The uplinks on the Supervisor Engine 6-E have three options in redundant mode operation:-
1 + 1 redundancy In this configuration, only one 10 Gigabit Ethernet uplink port on each of the two supervisor engines carries traffic, and
each port forwards traffic at line rate.
2 + 2 redundancy In this configuration, both 10 Gigabit Ethernet uplink ports on each of the two supervisor engines are forwarding traffic
and the uplinks are 2:1 oversubscribed.
4 + 4 redundancy. In this configuration, twin gigabit converter modules are used and all four Gigabit Ethernet uplink ports on each of the two
supervisor engines carry traffic simultaneously at wire rate.
Prior to Cisco IOS Release 12.2(44)SG the Supervisor Engine 6-E allowed either dual wire speed 10GbE ports or four Twin-Gigabit converter based GbE SFP uplink ports when operating in redundancy mode
Cisco IOS 12.2(46)SG includes a Shared-Backplane Mode* which enables all front-panel ports on both Active and Standby Supervisor Engines. The capability is supported on all Catalyst 4500 and 4500-ESeries Chassis with the Supervisor 6-E. This configures a 2:1 Oversubscription.
By – Alok CCIE -DC #42872
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