The Arista MLS layer 2 switch must have the default VLAN pruned from all trunk ports that do not require it.
An XCCDF Rule
Description
<VulnDiscussion>The default VLAN (i.e., VLAN 1) is a special VLAN used for control plane traffic such as Spanning-Tree Protocol (STP), Dynamic Trunking Protocol (DTP), VLAN Trunking Protocol (VTP), and Port Aggregation Protocol (PAgP). VLAN 1 is enabled on all trunks and ports by default. With larger campus networks, care needs to be taken about the diameter of the STP domain for the default VLAN. Instability in one part of the network could affect the default VLAN, thereby influencing control-plane stability and therefore STP stability for all other VLANs.</VulnDiscussion><FalsePositives></FalsePositives><FalseNegatives></FalseNegatives><Documentable>false</Documentable><Mitigations></Mitigations><SeverityOverrideGuidance></SeverityOverrideGuidance><PotentialImpacts></PotentialImpacts><ThirdPartyTools></ThirdPartyTools><MitigationControl></MitigationControl><Responsibility></Responsibility><IAControls></IAControls>
- ID
- SV-255982r991776_rule
- Severity
- Medium
- References
- Updated
Remediation - Manual Procedure
Best practice for VLAN-based networks is to configure Arista MLS switch to prune unnecessary trunk links from gaining access to the default VLAN and ensure frames belonging to the default VLAN do not traverse trunks not requiring frames from the VLAN.
Step 1: Configure the Arista MLS switch to ensure VLAN1 is pruned from all trunk and access ports that do not require it by using the following commands:
switch(config)#vlan 1
switch(config-vlan-1)#show active