Operating Rules And Recommendations - HP ProCurve 6200yl Multicast And Routing Manual

PIM-SM (Sparse Mode)

Operating Rules and Recommendations

Operating Rules and Recommendations

Guideline for Configuring Candidate RPs and BSRs. Routers in a PIM­
SM domain should usually be configured as both candidate RPs and candidate
BSRs. Doing so can reduce some overhead traffic.
The Shortest-Path-Tree (SPT) Policy Should Be the Same for All RPs
in a Domain. Allowing some RPs to remain configured to implement STPs
while configuring other RPs in the same domain to force RPT use can result
in unstable traffic flows. (Use the [ no ] ip pim-sparse spt-threshold command to
change between SPT and RPT operation on each router.)
Application of RPs to Multicast Groups. In a PIM-SM domain, a given
multicast group or range of groups can be supported by only one RP. (Typically,
multiple candidate RPs in a domain are configured with overlapping coverage
of multicast groups, but only one such candidate will be elected to support a
given group.)
Ensuring that the Candidate RPs in a PIM-SM Domain Cover All
Desired Multicast Groups. All of the multicast groups you want to allow
in a given PIM-SM domain must be included in the aggregate of the multicast
groups configured in the domain's candidate RPs. In most cases, all C-RPs in
a domain should be configured to support all RP groups (the default configu­
ration for a router enabled as a C-RP). This provides redundancy in case an
RP becomes unavailable. (If the C-RP supporting a particular multicast group
becomes unavailable, another C-RP is elected to support the group as long as
there is redundancy in the C-RP configuration for multiple routers. Note that
in cases where routers are statically configured to support a specific group or
range of groups, the C-RP prioritization mechanism allows for redundant
support.
PIM-SM and PIM-DM. These two features cannot both be enabled on the
same router at the same time.
Supporting PIM-SM Across a PIM Domain. To properly move multicast
traffic across a PIM-SM domain, all routers in the domain must be configured
to support PIM-SM. That is, a router without PIM-SM capability blocks routed
multicast traffic in a PIM-SM domain.
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