1 © 2011 Cisco Systems, Inc. All rights reserved. Cisco confidential.Cisco Networking Academy, US/Canada Introduction to Routing IPv6 Rick Graziani Computer

1© 2011 Cisco Systems, Inc. All rights reserved. Cisco confidential.Cisco Networking Academy, US/Canada

Introduction to Routing IPv6

Rick GrazianiComputer Networking InstructorCabrillo College

IPv6: The ProtocolReview from Introduction to IPv6


Many important differences including:

Larger Address Space

Use of Neighbor Discovery Protocol for discovery of prefix, prefix length, default gateway, duplicate address detection, and MAC address resolution.

Automatic address configuration without using DHCP (DHCPv6 is still an option)

No en route fragmentation: only the source node can fragment

Increased default MTU

Fragment OffsetFlags

Total LengthType of ServiceIHL

PaddingOptions

Destination Address

Source Address

Header ChecksumProtocolTime to Live

Identification

Version

Next Header Hop Limit

Flow LabelTraffic Class

Destination Address

Source Address

Payload Length

Version

Field’s Name Kept from IPv4 to IPv6

Fields Not Kept in IPv6

Name and Position Changed in IPv6

New Field in IPv6Leg

end

IPv4 IPv6


IPv6 Address Notation

128-bit IPv6 addresses are represented in:

Eight 16-bit segments

Hexadecimal (non-case sensitive) between 0000 and FFFF

Separated by colons

Example:

3ffe:1944:0100:000a:0000:00bc:2500:0d0b

One Hex digit = 4 bits


Rule 1: Leading 0’s

Two rules for reducing the size of written IPv6 addresses.

The first rule is:

The leading zeroes in any 16-bit segment do not have to be written.

Example

3ffe : 1944 : 0100 : 000a : 0000 : 00bc : 2500 : 0d0b

3ffe : 1944 : 100 : a : 0 : bc : 2500 : d0b


Rule 2: Double colon :: equals 0000…0000

The second rule can reduce this address even further:

Any single, contiguous string of one or more 16-bit segments consisting of all zeroes can be represented with a double colon.

ff02 : 0000 : 0000 : 0000 : 0000 : 0000 : 0000 : 0005

ff02 : 0 : 0 : 0 : 0 : 0 : 0 : 5

ff02 : : 5

ff02::5


Network Prefixes

IPv4, the prefix—the network portion of the address—can be identified by a dotted decimal netmask or bitcount.

255.255.255.0 or /24

IPv6 prefixes are always identified by bitcount (prefix length).

Prefix length notation:

3ffe:1944:100:a::/64

16 32 48 64 bits


All 0’s IPv6 Address

All zeroes IPv6 address can be written with a double colon ::

There are two cases where an all-zeroes address is used.

1. Default address, address is all zeroes and the prefix length is zero:

::/0

2. Unspecified address, which is used in some Neighbor Discovery Protocol procedures (later).

An unspecified address is a filler, indicating the absence of a real IPv6 address.

When writing an unspecified address, it is differentiated from a default address by its prefix length:

::/128


IPv6 Loopback Address

Equivalent to 127.0.0.1 in IPv4

This address is used when a host talks to itself.

Loopback or Local Host Address

0:0:0:0:0:0:0:1/128

or

::1/128


Interface Identifiers in IPv6 Addresses

In IPv6, a link is a network medium over which network nodes communicate using the link layer.

Interface identifiers (IDs) in IPv6 addresses:

Used to identify a unique interface on a link

Thought of as the “host portion” of an IPv6 address.

64 bits: To support both 48 bit and 64 bit IEEE MAC addresses

Required to be unique on a link

Subnets using auto addressing must be /64s.

There may be an option for DHCP and static subnets.

Static or Dynamic (next)


Automatic EUI-64 option for Ethernet Interface ID

3BA7:94FF:FE07:CBD0

Example coming soon!

Determined from Neighbor Discovery Router Advertisement (autoconfig) or statically (eui-64)


Three types of IPv6 Addresses The three types of IPv6 address follow:

1. Unicast

Global Unicast

Globally unique

Routed globally with no modification

Link Local Unicast

Unique Local Address

2. Multicast

3. Anycast

Unlike IPv4, there is no IPv6 broadcast address.

There is, however, an "all nodes" multicast address, which serves essentially the same purpose as a broadcast address.


IPv6 Address Typeshttp://www.ripe.net/lir-services/resource-

management/ipv6/ipv6-address-types


Prefix Designation and Explanation

IPv4 Equivalent

2000::/3 Global UnicastOther than the exceptions documented in this table, the operators of networks using these addresses can be found using the

Whois servers of the RIRs listed in the registry at:http://www.iana.org/assignments/ipv6-unicast-address-assignments

No equivalent single block

ff00::/8

Example: ff01:0:0:0:0:0:0:2

MulticastThese addresses are used to identify multicast groups.

