H3C Technologies H3C S3600 Series Switches - Manual (Page 423)

4-18
Upon receiving a prune message from a downstream device, the upstream node removes the interface
connecting the downstream node from the outgoing interface list of the (S, G) entry. If the downstream
node finds shortly after it has sent a prune message that a member for the multicast group is present on
the local subnet, it immediately sends a prune override message to the upstream to let the upstream
node cancel the prune action.
The S3600 series Ethernet switches support prune delay configuration. Upon receiving a prune
message from a downstream node, the upstream node does not take a prune action immediately;
instead, it maintains the forwarding state of the interface to the downstream. If the upstream node
receives a prune override message from the downstream node within the prune delay interval, it
cancels the prune action; otherwise, it prunes the interface to the downstream when the prune delay
times out.
An appropriate PIM prune delay setting can reduce the number of prune/graft operations to
downstream nodes and thus lessen the burden to the device itself and the network.
Follow these steps to configure PIM prune delay:
To do… Use the command… Remarks
Enter system view system-view —
Enter PIM view pim —
Configure the PIM
prune delay interval
prune delay interval
Optional
5 seconds by default
Clearing the Related PIM Entries
You can execute the reset command in user view to clear the related statistics about multicast PIM.
Follow these steps to clear the related PIM entries:
To do... Use the command... Remarks
Clear PIM route
entries
reset pim routing-table { all | { group-address [ mask
{ mask-length | mask } ] | source-address [ mask
{ mask-length | mask } ] | incoming-interface
interface-type interface-number } * }
Clear PIM neighbors
reset pim neighbor { all | { neighbor-address | interface
interface-type interface-number } * }
Perform the
configuration in
user view.
Displaying and Maintaining PIM
Configuration Use the command... Remarks
Display PIM multicast routing
tables
display pim routing-table [ { { *g
[ group-address [ mask { mask-length |
mask } ] ] | **rp [ rp-address [ mask
{ mask-length | mask } ] ] } | { group-address
[ mask { mask-length | mask } ] |
source-address [ mask { mask-length |
mask } ] } * } | incoming-interface
{ interface-type interface-number | null } |
{ dense-mode | sparse-mode } ] *
Available in
any view