Configuring MLD Limit
Context
As defined, multicast members can join or leave a multicast group at any time and any place, and the number of members is not limited. When many users watch multiple programs simultaneously, a lot of bandwidth on the multicast device is consumed, leading to degradation of device performance. To prevent this problem, you can configure Multicast Listener Discovery (MLD) limit on the multicast router to limit the number of multicast groups on an interface or in the system. This ensures that users watch clear, stable programs. When the multicast router receives a Multicast Listener Report message, the router first checks whether the number of multicast groups exceeds the maximum value if the new multicast group is added. If not, the multicast member is added to the multicast group and the multicast data is forwarded to the member.
- Counts each (*, G) entry as one entry.
- Counts each (S, G) entry as one entry.
- Counts each (*, G) entry used in MLD SSM mapping as one entry but does not count (S, G) entries converted from (*, G) entries.
- You can configure the maximum number of MLD multicast members in the system and MLD views. If the configurations in the system and MLD views are both performed, the smaller value takes effect.
- To configure MLD limit in the system and interface views of the router, you are advised to set a larger maximum number of MLD multicast members in the system view.