Brocade Multi-Service IronWare Switching Configuration Guide (Supporting R05.6.00) User Manual
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Multi-Service IronWare Switching Configuration Guide
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Tunnel statistics for a GRE tunnel or IPv6 manual tunnel
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NOTE
The configuration is not recommended for all users, it is only needed if the user wants to override
the default behavior.
When the GRE encapsulated multicast packet is received, hardware processing attempts to find a
match in the CAM session based on the inner (s,g) entry. If hardware processing cannot find the
inner (s,g) entry in the CAM session, the packet will be dropped. If the ip pim tunnel rpf-strict
command is configured on a GRE tunnel interface, hardware processing will check on the (s,g)
entry, and verify that the packet matches the physical port on the GRE tunnel interface, and the
GRE tunnel vlan id.
To limit a specific port to accept the (s,g) GRE tunnel traffic, enter the following command.
Brocade(config)#interface tunnel 20
Brocade(config-tnif-20)#ip pim tunnel rpf-strict
Syntax: [no] ip pim tunnel [rpf-strict]
The rpf-strict option allows you to set the strict rpf check on the multicast entry.
Tunnel statistics for a GRE tunnel or IPv6 manual tunnel
At a global level, you can enable the collection of statistics for generic routing encapsulation (GRE)
tunnels and manual IPv6 tunnels. With this feature, the Brocade device collects the statistics for
GRE and IPv6 manual tunnels and displays packet counters for tunnels at the management
processor (MP). This feature collects and displays unicast and multicast packets over both
directions of the tunnels.
Statistics collection is not enabled by default, so you need to enter the IP tunnel policy
configuration level and then issue the accounting-enable command to start collecting the statistics
for GRE and IPv6 manual tunnels. This procedure is described in
page 724. This required preliminary ensures that the source-ingress CAM partition is not allocated
unless statistics collection or tunnel session enforcement checks are actually needed. (Because
the statistics enable does not enforce the GRE and IPv6 tunnel session checks by default, these
capabilities have their own enable commands in the IP tunnel policy CLI level. The applicable
commands are described in
“Configuring IPv6 session enforce check”
“Configuring IPv6 session enforce check”
on page 725.) You can view examples of related show
command output in
“Displaying GRE and manual IPv6 tunnel statistics”
The remainder of this introduction to tunnel statistics describes reload behavior for certain
commands and detailed notes and restrictions that apply to the support for tunnel statistics.
Reload behavior and the source-ingress CAM partition
When one of the three tunnel-related commands is configured at the CLI level for IP tunnel policy
(entered by use of the ip-tunnel-policy command), you might need to save the configuration and
reload the device to create the required source-ingress-CAM partition. If the memory write and
reload are needed, the system prompts for these steps after you finish the enable commands. The
condition for which you might need to write and reload is the absence of the source-ingress-CAM
partition. If this partition does not exist, the first time that you run either the
gre-session-enforce-check, ipv6-session-enforce-check, or accounting-enable command, the