More and more Enterprises come to a decision to deploy Cisco Nexus switches in their corporate data centers. One of the main design considerations relates to Cisco 2200 Fabric Extenders (FEX) connectivity topology. To provide high availability Cisco Nexus 5500 series switches support different options to connect FEXes (all are based on a Virtual Port Channel feature):
- Straight-Through, where every FEX is connected to a single N5K (Active/Active and Active/Passive servers);
- Dual-Homed, where each FEX has one or more uplinks to two N5K switches (Active/Passive servers);
- Enhanced vPC, same as Dual-Homed but with Active/Active servers;
Each option has its own limitations and field of use, but this time we will concentrate our attention on the Dual-Homed FEX topology with Active/Standby Dual-Homed servers. Mainly because I recently deployed a pair of Cisco Nexus 5596UP switches with a number of Cisco 2248 TP-E Fabric Extenders using this approach.