712 | Multicast Featuresw w w . d e l l . c o m | s u p p o r t . d e l l . c o mMulticast PoliciesFTOS offers parallel Multicast features for IPv4 and IPv6.• IPv4 Multicast Policies on page 712• IPv6 Multicast Policies on page 717IPv4 Multicast Policies• Limit the Number of Multicast Routes on page 712• Prevent a Host from Joining a Group on page 713• Rate Limit IGMP Join Requests on page 715• Prevent a PIM Router from Forming an Adjacency on page 715• Prevent a Source from Registering with the RP on page 715• Prevent a PIM Router from Processing a Join on page 717Limit the Number of Multicast RoutesWhen the limit is reached, FTOS does not process any IGMP or MLD joins to PIM—though it stillprocesses leave messages—until the number of entries decreases below 95% of the limit. When the limitfalls below 95% after hitting the maximum, the system begins relearning route entries through IGMP,MLD, and MSDP.• If the limit is increased after it is reached, join subsequent join requests are accepted. In this case, youmust increase the limit by at least 10% for IGMP and MLD to resume.• If the limit is decreased after it is reached, FTOS does not clear the existing sessions. Entries arecleared upon a timeout (you may also clear entries using clear ip mroute).When the multicast route limit is reached, FTOS displays Message 1.Task Command Syntax Command ModeLimit the total number of multicast routes on the system. ip multicast-limitRange: 1-50000Default: 15000CONFIGURATIONNote: FTOS waits at least 30 seconds between stopping and starting IGMP join processing. You mayexperience this delay when manipulating the limit after it is reached.Message 1 Multicast Route Limit Error3w1d13h: %RPM0-P:RP2 %PIM-3-PIM_TIB_LIMIT: PIM TIB limit reached. No new routes willbe learnt until TIB level falls below low watermark.3w1d13h: %RPM0-P:RP2 %PIM-3-PIM_TIB_LIMIT: PIM TIB below low watermark. Route learningwill begin.
