Administrator Guide
Protocol Ethernet Address
RIP 01:00:5e:00:00:09
NTP 01:00:5e:00:01:01
VRRP 01:00:5e:00:00:12
PIM-SM 01:00:5e:00:00:0d
• The Dell EMC Networking OS implementation of MTRACE is in accordance with IETF draft draft-fenner-traceroute-ipm.
• Multicast is not supported on secondary IP addresses.
• If you enable multicast routing, egress Layer 3 ACL is not applied to multicast data trac.
• Multicast trac can be forwarded to a maximum of 15 VLANs with the same outgoing interface.
Dell EMC Networking OS does not support multicast routing in the following VLT scenarios:
• In a VLT enabled PIM router, multicast routing is not supported when there are multiple PIM spanned paths to reach source or RP. The
workaround is to congure only one PIM spanned path to reach any PIM router in the aggregation or spine.
• If a source is connected to a non-spanned interface of the VLT peer nodes and the RP is reachable on a spanned interface from both
the VLT nodes, there is a possibility to receive duplicate trac on the source. To avoid this, you should congure the source to be
reachable on a spanned interface.
Multicast Policies
The Dell EMC Networking OS supports multicast features for IPv4.
IPv4 Multicast Policies
The following sections describe IPv4 multicast policies.
• Limiting the Number of Multicast Routes
• Preventing a Host from Joining a Group
• Preventing a PIM Router from Forming an Adjacency
• Preventing a Source from Registering with the RP
• Preventing a PIM Router from Processing a Join
Limiting the Number of Multicast Routes
When the total number of multicast routes on a system limit is reached, the Dell EMC Networking OS does not process Internet group
management protocol (IGMP) or multicast listener discovery protocol (MLD) joins to protocol-independent multicast (PIM) — though it
still processes leave messages — until the number of entries decreases below 95% of the limit.
When the limit falls below 95% after hitting the maximum, the system begins relearning route entries through IGMP, MLD, and multicast
source discovery protocol (MSDP).
• If you increase the limit after it is reached, subsequent join requests are accepted. In this case, increase the limit by at least 10% for
IGMP and MLD to resume.
• If you decrease the limit after it is reached, the Dell EMC Networking OS does not clear the existing sessions. Entries are cleared after a
timeout (you may also clear entries using the clear ip mroute command).
NOTE
: The Dell EMC Networking OS waits at least 30 seconds between stopping and starting IGMP join processing. You may
experience this delay when manipulating the limit after it is reached.
When the multicast route limit is reached, the following displays:
3w1d13h: %RPM0-P:RP2 %PIM-3-PIM_TIB_LIMIT: PIM TIB limit reached. No new routes will
be learnt until TIB level falls below low watermark.
Multicast Features
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