They should only be used as destination addresses, never as source addresses.

224.0.0.0/4


Prefix Designation and Explanation

IPv4 Equivalent

fe80::/10

Example: fe80::200:5aee:feaa:20a2

Link-Local AddressesThese addresses are used on a single link or a non-routed common access network, such as an Ethernet LAN.

They do not need to be unique outside of that link.

Link-local addresses may appear as the source or destination of an IPv6 packet.

Routers must not forward IPv6 packets if the source or destination contains a link-local address.

169.254.0.0/16


Link-Local Scope Multicast Addresses


Subnetting IPv6

A typical IPv6 site prefix will be /48

This creates a 16 bit subnet part of the address structure

Allows for 216, or 65,536, subnets!

There are no concerns about needing an all 0’s or all 1’s subnet in IPv6!

64 bit host field allows for 264 hosts per subnet.

More than 1,000,000,000,000,000,000 addresses per subnet.

Allows of the automatic IPv6 address assignment features to work well (later).

2340:1111:AAAA::/48


Subnetting IPv6

4 specific subnets to be used inside Company1:

2340:1111:AAAA:0001::/64

2340:1111:AAAA:0002::/64

2340:1111:AAAA:0003::/64

2340:1111:AAAA:0004::/64

Note: A valid abbreviation is to remove the 3 leading 0’s from the first shown quartet.

2340:1111:AAAA:1::/64

/64


Preparing an IPv6 Addressing Plan

ripe.net/training/material/IPv6-for-LIRs-Training.../IPv6_addr_plan4.pdf

Routing IPv6


IPv6 Routing Protocols

Exactly the same as IPv4 routing protocols only different.

We will only discuss the first three:

IPv6 Static routes

OSPFv3 (defined in RFC 5340, OSPF for IPv6)

EIGRP for IPv6

RIP next generation (RIPng) (defined in RFC 2080, RIPng for IPv6)

Multiprotocol Border Gateway Protocol Version 4 (MP-BGP4 or MBGP) (defined in RFC 2545, Use of BGP-4 Multiprotocol Extensions for IPv6 Inter-Domain Routing, and RFC 4760, Multiprotocol Extensions for BGP-4)

Interface Configuration


Fa0/0

Fa0/0 Fa0/0 Fa0/0

S0/0/0

DCES0/0/0

DCES0/0/0

S0/0/1

S0/0/1

DCES0/0/1

S0/0/0

S0/0/1

DCES0/1/0

DCES0/1/1

2340:1111:AAAA:0A01::/64

2340:1111:AAAA:0A02::/64

2340:1111:AAAA:0A03::/64

2340:1111:AAAA:0101::/64

2340:1111:AAAA:0102::/64

2340:1111:AAAA:0103::/64

2340:1111:AAAA:0B01::/64

2340:1111:AAAA:0B02::/64

4444:0000:0000:4001::/64

Our Topology

Using /64’s on Point-to-Point serial links just for simplicity

http://tools.ietf.org/html/rfc6164


ipv6 unicast-routing

ipv6 unicast-routing global configuration command

Enables IPv6 routing

Required before any ipv6 routing protocol can be configured

Note: We will not be discussing RIPng (RIP for IPv6)

R1(config)# ipv6 router rip luigi% IPv6 routing not enabledR1(config)# ipv6 unicast-routing R1(config)# ipv6 router rip luigiR1(config-rtr)#


Just to make life easier….R1(config)# line con 0R1(config-line)# logging synchronousR1(config-line)# exec-timeout 0 0R1(config-line)# exitR1(config)# no ip domain-lookup


R1ipv6 unicast-routing

interface FastEthernet0/0 no ip address ipv6 address 2340:1111:AAAA:101::1/64!interface Serial0/0/0 no ip address ipv6 address 2340:1111:AAAA:A01::1/64 clock rate 64000!interface Serial0/0/1 no ip address ipv6 address 2340:1111:AAAA:A03::1/64



interface FastEthernet0/0 no ip address ipv6 address 2340:1111:AAAA:102::1/64!interface Serial0/0/0 no ip address ipv6 address 2340:1111:AAAA:A01::2/64!interface Serial0/0/1 no ip address ipv6 address 2340:1111:AAAA:A02::1/64 clock rate 64000



interface FastEthernet0/0 no ip address ipv6 address 2340:1111:AAAA:103::1/64!interface Serial0/0/0 no ip address ipv6 address 2340:1111:AAAA:A03::2/64 clock rate 64000!interface Serial0/0/1 no ip address ipv6 address 2340:1111:AAAA:A02::2/64!interface Serial0/1/0 no ip address ipv6 address 2340:1111:AAAA:B01::1/64 clock rate 64000!interface Serial0/1/1 no ip address ipv6 address 2340:1111:AAAA:B02::1/64 clock rate 64000



interface FastEthernet0/0 no ip address ipv6 address 4444:0:0:4001::1/64!interface Serial0/0/0 no ip address ipv6 address 2340:1111:AAAA:B01::2/64!interface Serial0/0/1 no ip address ipv6 address 2340:1111:AAAA:B02::2/64


