The Arista Multicast Source Discovery Protocol (MSDP) router must be configured to use its loopback address as the source address when originating MSDP traffic.

Severity	Group ID	Group Title	Version	Rule ID	Date	STIG Version
low	V-256056	SRG-NET-000512-RTR-000011	ARST-RT-000770	SV-256056r991795_rule	2025-02-20	2

Description
Using a loopback address as the source address offers a multitude of uses for security, access, management, and scalability of MSDP routers. It is easier to construct appropriate ingress filters for router management plane traffic destined to the network management subnet since the source addresses will be from the range used for loopback interfaces instead of a larger range of addresses used for physical interfaces. Log information recorded by authentication and syslog servers will record the router's loopback address instead of the numerous physical interface addresses.

Description

Using a loopback address as the source address offers a multitude of uses for security, access, management, and scalability of MSDP routers. It is easier to construct appropriate ingress filters for router management plane traffic destined to the network management subnet since the source addresses will be from the range used for loopback interfaces instead of a larger range of addresses used for physical interfaces. Log information recorded by authentication and syslog servers will record the router's loopback address instead of the numerous physical interface addresses.

ℹ️ Check
Review the Arista router configuration to verify a loopback address has been configured. Verify a loopback interface is used as the source address for all MSDP packets generated by the router. Execute the command "sh run sec router msdp". router#show running-config \| section router msdp router msdp originator-id local-interface Loopback0 If the Arista router does not use its loopback address as the source address when originating MSDP traffic, this is a finding.

ℹ️ Check

Review the Arista router configuration to verify a loopback address has been configured. Verify a loopback interface is used as the source address for all MSDP packets generated by the router. Execute the command "sh run sec router msdp". router#show running-config | section router msdp router msdp originator-id local-interface Loopback0 If the Arista router does not use its loopback address as the source address when originating MSDP traffic, this is a finding.

✔️ Fix
Ensure the Arista router originator-id is the source address loopback0 for originating traffic. router(config)#router msdp router (config-router-msdp)#originator-id local-interface loopback0 router (config-router-msdp)#exit