We recently ordered WS-X6816-GBIC modules for our new 6513s, however we have been advised that they have reached EOL and that we can maintain our existing topology by purchasing 6516s instead. Apparantly we can still purchase the same DFCs (WS-F6K-DFC3BXL).
Q1 - In general terms, will the 6516 perform to the same specs to our 6816s?
Q2 - Also more specifically, with respect to throughput when installed into the dual fabric connected slots (9-13), does the 6516 make same use of the 256Gbps backplane as the 6816?
This is a bit of a minefield at the moment :-)
The 6816 has 2 8 Gbps connections to the switch fabric and is dCEF enabled.
The 6516A has only 1 8Gbps connections to the switch fabric and needs an upgrade for dCEF.
Both cards make use of the 256Gbps switch fabric as they are both fabric enabled.
See attached link -
The added complication is that DFC cards are EoS March 2008. So even though the 6516A is not EoS cisco are recommending any new installations or potential upgrades to 6516A to replaced with the WS-X6724-SFP.
The WS-X6724-SFP has a single 20Gbps connection to the switch fabric. The catch is that you need to be running a Supervisor 720 to use this blade and obviously the connectors are different - GBIC vs SFP.
So to summarise :-)
If you don't have Sup720 or absolutely must have GBIC connectors go with 6516A and upgrade to dcef but do it before end of March !! and be aware that you will only get 1 8Gbps channel to switch fabric ie. 2:1 oversubscription. This may or may not be a problem.
If you do have a Sup720 consider the WS-X6724-SFP (1 x 20Gbps connection) or the WS-X6748-SFP (2 x 20Gps connections). This is Cisco's recommended path.