Cisco GRS User Manual

•
Setting 6rd Tunnel Path MTU
◦
By default the 6rd Tunnel MTU value is 1280.
service cgn demo
service-type tunnel v6rd 6rd1
path-mtu 1480
commit
•
Enabling reassembly of Fragmented Tunnel Packets.
•
Fragmented Tunneled IPv4 packets are reassembled by BR before decapsulation.
service cgn demo
service-type tunnel v6rd 6rd1
reassembly-enable
commit
RP/0/RP0/CPU0:BR1#show cgn tunnel v6rd 6rd1 statistics
Incoming fragments count : 2
Reassembled packet count : 1
Reassembled fragments count : 2
ICMP incoming fragments count : 0
Total fragment drop count : 0
Fragments dropped due to timeout : 0
Duplicate fragments drop count : 0
No DB entry fragments drop count : 0
Fragments dropped due to security check failure : 0
Insufficient IPv4 payload fragment drop count : 0
Unsupported protocol fragment drops : 0
Invalid IPv6 prefix fragment drop count : 0
Incoming ICMP fragment count : 0
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ICMP Throttling
◦
By default CGSE throttles 1 per core ( we have 64 cores in CGSE)
RP/0/RP0/CPU0:BR1#config
RP/0/RP0/CPU0:BR1(config)#service cgn cgn1
RP/0/RP0/CPU0:BR1(config-cgn)#protocol icmp rate-limit ?
<0-65472> ICMP rate limit per second, should be multiple of 64
commit
•
Reset DF bit
◦
Tunneled IPv4 packets from BR will have DF bit reset (0) which will allow fragmentation in the
path to RG.
◦
By default it is set to 1 to support Anycast routing
service cgn demo
service-type tunnel v6rd 6rd1
reset-df-bit
commit
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Additional Information:
◦ IPv6 Rapid Deployment on IPv4 Infrastructures (6rd) – http://tools.ietf.org/html/rfc5969
◦
ICMPv4 to ICMPv6 Translation as per http://tools.ietf.org/html/draft-ietf-behave-v6v4-xlate-22
◦
Basic Transition Mechanisms for IPv6 Hosts and Routers", RFC 4213, October 2005.
•
"An Anycast Prefix for 6to4 Relay Routers", RFC 3068, June 2001.
• “Security Considerations for 6to4", RFC 3964, December 2004.
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Implementing Carrier Grade NAT on Cisco IOS XR Software
Configuring IPv6 Rapid Development

Cisco GRS Specifications

General

Brand	Cisco
Model	GRS
Category	Network Router
Language	English