set igmp header-validation

This command enables header validation for IGMP (Internet Group Management Protocol) messages.

When header validation is enabled, IGMP Snooping checks:

  • The time-to-live (TTL) field in the IGMP header and drops packets where TTL is not equal to 1. The TTL field should always be set to 1 in the headers of IGMP reports and queries.
  • The presence of the router alert option (9404) in the IP packet header of the IGMPv2 message and drops packets that do not include this option.
  • The presence of the router alert option (9404) and ToS Byte = 0xC0 (Internet Control) in the IP packet header of IGMPv3 message and drops packets that do not include these options.
    Default Enabled
    Format set igmp header-validation
    Mode Global Config