multicast ttl-check disable
Function
The multicast ttl-check disable command disables a switch from checking the TTL value of multicast packets.
The undo multicast ttl-check disable command enables a switch to check the TTL value of multicast packets again.
By default, a switch checks the TTL value of multicast packets.
This command is supported only on the following models: S5720-HI, S5730-HI, S5731-H, S5731-S, S5731S-H, S5731S-S, S5732-H, S6720-HI, S6730-H, S6730S-H, S6730-S, and S6730S-S.
Usage Guidelines
In V200R019C10 and later versions, when multicast packets between a multicast source and receiver are forwarded across VLANs, the multicast packets with a TTL value less than or equal to 1 will be discarded by default.
In versions earlier than V200R019C10, S5720-HI, S5730-HI, S5731-H, S5731-S, S5731S-H, S5731S-S, S5732-H, S6720-HI, S6730-H, S6730S-H, S6730-S, and S6730S-S do not discard multicast packets whose TTL value is less than or equal to 1. After the switch software version is upgraded to V200R019C10 or later, however, if you want a switch not to discard multicast packets whose TTL value is less than or equal to 1, run the multicast ttl-check disable command to disable the switch from checking the TTL value of multicast packets.
The multicast ttl-check disable command does not apply to the following scenarios:
- This command is not applicable to multicast packets on a VPN. A switch always discards multicast packets on a VPN if their TTL value is less than or equal to 1.
- This command does not apply when a multicast source and receiver are in the same VLAN, in which case, the switch does not check the TTL value of multicast packets between them.
- When the forwarding mode of multicast packets is changed to MAC address-based forwarding, the switch does not check the TTL value of multicast packets.