5 Replies Latest reply on Nov 6, 2012 11:31 AM by john_s@intel

    RT3WB080 with RES2SV240 Port Expander

    Greg Huggins

      I added the RES2SV240 expander to my RT3WB080 so that I could add more hard drives to my backup server.  Before I added the RES2SV240 I used both SFF8087 connectors on the RT3WB080 for 0-3 and 4-7 that attached to the hard drives and the drives showed up as being connected to 0-3 and 4-7 via the SFF8087 cable to the 4 SATA drives for each SFF8087.

       

      I am confused that when I added the RES2SV240 and connect both SFF8087 cables from the RT3WB080 to the RES2SV240 all of the drives show up as on ports 0-3. I disconnected the cable from the RES2SV240 connected to the RT3WB080 that went to ports 4-7 and all of the drives still showed up as attached to 0-3 and the arrays were still properly as before.

       

      I could not find in the instructions for the RES2SV240 whether to connect both SFF8087 cables from the RT3WB080 but the instructions only showed one cable from the RT3WB080 to the RES2SV240 with 10 hard drives attached if I remember correctly. 

       

      I guess that my questions are:

       

      1)  Is the other SFF8087 every used from the RT3WB080 to the RES2SV240 and if so for what?

      2)  Can the extra SFF8087 from the RT3WB080 be connected to 4 other drives not connected to the RES2SV240 or must all of the additional drives be connected to the RES2SV240?

       

      Thanks in advance,

       

      Greg H.

        • 1. Re: RT3WB080 with RES2SV240 Port Expander
          john_s@intel

          Greg,

           

          See the RES2SV240 support page. There you can find the Intel® RAID Expander Card RES2SV240 hardware user guide.

           

          Regards,

          John

          • 2. Re: RT3WB080 with RES2SV240 Port Expander
            Greg Huggins

            This does not answer the questions that I inquired about.  I had already read this document and referenced it in my initial message.  It talks about 4 in 20 out or 8 in and 16 out but no explanation on what this is actual used for or means.

             

            Greg H.

            • 3. Re: RT3WB080 with RES2SV240 Port Expander
              john_s@intel

              Greg,

               

              The RT3WB080 has two SFF-8087 ports that consist of four SATA ports each. The RES2SV240 has 24 "ports" through six SFF-8087 connectors. The ports of the RES2SV240 are like network switches, with some limitations. You can connect one of the SFF-8087 ports from the RT3WB080 to the RES2SV240 and use the remaining 20 (five SFF-8087 ports) to connect to disk drives. Or you can connect the two SFF-8087 ports from the RT3WB080 to the RES2SV240 and use the remaining 16 (four SFF-8087 ports) to connect to disk drives.

               

              The RT3WB080 individual ports then become waterfall type of connections. If you're pushing less than 6Gb (theoretical) from the RT3WB080 to the RES2SV240, you'll only use a single port. If you go over 6Gb, it'll fall over to additional ports to take up the slack. So in reality, using the two SFF-8087 ports from the RT3WB080 to the RES2SV240 is kind of overkill.

               

              If you connect only one connection from RT3WB080 to the RES2SV240 you can use the other one to connect to to other HDDs, another backplane or expander. It gets more complicated when you do this kind of thing through. You shouldn't mix disks from separate expanders and backplanes in single arrays.

               

              John

              • 4. Re: RT3WB080 with RES2SV240 Port Expander
                Greg Huggins

                John,

                 

                Thanks for the detailed answer.  That is exactly what I was looking for and kind of what I though would happen.  It would be nice if this information was brought out in the hardware documentation for the expander card. The documentation only shows one SFF8087 connected to the expander card so you are kind of left handing on what to do with the other SFF8087.  It may be in the hardware documentation for the RT3WB080 and I will check. 

                 

                Thanks,

                 

                Greg H.

                • 5. Re: RT3WB080 with RES2SV240 Port Expander
                  john_s@intel

                  Appreciate the feedback Greg.  The communities are a good place to get this kind of information, or an indication of a lack of information.

                   

                  I'll look around too and if I don't find anything, I'll create a web article with it.

                   

                  John