Verify

R1# show ip inter briefInterface IP-Address OK? Method Status ProtocolFastEthernet0/0 unassigned YES unset up up

FastEthernet0/1 unassigned YES unset administratively down down

Serial0/0/0 unassigned YES unset up up

Serial0/0/1 unassigned YES unset up up

R1#

R1# show ipv6 inter briefFastEthernet0/0 [up/up] FE80::21B:CFF:FEC2:82D8 2340:1111:AAAA:101::1FastEthernet0/1 [administratively down/down]Serial0/0/0 [up/up] FE80::21B:CFF:FEC2:82D8 2340:1111:AAAA:A01::1Serial0/0/1 [up/up] FE80::21B:CFF:FEC2:82D8 2340:1111:AAAA:A03::1R1#


Verify

R1 #ping 2340:1111:AAAA:0A01::2

Type escape sequence to abort.Sending 5, 100-byte ICMP Echos to 2340:1111:AAAA:A01::2, timeout is 2

seconds:!!!!!Success rate is 100 percent (5/5), round-trip min/avg/max = 28/28/28 msR1#


VerifyR1# debug ipv6 packetIPv6 unicast packet debugging is onR1# ping 2340:1111:AAAA:0A01::2

Type escape sequence to abort.Sending 5, 100-byte ICMP Echos to 2340:1111:AAAA:A01::2, timeout is 2

seconds:!!!!!Success rate is 100 percent (5/5), round-trip min/avg/max = 28/28/28 msR1#*Jun 19 16:19:13.181: IPv6: SAS picked source 2340:1111:AAAA:A01::1 for

2340:1111:AAAA:A01::2 (Serial0/0/0)*Jun 19 16:19:13.181: IPV6: source 2340:1111:AAAA:A01::1 (local)*Jun 19 16:19:13.181: dest 2340:1111:AAAA:A01::2 (Serial0/0/0)*Jun 19 16:19:13.181: traffic class 0, flow 0x0, len 100+0, prot 58,

hops 64, originating

Jun 19 16:19:13.241: IPV6: source 2340:1111:AAAA:A01::2 (Serial0/0/0)*Jun 19 16:19:13.241: dest 2340:1111:AAAA:A01::1*Jun 19 16:19:13.241: traffic class 0, flow 0x0, len 100+4, prot 58,

hops 64, forward to ulp

R1# un all

ICMPv6


Link-local AddressesR1# show ipv6 inter briefFastEthernet0/0 [up/up] FE80::21B:CFF:FEC2:82D8 2340:1111:AAAA:101::1FastEthernet0/1 [administratively down/down]Serial0/0/0 [up/up] FE80::21B:CFF:FEC2:82D8 2340:1111:AAAA:A01::1Serial0/0/1 [up/up] FE80::21B:CFF:FEC2:82D8 2340:1111:AAAA:A03::1R1#

Scope is confined to a single link.

Uniqueness is assured only on one link.

Not routable off the link

Device can determine its own link local IPv6 address without needing to communicate with any other device

Ethernet link-local address uses MAC-address (EUI-64) for Interface ID

Considered best practice to statically configure link local address (Interface ID) on serial interfaces (later).


Link-local Addresses

R1# show inter fa 0/0FastEthernet0/0 is up, line protocol is up Hardware is MV96340 Ethernet, address is 001b.0cc2.82d8 (bia 001b.0cc2.82d8) <output omitted for brevity>

R1# show ipv6 inter fa 0/0FastEthernet0/0 is up, line protocol is up IPv6 is enabled, link-local address is FE80::21B:CFF:FEC2:82D8 No Virtual link-local address(es): Global unicast address(es): 2340:1111:AAAA:101::1, subnet is 2340:1111:AAAA:101::/64 <output omitted for brevity>

