35Identifying physical IRF ports on the member switchesIdentify the physical IRF ports on the member switches according to your topology and connectionscheme.Table 7 shows the physical ports that can be used for IRF connection and the port use restrictions.Table 7 Physical IRF port requirementsChassis Candidate physical IRF ports RequirementsS5150X-16S-EI 16 fixed SFP+ ports on the front panelAll physical ports to be bound to an IRFport must be the same type.S5150X-16ST-EI4 fixed SFP+ ports and 12 fixed1/10GBASE-T autosensing Ethernetports on the front panelS5150-24S-PWR-EI 4 fixed SFP+ ports on the front panelPlanning the cabling schemeUse twisted pair cables, SFP+ network cables, or SFP+ transceiver modules and fibers to connectthe IRF member switches. If the IRF member switches are far away from one another, choose SFP+transceiver modules with optical fibers. If the IRF member switches are all in one equipment room,choose twisted pair cables or SFP+ network cables. For more information about SFP+ networkcables and SFP+ transceiver modules, see "Appendix C Ports and LEDs."The following subsections describe several recommended IRF connection schemes, and all theseschemes use a ring topology.Connecting the IRF member switches in one rackUse SFP+ network cables to connect the IRF member switches (9 switches in this example) in a rackas shown in Figure 47. The switches in the ring topology (see Figure 48) are in the same order asconnected in the rack.