The Arista router must be configured to advertise a hop limit of at least 32 in Router Advertisement messages for IPv6 stateless auto-configuration deployments.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-256057	ARST-RT-000780	SV-256057r882513_rule		Low

Description
The Neighbor Discovery protocol allows a hop limit value to be advertised by routers in a Router Advertisement message being used by hosts instead of the standardized default value. If a very small value was configured and advertised to hosts on the LAN segment, communications would fail due to the hop limit reaching zero before the packets sent by a host reached its destination.

STIG	Date
Arista MLS EOS 4.2x Router Security Technical Implementation Guide	2023-01-17

Details

Check Text ( C-59733r882511_chk )
This requirement is not applicable for the DODIN backbone. Review the Arista router configuration to determine if the hop limit has been configured for Router Advertisement messages. Execute the command "sh run | section hop-limit". interface Ethernet3 ipv6 nd ra hop-limit 32 If the router has been configured and has not been set to at least 32, this is a finding.

Fix Text (F-59676r882512_fix)
This requirement is not applicable for the DODIN backbone. Configure the Arista router to advertise a hop limit of at least 32 in Router Advertisement messages. LEAF-1A(config-if-Et3)#interface ethernet 3 LEAF-1A(config-if-Et3)#ipv6 nd ra hop-limit 32