Hi Folks, just thought I'd share with you some b/w config for MDS9222i port-groups.
We know we have 12.8Gbps of b/w available per port-group, and we are also told that when we use all 12Gbps for dedicated mode, then the remainign 0.8Gbps is split between the remaining ports in the port-group. Great. So then we should be able to do the following:
fc1/1 = shared 4.0Gbps
fc1/2 = shared 4.0Gbps
fc1/3 = dedicated 4.0Gbps
fc1/4 = dedicated 4.0Gbps
fc1/5 = dedicated 2.0Gbps
fc1/6 = dedicated 2.0Gbps
However, when you try to do this, you get an error: (error) Bandwidth not available
Eh! What!
Well, it turns out, that ports in shared mode, by default get 1Gbps of b/w, so when trying to do the above, what we are actually doing is: 1+1+4+4+2+2 = 14 and as we know 14 > 12.8 !
So, to get around this we need the 'no rate-mode oversubscription-limit module x' command.
This means our shared ports, now no longer consume 1Gbps, but instead consume 0.27Gbps, so we now have: 0.27+0.27+4+4+2+2 = 12.54Gbps and 12.54 < 12.8, so we are good to go:
MDS9222i(config-if)# int fc1/1-2
MDS9222i(config-if)# no out-of-service
fc1/1: (error) Bandwidth not available
fc1/2: (error) Bandwidth not available
MDS9222i(config-if)# no rate-mode oversubscription-limit module 1
MDS9222i(config)# int fc1/1-2
MDS9222i(config-if)# no out-of-service
MDS9222i(config-if)#
MDS9222i# sh port-resources module 1
Module 1
Available dedicated buffers are 3991
Port-Group 1
Total bandwidth is 12.8 Gbps
Total shared bandwidth is 0.8 Gbps
Allocated dedicated bandwidth is 12.0 Gbps
--------------------------------------------------------------------
Interfaces in the Port-Group B2B Credit Bandwidth Rate Mode
Buffers (Gbps)
--------------------------------------------------------------------
fc1/1 16 4.0 shared
fc1/2 16 4.0 shared
fc1/3 16 4.0 dedicated
fc1/4 16 4.0 dedicated
fc1/5 16 2.0 dedicated
fc1/6 16 2.0 dedicated