installing, but the S110 is only compatible with Windows.

Thanks

Daniel My · Accepted Answer

I was unable to get the SSD to show up even when enabling raid mode on the s110 (It didn't show up in the CTRL-R configuration screen).

It should show up in CTL R no matter what operating system you are running. The problem you will run into with unsupported operating systems is that there is not a compatible driver.

Make sure the drives are plugged into slots 0-3, and check to make sure there is a SAS cable that goes from the backplane to the system board. If you look at the diagram on the underside of the chassis cover it is labeled as E - SW RAID. The SAS cable should go from the backplane to that connector(E).

If it is cabled properly and still not detecting the drives then there may be a compatibility issue. I would try to find some other SATA drives to test functionality with.

Thanks

ntshane · Answer

Thanks so much, this is very helpful information. Yes, my end goal is to use sata SSD with the backplane, I plugged in the SAS drives only for the purposes of testing. It is sounding like I will need to purchase a controller card. I was unable to get the SSD to show up even when enabling raid mode on the s110 (It didn't show up in the CTRL-R configuration screen). I understand that the S110 is only compatible with Windows, but I was wondering if this is only with respect to raid. That is, will the drives show up, but not be in a raid mode? Or will they just not show up at all? I have seen other systems with software raid that, although they didn't allow raid operation in non-windows, the drives would still be accessible as individuals. I hope that makes sense. Thanks again, -shane

ntshane · Answer

Excellent, thanks again!

Daniel My · Answer

So, the cable is not plugged into 'E-SW RAID' but into a port near it labeled 'Internal SAS'

Yes, Internal_SAS is C on the diagram. That is the connector the integrated RAID controller daughter card. There is an integrated RAID storage slot designed specifically for a PERC. The cable for the daughter card connects to the system board and is routed through the board to the PERC.

Technology wise the two cables should be identical; however the SAS cable is too short to reach the SW_RAID connector, and I'm pretty sure it is a double connector whereas the SW_RAID is a single connector. You are correct in your assertion that it will not work in the SW_RAID slot.

Thanks

ntshane · Answer

So, the cable is not plugged into 'E-SW RAID' but into a port near it labeled 'Internal SAS'. The cable appears to be incompatible with 'E-SW RAID'. I think I'm just going to have to purchase a proper controller card.

xerox445 · Answer

Dell Daniel,

I found this post from a few years ago. I am trying to get 10k 900gig SAS drives to work in a similar setup to this users, that has the onboard s110. I have purchased a H310 controller to add on, and used the cable that was plugged into the port E, to the first port on the new raid card. The drives light up and can be seen by the card it seems, but when I go into my OS, (unraid free BSD) they arent there. If I take one out, and swap in a 500gig sata drive, oddly enough, the activity lights do not work, but the drive is recognized in my OS. I have 8 total, and have tried 6 different SAS drives, all the same thing. Is this cabling or backplane that came with the server also not sas compatible because it shipped with the s110?

umirza85 · Answer

Any luck sorting this out....I came upon this a few more years later and am in the same spot. Picked up an r720xd and also 8x 1tb SAS drives.

DELL-Joey C · Answer

Hi @umirza85   What issue have you ran into? Can you provide as much information as much, so the community can help you in.    Here's the backplane cabling guide: https://dell.to/3oAFDub

PowerEdge HDD/SCSI/RAID

r720 can i connect sas/sata hdd without a controller card?

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