48 bit MAC Address: 001b.0cc2.82d8 0 0 1 b . 0 c c 2 . 8 2 d 8 0000 0000 0001 1011 . 0000 1100 1100 0010 . 1000 0010 1101 10000000 0000 0001 1011 . 0000 1100 11111111 11111110 1100 0010 . 1000 0010 1101 10000000 0010 0001 1011 . 0000 1100 11111111 11111110 1100 0010 . 1000 0010 1101 1000 0 2 1 b . 0 c F F F E c 2 . 8 2 d 8

link-local address is FE80::21B:CFF:FEC2:82D8


Static Link-localR1(config)# inter ser 0/0/0R1(config-if)# ipv6 add fe80::1 ? link-local Use link-local address

R1(config)# inter ser 0/0/0R1(config-if)# ipv6 add fe80::1 link-local


R1# show ipv6 inter briefFastEthernet0/0 [up/up] FE80::21B:CFF:FEC2:82D8 2340:1111:AAAA:101::1FastEthernet0/1 [administratively down/down]Serial0/0/0 [up/up] FE80::1 2340:1111:AAAA:A01::1Serial0/0/1 [up/up] FE80::1 2340:1111:AAAA:A03::1R1#

Unique on the link

Used Router Number for simplicity

R1: FE80::1


Static Link-localR2(config)# inter ser 0/0/0R2(config-if)# ipv6 add fe80::2 link-local

R2(config)# inter ser 0/0/1 R2(config-if)# ipv6 add fe80::2 link-local








R1# show ipv6 routeIPv6 Routing Table - 8 entriesCodes: C - Connected, L - Local, S - Static, R - RIP, B - BGP U - Per-user Static routeC 2340:1111:AAAA:101::/64 [0/0] via ::, FastEthernet0/0L 2340:1111:AAAA:101::1/128 [0/0] via ::, FastEthernet0/0C 2340:1111:AAAA:A01::/64 [0/0] via ::, Serial0/0/0L 2340:1111:AAAA:A01::1/128 [0/0] via ::, Serial0/0/0C 2340:1111:AAAA:A03::/64 [0/0] via ::, Serial0/0/1L 2340:1111:AAAA:A03::1/128 [0/0] via ::, Serial0/0/1L FE80::/10 [0/0] via ::, Null0L FF00::/8 [0/0] via ::, Null0R1#R1# show ipv6 inter brief<output omitted for brevity>Serial0/0/0 [up/up] FE80::1 2340:1111:AAAA:A01::1Serial0/0/1 [up/up] FE80::1 2340:1111:AAAA:A03::1

Due to the nature of link-local addresses, the specific FE80::/10 prefix (link local networks) does not appear in the routing table

L = Local not Link-local


So it is necessary to specify from which interface packets should be sourced when you ping a link-local address:

R1# ping fe80::2Output Interface: ser 0/0/0% Invalid interface. Use full interface name without spaces (e.g. Serial0/1)Output Interface: serial 0/0/0% Invalid interface. Use full interface name without spaces (e.g. Serial0/1)Output Interface: serial0/0/0 Type escape sequence to abort.Sending 5, 100-byte ICMP Echos to FE80::2, timeout is 2 seconds:Packet sent with a source address of FE80::1!!!!!Success rate is 100 percent (5/5), round-trip min/avg/max = 28/28/28 msR1#


Connected routes occur for any interface IPv6 unicast address that has more than link local scope

The local routes are all /128 routes and are essentially host routes for the router’s IPv6 unicast address.

These local routes allow the router to more efficiently process packets directed to the router itself rather than for packet directed toward connected subnets.

R2# show ipv6 routeIPv6 Routing Table - 8 entriesCodes: C - Connected, L - Local, S - Static, R - RIP, B - BGP U - Per-user Static route I1 - ISIS L1, I2 - ISIS L2, IA - ISIS interarea, IS - ISIS summary O - OSPF intra, OI - OSPF inter, OE1 - OSPF ext 1, OE2 - OSPF ext 2 ON1 - OSPF NSSA ext 1, ON2 - OSPF NSSA ext 2 D - EIGRP, EX - EIGRP externalC 2340:1111:AAAA:102::/64 [0/0] via ::, FastEthernet0/0L 2340:1111:AAAA:102::1/128 [0/0] via ::, FastEthernet0/0C 2340:1111:AAAA:A01::/64 [0/0] via ::, Serial0/0/0L 2340:1111:AAAA:A01::2/128 [0/0] via ::, Serial0/0/0C 2340:1111:AAAA:A02::/64 [0/0] via ::, Serial0/0/1L 2340:1111:AAAA:A02::1/128 [0/0] via ::, Serial0/0/1L FE80::/10 [0/0] via ::, Null0L FF00::/8 [0/0] via ::, Null0

