packet capture on Cisco ACI Leaf switches

Step1 – Identify the source & destination IP for which capture need to be performed

Step2 – Identify the leaf switches where the source & destination are connected (Use EP Tracker to identify the leaf switches)

Step3 – login to leaf switch on SSH where source is connected & set below packet capture

Leaf01#vsh_lc

module-1# debug platform internal tah elam asic 0
module-1(DBG-elam)# trigger reset
module-1(DBG-elam)# trigger init in-select 6 out-select 1
module-1(DBG-elam-insel6)# set outer ipv4 src_ip 1.1.1.1 dst_ip 2.2.2.2
module-1(DBG-elam-insel6)# set outer l4 dst-port 1533 (This step is optional in case specific port need to be captured)
module-1(DBG-elam-insel6)# start

Step4 – Once the packet capture is set, you need to confirm if packet are received on source server connected leaf

module-1(DBG-elam-insel6)# stat
ELAM STATUS
===========
Asic 0 Slice 0 Status Armed        (Armed keyword states no packet received yet)
Asic 0 Slice 1 Status Triggered   (This Triggered keyword shows the packet received)

Step5 – Once packet confirmed received on source leaf, repeat the same step on target leaf

Once confirmed that packets sent from source server & received on destination server, it’s confirmed that no packet getting dropped on the path

I hope this helps in your troubleshooting journey !!