ARISTA - VXLAN Troubleshooting
Checking VXLAN Tunnel Status
To verify the status of VXLAN tunnels, use the following command:
show vxlan tunnel
This command shows information about the VXLAN tunnels including tunnel IDs, state, and the associated interfaces.
Checking VXLAN Interfaces
To view the VXLAN interface configuration:
show running-configuration interface Vxlan1
This command will display the configuration of a specific VXLAN interface, such as Vxlan1. You can check the VXLAN source interface, remote VTEP IP addresses, and other details.
VXLAN Forwarding Table
To check the VXLAN forwarding table, which maps VXLAN Network Identifiers (VNIs) to Layer 2 and Layer 3 addresses:
show vxlan forwarding
This will show all mappings of VNIs, the associated MAC addresses, and IP addresses.
Checking VTEP (VXLAN Tunnel Endpoints) Neighbors
To see the VTEP neighbor information, including the status and remote IPs of other VXLAN devices:
show vxlan neighbors
This command gives you the list of remote VTEP peers, their tunnel states, and additional statistics.
Checking MAC Address Table for VXLAN
To view the MAC address table for VXLAN:
show mac address-table vxlan
This command will display MAC address learning entries for VXLAN, allowing you to check if MAC addresses are being correctly learned or flooded.
Checking Routing Table for VXLAN
To check the IP routing table for VXLAN:
show ip route vxlan
This will show you the IP routes for VXLAN and their associated next hops.
Verifying VXLAN Configuration Consistency
To verify that your VXLAN configuration is consistent across the device:
show running-configuration | section vxlan
This command filters the running configuration to display only the VXLAN-related settings, making it easier to spot inconsistencies.
Checking Layer 2 Overlay Status
To check the status of the Layer 2 overlay and ensure that VXLAN segments are functioning:
show ethernet-switching table vxlan
This will show the Ethernet switching table for VXLAN and indicate whether there are any issues with the Layer 2 forwarding over the VXLAN network.
VXLAN BGP EVPN Status
To check the status of VXLAN BGP EVPN (Border Gateway Protocol Ethernet Virtual Private Network), including routes and neighbors:
show bgp l2vpn evpn
This will show BGP EVPN status, including the advertised routes and BGP neighbor information specific to VXLAN.
Checking VXLAN MTU (Maximum Transmission Unit)
To check the VXLAN MTU settings and ensure they are configured correctly for the encapsulation overhead:
show system mtu
This command helps to verify that the MTU is sufficient for VXLAN encapsulation and avoid issues like packet fragmentation.
Verifying the VXLAN Data Plane
To verify the VXLAN data plane and check for any dropped packets or other issues:
show interface Vxlan1 counters
This will show detailed statistics on the VXLAN interface, including the number of packets sent/received and any errors or drops.
Troubleshooting VXLAN Bridging
If you're facing issues with VXLAN bridging, you can check the bridging status:
show bridging vxlan
This will display the status of VXLAN bridging, which helps in troubleshooting Layer 2 bridging problems within a VXLAN overlay.
Debugging VXLAN Issues
For deeper troubleshooting, use the following command to enable debugging for VXLAN:
debug vxlan
This command provides detailed debug information for VXLAN-related events, such as tunnel establishment and traffic forwarding.
Checking VTEP-to-VTEP Connectivity
To check VTEP-to-VTEP connectivity at the network layer, use the following command:
ping vxlan <remote VTEP IP>
This command will send a ping request to the remote VTEP to ensure that the network path is active and reachable.
Verifying ARP Table for VXLAN
To verify ARP entries for VXLAN:
show arp
This shows the ARP table entries for VXLAN and can help identify ARP issues or mismatches that could cause VXLAN traffic to fail.
Verifying VXLAN with BGP Multicast
If using VXLAN with multicast for BGP, you can check multicast group membership:
show ip mroute
This will show multicast routing information and verify if multicast is functioning correctly for VXLAN.
Checking VRF for VXLAN
If VXLAN is configured within a VRF, use the following command to show VRF-specific VXLAN information:
show vrf VXLAN
This command displays VRF-specific VXLAN details, including interfaces, IP addresses, and routing information.
Monitoring VXLAN Traffic Flow
For monitoring traffic flows across VXLAN, the `flow-collector` command is useful:
show flow-collector vxlan
This command will display VXLAN-related traffic flow information, which is helpful in diagnosing performance or congestion issues in the VXLAN network.