IPv6 Routing Table… first look


The IPv6 Neighbor Table

Link-local: fe80::50a5:8a35:a5bb:66e1

2340:1111:AAAA::/642340:1111:AAAA::1/64

Global Unicast: 2340:1111:aaaa:0:50a5:8a35:a5bb:66e1

IPv6-Router# ping 2340:1111:AAAA:0:50a5:8a35:a5bb:66e1!!!!!*Mar 1 00:08:28.779: ICMPv6-ND: Sending NS for

2340:1111:AAAA:0:50A5:8A35:A5BB:66E1 on FastEthernet0/0*Mar 1 00:08:28.783: ICMPv6-ND: Received NA for

2340:1111:AAAA:0:50A5:8A35:A5BB:66E1 on FastEthernet0/0 from 2340:1111:AAAA:0:50A5:8A35:A5BB:66E1

*Mar 1 00:08:28.787: ICMPv6-ND: Neighbor 2340:1111:AAAA:0:50A5:8A35:A5BB:66E1 on FastEthernet0/0 : LLA 0021.9bd9.c644

IPv6-Router# un all

IPv6-Router# show ipv6 neighborsIPv6 Address Age Link-layer Addr State Interface2340:1111:AAAA:0:50A5:8A35:A5BB:66E1 0 0021.9bd9.c644 REACH Fa0/0FE80::50A5:8A35:A5BB:66E1 0 0021.9bd9.c644 REACH Fa0/02340:1111:AAAA:0:88C1:6A44:D6AF:1438 0 0021.9bd9.c644 REACH Fa0/0

• Used debug ipv6 nd

Replaces the IPv4 ARP table

Uses NDP Neighbor Solicitation and Neighbor Advertisement Messages

NS (Request for another node’s Link Layer Address) NA (Sent in response to NS)

Static Routes


Static Routes

Types of static routes (same as IPv4)

A directly attached static route is created using only the interface-type and interface-number parameters.

Router(config)# ipv6 route 2001:c00l::/32 serial 0/0/0

A recursive static route is created using only the next-hop address parameter.

Router(config)# ipv6 route 2001:c00l::/32 2001:12::1

A fully specified static route includes both the outgoing interface and the next hop address.

Router(config)# ipv6 route 2002:c00l::/32 fa 0/0 2001:12::1

A floating static route

Router(config)# ipv6 route 2001:c00l::/32 ser 0/0/0 15

Router(config)# ipv6 route ipv6-prefix/prefix-length {ipv6-address | interface-type interface-number [ipv6-address]} [administrative-distance] [administrative-multicast-distance | unicast | multicast] [next-hop-address] [tag tag]


Default Static Route

IPv6 default static route, which is equivalent to IPv4 ip route 0.0.0.0 0.0.0.0

Router(config)# ipv6 route ::/0 serial 0/0/0

Router(config)# ipv6 route ipv6-prefix/prefix-length {ipv6-address | interface-type interface-number [ipv6-address]} [administrative-distance] [administrative-multicast-distance | unicast | multicast] [next-hop-address] [tag tag]


Static Routes: Example

R1(config)# ipv6 route 2340:1111:AAAA:0102::/64 ser 0/0/0

R1# show ipv6 route<output omitted>S 2340:1111:AAAA:102::/64 [1/0] via ::, Serial0/0/0C 2340:1111:AAAA:A01::/64 [0/0] via ::, Serial0/0/0

R2(config)# ipv6 route 2340:1111:AAAA:0101::/64 2340:1111:AAAA:0A01::1

R2# show ipv6 route<output omitted>S 2340:1111:AAAA:101::/64 [1/0] via 2340:1111:AAAA:A01::1

R2# ping 2340:1111:AAAA:0101::1Sending 5, 100-byte ICMP Echos to 2340:1111:AAAA:101::1, timeout is 2 seconds:!!!!!Success rate is 100 percent (5/5), round-trip min/avg/max = 28/28/28 msR2#


Static Routes: Using Link-local address as the next-hop interface

R2(config)# no ipv6 route 2340:1111:AAAA:0101::/64 2340:1111:AAAA:0A01::1

R2(config)# ipv6 route 2340:1111:AAAA:0101::/64 fe80::1 % Interface has to be specified for a link-local nexthop

R2(config)# ipv6 route 2340:1111:AAAA:0101::/64 ser 0/0/0 fe80::1

R2# show ipv6 routeS 2340:1111:AAAA:101::/64 [1/0] via FE80::1, Serial0/0/0

R2# ping 2340:1111:AAAA:0101::1

Type escape sequence to abort.Sending 5, 100-byte ICMP Echos to 2340:1111:AAAA:101::1, timeout is 2 seconds:!!!!!Success rate is 100 percent (5/5), round-trip min/avg/max = 28/28/28 msR2#

Remember, due to the nature of link-local addresses, specific link-local networks do not appear in the routing table because they are considered to be available via all IPv6 interfaces.


