4.1
Benefits of VLT
In a non-Virtual Link Trunking (VLT) environment utilizing spanning tree protocol, as in Figure 8,
redundancy involves idle equipment and increased costs with no added value in the event of a device
failure. On the other hand, in a VLT environment (Figure 9), all paths are active, utilizing all available
links and switches to their fullest potential. This doubles the throughput, thus increasing performance
and adding immediate value.
Non-VLT
Environment
Non-VLT Environment with Active/Passive (Standby)
VLT
Environment
VLT also takes advantage of teamed Network Interface Cards (NICs) and switch pairs, causing them
to appear as a single switch to devices outside the VLT domain. The physical versus logical
connectivity, using a pair of FN IOMs in a PowerEdge FX2 chassis, is illustrated below in Figure 10
and Figure 11.
PowerEdge FX2 – FN I/O Module – VLT Deployment Guide | Version 2.2
13
Active Path
VLT Active-Active Environment
Idle
Active Path