Which interface / route is used in a port-channel / ECMP?

[Kevin-H]

Just like CEF w/ ECMP, we used to be able to see which port is used in a port-channel, when we supply a specific source-destination IP pair.

//3750
pghcenturylink2#test etherchannel load-balance interface port-channel 1 ip 1.1.1.1 2.2.2.2
Would select Gi1/0/47 of Po1
=========

Somehow on Cisco’s latest & greatest 3650 this is no longer available!?
Thought maybe they made this a hidden command, so pasted in the same command I used on the 3750, same thing.

pgh-hub-3650-01#test ether?
% Unrecognized command

pgh-hub-3650-01#$d-balance interface port-channel 1 ip 1.1.1.1 2.2.2.2
test etherchannel load-balance interface port-channel 1 ip 1.1.1.1 2.2.2.2
      ^
% Invalid input detected at '^' marker.

pgh-hub-3650-01#test port-ch?
% Unrecognized command

==========================

On a related subject, does anyone know how to see which port/path is used on Nexus, when there’s multiple ECMP routes?
On IOS, there’s the “sh ip cef exact-route“ command.
What’s the equivalent on NXOS?

TIA

[Georg Pauwen · Accepted solution]

Hello,

I think on the 3650 you can use the command 'show platform etherchannel' for testing:

https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst3650/software/release/3e/layer2/command_reference/b_Layer2_3_3e_3650_cr/b_Layer2_3_3e_3850_cr_chapter_010.html#wp2374758565

[paul driver]

Hello

---

@Kevin-H wrote:

On a related subject, does anyone know how to see which port/path is used on Nexus, when there’s multiple ECMP routes?
On IOS, there’s the “sh ip cef exact-route“ command.
What’s the equivalent on NXOS?

TIA

---

Try - 
show routing hash xxxxx xxxxx
or
show forwarding ???

res
Paul

[Kevin-H]

Thanks for the reply but show routing hash still gives me all available ECMP routes as possible paths.

Looking for a way to identify which path/interface is used, if there's a problem w/ a particular (src,dst) flow.

pghcore2# show routing hash 192.168.x.x 172.29.y.y
Load-share parameters used for software forwarding:
load-share mode: address source-destination port source-destination
Universal-id seed: 0x70ab866f
Hash for VRF "default"
Hash Type is 1
Hashing to path *172.29.y.y
For route:
172.29.y.y/31, ubest/mbest: 3/0
    *via 172.29.255.26, Eth1/34, [110/160], 4w1d, ospf-1, inter
    *via 172.29.255.59, Vlan501, [110/160], 4w1d, ospf-1, inter
    *via 172.29.255.60, Vlan501, [110/160], 4w1d, ospf-1, inter