Static Routes: clean-up…

Before we move on to dynamic routing remove all static routes

Verify that there are no static routes with show ipv6 route

R1(config)# no ipv6 route 2340:1111:AAAA:0102::/64 ser 0/0/0

R2(config)# no ipv6 route 2340:1111:AAAA:0101::/64 ser 0/0/0 fe80::1

EIGRP for IPv6


EIGRP vs EIGRP for IPv6EIGRP IPv4 IPv6

Advertises routes for… IPv4 IPv6

Layer 3 protocol for EIGRP messages

IPv4 IPv6

Layer 3 header protocol type 88 88

UDP Port N/A N/A

Uses Successor, Feasible Successor

yes yes

Uses Dual yes yes

Supports VLSM yes yes

Can perform automatic summarization

yes N/A

Uses triggered updates yes yes

Default metric bandwidth and delay

yes yes

Multicast Update destination 224.0.0.10 FF02::10

Authentication EIGRP-specific IPv6 AH/ESP


EIGRP for IPv6 Available in Cisco IOS Release 12.4(6)T and later

EIGRP for IPv4 and IPv6 are configured and managed separately although many of the commands are similar.

EIGRP for IPv6 is configured on a per-interface basis, no network command is used.

EIGRP for IPv6 has a shutdown feature which is the default state.

EIGRP for IPv6 does not do automatic summarization like EIGRP for IPv4.

EIGRP for IPv6 sees the neighbors link-local address as the next-hop IP address (neighbor table, topology table, routing table).

EIGRP for IPv6 does not require neighbors to be in the same IPv6 subnet to become neighbors.


EIGRP for IPv6 EIGRP Router ID decision steps based on IPv4 configuration:

1. Use the configured value (using the eigrp router-id a.b.c.d EIGRP subcommand under the ipv6 router eigrp command)

2. Use the highest IPv4 address on an up/up loopback interface

3. Use the highest IPv4 address on an up/up non-loopback interface

Note: In an IPv6 only environment the eigrp router-id command must be used otherwise the router will not form any EIGRP adjacencies.

IOS lets you stop and start the EIGRP process with the shutdown and no shutdown router mode subcommands.

After initial configuration, the EIGRP for IPv6 process starts in shutdown mode,

To start the EIGRP process it is required to issue the no shutdown


EIGRP for IPv6: All routers


Configuring R1

EIGRP for IPv6 is configured on the interfaces.

There are no network commands

R1(config)# inter fa 0/0R1(config-if)# ipv6 eigrp 100

R1(config)# inter ser 0/0/0R1(config-if)# ipv6 eigrp 100



Routing Table…

There are no EIGRP IPv6 routes in the routing table... yet.

R1# show ipv6 routeIPv6 Routing Table - 8 entries<output omitted> D - EIGRP, EX - EIGRP externalC 2340:1111:AAAA:101::/64 [0/0] via ::, FastEthernet0/0L 2340:1111:AAAA:101::1/128 [0/0] via ::, FastEthernet0/0C 2340:1111:AAAA:A01::/64 [0/0] via ::, Serial0/0/0L 2340:1111:AAAA:A01::1/128 [0/0] via ::, Serial0/0/0C 2340:1111:AAAA:A03::/64 [0/0] via ::, Serial0/0/1L 2340:1111:AAAA:A03::1/128 [0/0] via ::, Serial0/0/1L FE80::/10 [0/0] via ::, Null0L FF00::/8 [0/0] via ::, Null0


Show ipv6 protocols

There is an EIGRP 100 for IPv6 process but the interfaces are not yet enabled for EIGRP IPv6 because the process is shutdown.

R1# show ipv6 protocolsIPv6 Routing Protocol is "connected"IPv6 Routing Protocol is "static"IPv6 Routing Protocol is "eigrp 100" EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0 EIGRP maximum hopcount 100 EIGRP maximum metric variance 1 Interfaces: Redistribution: None Maximum path: 16 Distance: internal 90 external 170

R1# show ipv6 eigrp neighborsIPv6-EIGRP neighbors for process 100% EIGRP 100 is in SHUTDOWNR1#


Enabling EIGRP for IPv6

The EIGRP for IPv6 process must be enabled with the no shutdown command.




<The commands above were already completed>

R1(config)# ipv6 router eigrp 100R1(config-rtr)# router-id ? A.B.C.D EIGRP Router-ID in IP address format

R1(config-rtr)# router-id 1.1.1.1R1(config-rtr)# no shutdown


Verifying

The EIGRP for IPv6 process has been enabled but we don’t have any neighbors... yet.

