The Arista MLS layer 2 switch must have Dynamic Address Resolution Protocol (ARP) Inspection (DAI) enabled on all user VLANs.
An XCCDF Rule
Description
<VulnDiscussion>DAI intercepts Address Resolution Protocol (ARP) requests and verifies that each of these packets has a valid IP-to-MAC address binding before updating the local ARP cache and before forwarding the packet to the appropriate destination. Invalid ARP packets are dropped and logged. DAI determines the validity of an ARP packet based on valid IP-to-MAC address bindings stored in the DHCP snooping binding database. If the ARP packet is received on a trusted interface, the switch forwards the packet without any checks. On untrusted interfaces, the switch forwards the packet only if it is valid.</VulnDiscussion><FalsePositives></FalsePositives><FalseNegatives></FalseNegatives><Documentable>false</Documentable><Mitigations></Mitigations><SeverityOverrideGuidance></SeverityOverrideGuidance><PotentialImpacts></PotentialImpacts><ThirdPartyTools></ThirdPartyTools><MitigationControl></MitigationControl><Responsibility></Responsibility><IAControls></IAControls>
- ID
- SV-255975r882267_rule
- Severity
- Medium
- References
- Updated
Remediation - Manual Procedure
Configure the Arista MLS switch to have static Address Resolution Protocol (ARP) Inspection to be enabled on all user VLANs.
By default, Arista MLS switch static ARP Inspection is disabled on all VLANs. Static ARP inspection can be enabled on all specific user VLANs by using the following command:
switch(config)#ip arp inspection vlan <vlan-list>