Ecmp Forwarding Failure; Symptom - H3C S6805 Series Troubleshooting Manual

a. Execute the display bgp peer l2vpn evpn command on the devices to view their BGP
settings.
b. Verify that the EBGP or IBGP peers on the devices have matching AS numbers. If the AS
numbers do not match, use the peer as-number command to modify the AS numbers.
c. Verify that the devices use different router IDs. If the devices use the same router ID, use
the router-id command to modify the router ID of one device.
2. Verify that the devices have connectivity:
a. Verify that one device can ping the other device.
b. If the ping fails, check for link failure and verify that the devices have routes to each other.
3. Verify that the memory usage of each device is below the critical alarm threshold:
a. Execute the display memory-threshold command on each device to view its memory
usage.
b. Verify that the memory usage is below the critical alarm threshold in the last 10 minutes.
c. If the memory usage stays above the critical alarm threshold, contact Hewlett Packard
Enterprise Support.
4. Perform the following tasks to collect information and contact Hewlett Packard Enterprise
Support:
a. Execute the debugging bgp event command to view possible causes for neighbor
relationship setup failure, such as connection setup errors and connection conflicts.
b. Execute the debugging bgp open command to view errors in OPEN message
transmission and receipt.
c. Execute the debugging tcp packet command to view TCP packet exchange failure.
d. Execute the display bgp peer l2vpn evpn verbose command to view neighbor address
family negotiation information and packet transmission and receipt history.
e. Execute the display bgp peer l2vpn evpn log-info command to view neighbor status
changes and neighbor down reasons.
f. Execute the display system internal bgp peer l2vpn evpn session statistics command
to view session status details.

ECMP forwarding failure

Symptom

In an EVPN network, the device cannot forward packets through ECMP routes.
38