R1# show ipv6 protocols IPv6 Routing Protocol is "connected"IPv6 Routing Protocol is "static"IPv6 Routing Protocol is "eigrp 100" EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0 EIGRP maximum hopcount 100 EIGRP maximum metric variance 1 Interfaces: FastEthernet0/0 Serial0/0/0 Serial0/0/1 Redistribution: None Maximum path: 16 Distance: internal 90 external 170

R1# show ipv6 eigrp neighborsIPv6-EIGRP neighbors for process 100


Configuring R2

Neighbor adjacencies begin for form...




R2(config)# ipv6 router eigrp 100R2(config-rtr)# router-id 2.2.2.2R2(config-rtr)# no shutdownR2(config-rtr)# endR2#*Jun 19 22:37:40.668: %DUAL-5-NBRCHANGE: IPv6-EIGRP(0) 100: Neighbor FE80::1

(Serial0/0/0) is up: new adjacency*Jun 19 22:37:41.248: %SYS-5-CONFIG_I: Configured from console by consoleR2#


Configuring R3R3(config)# inter fa 0/0R3(config-if)# ipv6 eigrp 100





R3(config)# ipv6 router eigrp 100R3(config-rtr)# router-id 3.3.3.3R3(config-rtr)# no shutdown


Configuring R4R4(config)# inter fa 0/0R4(config-if)# ipv6 eigrp 100



R4(config)# ipv6 router eigrp 100R4(config-rtr)# router-id 4.4.4.4R4(config-rtr)# no shutdown


Verifying

Notice that EIGRP for IPv6 uses link-local addresses to exchange EIGRP messages.

R1# show ipv6 eigrp neighborsIPv6-EIGRP neighbors for process 100H Address Interface Hold Uptime SRTT RTO Q Seq (sec) (ms) Cnt Num1 Link-local address: Se0/0/1 12 00:05:18 40 240 0 16 FE80::30 Link-local address: Se0/0/0 11 00:08:35 31 200 0 8 FE80::2R1#


EIGRP for IPv6 Topology Table

.

R1# show ipv6 eigrp topologyIPv6-EIGRP Topology Table for AS(100)/ID(1.1.1.1)Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply, r - reply Status, s - sia Status P 4444:0:0:4001::/64, 1 successors, FD is 2684416 via FE80::3 (2684416/2172416), Serial0/0/1P 2340:1111:AAAA:103::/64, 1 successors, FD is 2172416 via FE80::3 (2172416/28160), Serial0/0/1P 2340:1111:AAAA:A03::/64, 1 successors, FD is 2169856 via Connected, Serial0/0/1P 2340:1111:AAAA:B02::/64, 1 successors, FD is 2681856 via FE80::3 (2681856/2169856), Serial0/0/1P 2340:1111:AAAA:A02::/64, 1 successors, FD is 2681856 via FE80::2 (2681856/2169856), Serial0/0/0P 2340:1111:AAAA:102::/64, 1 successors, FD is 2172416 via FE80::2 (2172416/28160), Serial0/0/0P 2340:1111:AAAA:B01::/64, 1 successors, FD is 2681856 via FE80::3 (2681856/2169856), Serial0/0/1P 2340:1111:AAAA:A01::/64, 1 successors, FD is 2169856 via Connected, Serial0/0/0P 2340:1111:AAAA:101::/64, 1 successors, FD is 28160 via Connected, FastEthernet0/0R1#


IPv6 Routing Table

Link-local address is next-hop address

R1# show ipv6 routeIPv6 Routing Table - 14 entriesCodes: C - Connected, L - Local, S - Static, R - RIP, B - BGP <output omitted> D - EIGRP, EX - EIGRP externalC 2340:1111:AAAA:101::/64 [0/0] via ::, FastEthernet0/0L 2340:1111:AAAA:101::1/128 [0/0] via ::, FastEthernet0/0D 2340:1111:AAAA:102::/64 [90/2172416] via FE80::2, Serial0/0/0D 2340:1111:AAAA:103::/64 [90/2172416] via FE80::3, Serial0/0/1<output omitted>D 2340:1111:AAAA:B01::/64 [90/2681856] via FE80::3, Serial0/0/1D 2340:1111:AAAA:B02::/64 [90/2681856] via FE80::3, Serial0/0/1D 4444:0:0:4001::/64 [90/2684416] via FE80::3, Serial0/0/1


Verify

R1# ping 4444:0:0:4001::1

Type escape sequence to abort.Sending 5, 100-byte ICMP Echos to 4444:0:0:4001::1, timeout is 2 seconds:!!!!!Success rate is 100 percent (5/5), round-trip min/avg/max = 56/56/60 msR1#


