Brocade Communications Systems Upgrade Pef IPMC5000PEF IPMC5000PEF Manual De Usuario

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If more than one router has the same DR priority on a subnet (as in the case of default DR priority
on all), the router with the numerically highest IP address on that subnet will get elected as the DR.
The DR priority information is used in the DR election only if all the PIM routers connected to the
subnet support the DR priority option. If there is at least one PIM router on the subnet that does not
support this option, then the DR election falls back to the backwards compatibility mode in which
the router with the numerically highest IP address on the subnet is declared the DR regardless of
the DR priority values.
Passive Multicast Route Insertion
To prevent unwanted multicast traffic from being sent to the CPU, IPv6 PIM routing and Passive
Multicast Route Insertion (PMRI) can be used together to ensure that multicast streams are only
forwarded out ports with interested receivers and unwanted traffic is dropped in hardware on Layer 3
routers.
PMRI enables a Layer 3 switch running IPv6 PIM Sparse to create an entry for a multicast route (for
example, (S,G)), with no directly attached clients or when connected to another PIM router (transit
network).
When a multicast stream has no output interfaces, the Layer 3 switch can drop packets in hardware if
the multicast traffic meets the following conditions in IPv6 PIM-SM.
The route has no OIF.
The directly connected source passes source RPF check and completes data registration with the
RP, or the non-directly connected source passes source RPF check.
If the OIF is inserted after the hardware-drop entries are installed, the hardware entries will be updated
to include the OIFs.
NOTE
Disabling hardware-drop does not immediately take away existing hardware-drop entries, they will go
through the normal route aging processing when the traffic stops.
Configuring PMRI
PMRI is enabled by default. To disable PMRI, enter the following commands.
device(config)# ipv6 router pim
device(config-ipv6-pim-router)# hardware-drop-disable
To disable PMRI for a specified VRF, enter the commands as shown in the following example.
device(config)# ipv6 router pim vrf blue
device(config-ipv6-pim-router-vrf-blue)# hardware-drop-disable
Syntax: [no] hardware-drop-disable
Displaying hardware-drop
Use the show ipv6 pim sparse command to display if the hardware-drop feature has been enabled or
disabled.
Brocade# show ipv6 pim sparse 
Global PIM Sparse Mode Settings
  Maximum Mcache         : 4096        Current Count              : 7
  Hello interval         : 30          Neighbor timeout           : 105
Passive Multicast Route Insertion
FastIron Ethernet Switch IP Multicast Configuration Guide
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