ASICs

- "show asic-version slot x" will show the count of ASICs like Rohini (Port ASIC), Janus (Fabric interface)

Took it from here.
There is no oversubscription built in to the Rohini-Janus interconnect. The oversubscription on these cards is from janus to the fabric. Also intra Janus there is a 26Mpps limitation.

To elaborate, 6748-GETX is as you say, 1-12, 13-24, etc. The port mapping for the fiber version of 6748, and for 6724, is a bit different, it is even & odd (so eg, 1-23 odd, 2-24 even, etc) but yes it is 12 ports per rohini in all cases.

WRT oversubscription, again, the oversub is at the fabric level, not the port level as you would see on some 4500 series cards & on the 6500 series 6148-GETX etc.

Notes on 6708

- There are 2 flavors - 3C and 3CXL.
- 6704 has 16MB per port buffer, 6708 has 200MB per port buffer
- 8 x 10G ports with 40Gbps (2 x 20Gbps) to Fabric (2:1 fabric oversubscription ?)
- 64Gbps local switching (1.25:1 local oversubscription ?)
- 48Mpps switching
- "no hw-module slot x oversubscription" will turn off oversubscription, effectively shutting down port 3,4,7 and 8.
- in non-oversubscribed mode, port 3,4,7 and 8 cannot be unshut and "show interface" output will be "disabled for performance" instead of normal admin disable
- "mac-address-table synchronize" is enabled by default (and fix PFC/DFC MAC synchronization problem )