BigIron RX Series Configuration Guide 107553-1001986-01Configuring IPv6 ICMP 43BigIron RX# show ipv6Global Settingsunicast-routing enabled, hop-limit 64No Inbound Access List SetNo Outbound Access List SetPrefix-based IPv6 Load-sharing is Enabled, Number of load share paths: 4Syntax: show ipv6You can display the entries in the IPv6 forwarding cache; for example:Syntax: show ipv6 cache [<index-number> | <ipv6-prefix>/<prefix-length> | <ipv6-address> |ethernet <port> | ve <number> | tunnel <number>]Configuring IPv6 ICMPAs with the Internet Control Message Protocol (ICMP) for IPv4, ICMP for IPv6 provides error andinformational messages. Brocade’s implementation of the stateless autoconfiguration, neighbordiscovery, and path MTU discovery features use ICMP messages.This section explains how to configure the following IPv6 ICMP features:• ICMP rate limiting.• ICMP redirects.Configuring ICMP rate limitingYou can limit the rate at which IPv6 ICMP error messages are sent out on a network. IPv6 ICMPimplements a token bucket algorithm.To illustrate how this algorithm works, imagine a virtual bucket that contains a number of tokens.Each token represents the ability to send one ICMP error message. Tokens are placed in the bucketat a specified interval until the maximum number of tokens allowed in the bucket is reached. Foreach error message that ICMP sends, a token is removed from the bucket. If ICMP generates aseries of error messages, messages can be sent until the bucket is empty. If the bucket is empty oftokens, error messages cannot be sent until a new token is placed in the bucket.You can adjust the following elements related to the token bucket algorithm:• The interval at which tokens are added to the bucket. The default is 100 milliseconds.• The maximum number of tokens in the bucket. The default is 10 tokens.BigIron RX# show ipv6 cacheTotal number of cache entries: 10IPv6 Address Next Hop Port1 5000:2::2 LOCAL tunnel 22 2000:4::106 LOCAL ethe 23 2000:4::110 DIRECT ethe 24 2002:c0a8:46a::1 LOCAL ethe 25 fe80::2e0:52ff:fe99:9737 LOCAL ethe 26 fe80::ffff:ffff:feff:ffff LOCAL loopback 27 fe80::c0a8:46a LOCAL tunnel 28 fe80::c0a8:46a LOCAL tunnel 69 2999::1 LOCAL loopback 210 fe80::2e0:52ff:fe99:9700 LOCAL ethe 1
