Two-Rack Cabling for a System Combining an X8M Rack and a Later Model Rack

This section provides the cabling details to connect an X8M rack with an RA21 or later model rack, both of which use RoCE Network Fabric.

Note:

  • The following conventions are used in the cabling notation for connecting multiple racks together:

    • The abbreviation for the first (X8M) rack is R1, and the second (RA21) rack is R2.

    • LL identifies a lower leaf switch and UL identifies an upper leaf switch.

    • SS identifies the spine switch, which is located in U1 on all racks.

    • A specific switch is identified by combining abbreviations. For example, R1LL identifies the lower leaf switch (LL) on the first rack (R1).

  • The leaf switches are located as follows:

    • At rack unit 20 (U20) and 22 (U22) in 2-socket systems (Recovery Appliance X8M-2 or X9M-2, or Storage Expansion Rack X8M-2 or X9M-2).

    • At rack unit 21 (U21) and rack unit 23 (U23) in 8-socket systems (Recovery Appliance X8M-8 or X9M-8).

  • The cable lengths shown in the following lists assume that the racks are adjacent to each other, the cables are routed through a raised floor, and there are no obstacles in the routing between the racks. If the racks are not adjacent, or use overhead cabling trays, then they may require longer cable lengths. Cable lengths up to 100 meters are supported.

  • Only optical cables (with additional transceivers) are supported for lengths greater than 5 meters.

The following illustration shows the cable connections for the spine switches when cabling a two-rack hybrid system with an X8M rack and an RA21 or later model rack:

The following tables contain details for all of the RoCE Network Fabric cabling connections in a two-rack hybrid system with an X8M rack and a later model rack.

Table 19-1 Leaf Switch Connections for the X8M Rack (R1)

Leaf Switch Connection Cable Length

R1UL to R1SS

R1UL-P5 to R1SS-P5

R1UL-P7 to R1SS-P7

R1UL-P4 to R1SS-P9

R1UL-P6 to R1SS-P11

3 meters

R1UL to R2SS

R1UL-P31 to R2SS-P5

R1UL-P33 to R2SS-P7

R1UL-P30 to R2SS-P9

R1UL-P32 to R2SS-P11

5 meters

R1LL to R1SS

R1LL-P5 to R1SS-P13

R1LL-P7 to R1SS-P15

R1LL-P4 to R1SS-P17

R1LL-P6 to R1SS-P19

3 meters

R1LL to R2SS

R1LL-P31 to R2SS-P13

R1LL-P33 to R2SS-P15

R1LL-P30 to R2SS-P17

R1LL-P32 to R2SS-P19

5 meters

Table 19-2 Leaf Switch Connections for the RA21 or Later Model Rack (R2)

Switch Pair Connections Cable Length

R2UL to R1SS

R2UL-P1 to R1SS-P6

R2UL-P2 to R1SS-P8

R2UL-P3 to R1SS-P10

R2UL-P4 to R1SS-P12

R2UL-P5 to R1SS-P14

R2UL-P6 to R1SS-P16

R2UL-P7 to R1SS-P18

5 meters

R2UL to R2SS

R2UL-P30 to R2SS-P6

R2UL-P31 to R2SS-P8

R2UL-P32 to R2SS-P10

R2UL-P33 to R2SS-P12

R2UL-P34 to R2SS-P14

R2UL-P35 to R2SS-P16

R2UL-P36 to R2SS-P18

3 meters

R2LL to R1SS

R2LL-P1 to R1SS-P20

R2LL-P2 to R1SS-P22

R2LL-P3 to R1SS-P24

R2LL-P4 to R1SS-P26

R2LL-P5 to R1SS-P28

R2LL-P6 to R1SS-P30

R2LL-P7 to R1SS-P32

5 meters

R2LL to R2SS

R2LL-P30 to R2SS-P20

R2LL-P31 to R2SS-P22

R2LL-P32 to R2SS-P24

R2LL-P33 to R2SS-P26

R2LL-P34 to R2SS-P28

R2LL-P35 to R2SS-P30

R2LL-P36 to R2SS-P32

3 meters