Scenario:

A medium-sized data center was experiencing connectivity issues between servers connected to Arista switches, using Multi-Chassis Link Aggregation (MLAG) and Virtual Port Channel (vPC) for redundancy. The data center leveraged Arista CloudVision Portal (CVP) for network management and VXLAN for overlay networking. The IT team needed to identify the root cause and implement a solution to restore server connectivity and network performance.

Background:

The data center network used Arista switches with MLAG and Cisco Nexus switches with vPC to provide redundant paths and load balancing between servers. Arista CVP was employed for managing and monitoring the network, while VXLAN provided a flexible overlay solution for network segmentation and scalability.

Actions:

1. Identifying the Affected Servers and Network Devices:

The IT team first identified the servers and network devices affected by the connectivity issues, gathering relevant information such as IP addresses, VLANs, and MLAG/vPC configurations.

2. Analyzing Network Topology and Configuration:

The team used Arista CVP to review the MLAG and vPC configurations on the affected switches, as well as the VXLAN configuration for the overlay network.

3. Identifying MLAG/vPC Misconfigurations:

Upon further investigation, the team discovered inconsistencies in the MLAG and vPC configuration between Arista and Cisco switches, causing intermittent connectivity issues between the servers.

Configuration adjustments:

To resolve the MLAG and vPC misconfiguration issues, the IT team performed the following steps on the affected switches:

a. On the Arista switches, they accessed the MLAG configuration using the Command Line Interface (CLI):

Arista> enable
Arista# configure terminal

b. They corrected the MLAG settings by modifying the MLAG configuration on the Arista switches:

Arista(config)# mlag configuration
Arista(config-mlag)# domain-id [DOMAIN_ID]
Arista(config-mlag)# local-interface [INTERFACE_NAME]
Arista(config-mlag)# peer-address [PEER_IP_ADDRESS]
Arista(config-mlag)# peer-link [PORT_CHANNEL_NAME]

c. On the Cisco Nexus switches, they accessed the vPC configuration:

Nexus> enable
Nexus# configure terminal

d. They corrected the vPC settings by modifying the vPC configuration on the Cisco switches:

Nexus(config)# vpc domain [DOMAIN_ID]
Nexus(config-vpc-domain)# role priority [PRIORITY_VALUE]
Nexus(config-vpc-domain)# peer-keepalive destination [PEER_IP_ADDRESS]
Nexus(config-vpc-domain)# peer-link port-channel [PORT_CHANNEL_NUMBER]

4. Validating the Solution:

After implementing the configuration changes, the IT team tested server connectivity to ensure that the issues were resolved. They observed improved connectivity and network performance across the data center.

5. Documenting and Sharing:

The team documented the issue, solution, and configuration changes to share their findings with the team and prevent similar issues in the future.

Conclusion:

By identifying and addressing the root cause of server connectivity issues in the data center network, the IT team ensured optimal network performance and improved redundancy. This example highlights the importance of consistent MLAG and vPC configuration in maintaining a reliable and efficient data center network with mixed-vendor environments.