April 18, 2024

Mind of Marcuzio

Performance tuning is the art of wasting ten days to save ten seconds.

Comcast IPv6 Cisco IOS setup

Difficulty Level    
There's a bug for HTTP inspection over IPv6 in IOS 12.4, so a work-around ACL is provided.

ipv6 unicast-routing
ipv6 cef
ipv6 dhcp pool ComcastPool
 prefix-delegation pool Comcast-IPv6
 dns-server <IPv6-IP>
 domain-name internal.domain
ipv6 inspect name traffic ftp
ipv6 inspect name traffic udp
ipv6 inspect name traffic icmp

interface FastEthernet0/0
 description -{WAN}-
 ipv6 address dhcp
 ipv6 address autoconfig default
 ipv6 enable
 ipv6 traffic-filter wan-in in
 ipv6 traffic-filter wan-out out
 ipv6 verify unicast reverse-path
 ipv6 dhcp client pd Comcast-IPv6
 ipv6 inspect traffic out

interface FastEthernet0/1
 description -{LAN}-
 ipv6 address Comcast-IPv6 ::1/64
 ipv6 address autoconfig
 ipv6 enable
 ipv6 nd other-config-flag
 ipv6 dhcp server ComcastPool

ipv6 access-list wan-in
 permit icmp any any
 permit udp any any eq 546
 permit tcp any any established
 sequence 100 deny ipv6 any any

ipv6 access-list wan-out
 permit icmp any any
 permit tcp any any
 permit udp any any
 sequence 100 deny ipv6 any any

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