ExtremeXOS 31.5 supports SFP-DD cabling on ExtremeSwitching 5420 series switches. The two stacking/SFP-DD ports are “Universal Ethernet” ports, labeled “U1” and “U2.” These ports can operate either as stacking ports or Ethernet ports.
When used as Ethernet ports, the U1 and U2 ports can support data rates of either 10Gb using SFP+ optics or 20Gb using SFP-DD optics. 5420M switch models support two 10Gb channels on each SFP-DD port when the ports are used as Ethernet ports. 5420F switch models support one 10Gb channel on each SFP-DD port when the ports are used as Ethernet ports. Use the disable stacking-support command to set the U1 and U2 ports in Ethernet mode.