R4 R3

R4# show ipv6 eigrp neighborsIPv6-EIGRP neighbors for process 100H Address Interface Hold Uptime SRTT RTO Q Seq (sec) (ms) Cnt Num1 Link-local address: Se0/0/1 12 00:04:33 61 366 0 19 FE80::30 Link-local address: Se0/0/0 13 00:04:33 1058 5000 0 18 FE80::3R4#


R4’s IPv6 Routing Table

All 2340:1111:AAAA networks are via R3

R4# show ipv6 routeD 2340:1111:AAAA:101::/64 [90/21026560] via FE80::3, Serial0/0/1 via FE80::3, Serial0/0/0D 2340:1111:AAAA:102::/64 [90/21026560] via FE80::3, Serial0/0/1 via FE80::3, Serial0/0/0D 2340:1111:AAAA:103::/64 [90/2172416] via FE80::3, Serial0/0/1 via FE80::3, Serial0/0/0D 2340:1111:AAAA:A01::/64 [90/21536000] via FE80::3, Serial0/0/1 via FE80::3, Serial0/0/0D 2340:1111:AAAA:A02::/64 [90/21024000] via FE80::3, Serial0/0/1 via FE80::3, Serial0/0/0D 2340:1111:AAAA:A03::/64 [90/21024000] via FE80::3, Serial0/0/1 via FE80::3, Serial0/0/0<output omitted>


Summary address..

R3(config)# inter ser 0/1/0R3(config-if)# ipv6 summary-address eigrp 100 2340:1111:AAAA::/48

R3(config)# inter ser 0/1/1R3(config-if)# ipv6 summary-address eigrp 100 2340:1111:AAAA::/48

R3# show ipv6 routeD 2340:1111:AAAA::/48 [5/28160] via ::, Null0<output omitted>

Summarize all 2340:1111:AAAA::/48 routes to R4

Null0 route added for summary route


R4# show ipv6 route

D 2340:1111:AAAA::/48 [90/2172416] via FE80::3, Serial0/0/0 via FE80::3, Serial0/0/1C 2340:1111:AAAA:B01::/64 [0/0] via ::, Serial0/0/0<output omitted>

R4# ping 2340:1111:AAAA:0101::1!!!!!

Reduced routing table for R4

Summary address..


EIGRP for IPv6: Default Route

DefaultStatic


Default Route (One method)

R3(config)# inter ser 0/0/0R3(config-if)# ipv6 summary-address eigrp 100 ::/0

R3(config)# inter ser 0/0/1R3(config-if)# ipv6 summary-address eigrp 100 ::/0

R3(config)# ipv6 route ::/0 ser 0/1/0R3(config)# ipv6 route ::/0 ser 0/1/1

R3# show ipv6 route

S ::/0 [1/0] via ::, Serial0/1/0 via ::, Serial0/1/1<output omitted>

Propagate an EIGRP ::/0 summary route to R1 and R2

Create the default static route

Verify static route

R4(config)# ipv6 route 2340:1111:AAAA::/48 ser 0/0/0 R4(config)# ipv6 route 2340:1111:AAAA::/48 ser 0/0/1

R4# show ipv6 route

S 2340:1111:AAAA::/48 [1/0] via ::, Serial0/0/0 via ::, Serial0/0/1


Verify Static RouteR1# show ipv6 route

D ::/0 [90/2172416] via FE80::3, Serial0/0/1C 2340:1111:AAAA:101::/64 [0/0] via ::, FastEthernet0/0L 2340:1111:AAAA:101::1/128 [0/0] via ::, FastEthernet0/0D 2340:1111:AAAA:102::/64 [90/2172416] via FE80::2, Serial0/0/0<output omitted>

R1# ping 4444::1

Type escape sequence to abort.Sending 5, 100-byte ICMP Echos to 4444::1, timeout is 2 seconds:!!!!!Success rate is 100 percent (5/5), round-trip min/avg/max = 56/56/56 msR1#

OSPFv3


OSPFv2 vs OSPFv3OSPF OSPFv2 (IPv4) OSPFv3

(IPv6)

Advertises routes for… IPv4 IPv6

Layer 3 protocol IPv4 IPv6

IP Protocol Type 89 89Source IP address IPv4 address IPv6 link-local

Multicast – all SPF routers 224.0.0.5 FF02::5

Multicast – All Designated routers 224.0.0.6 FF02::6

Uses Link State logic yes yes

Supports VLSM yes yesRID process, compared to OSPFv2 same same

LSA flooding and aging compared to OSPFv2

same same

Area structure compared to OSPFv2 same same

Packet types same same


OSPFv2 vs OSPFv3OSPF OSPFv2 (IPv4) OSPFv3

(IPv6)

LSA flooding and aging compared to OSPFv2

same same

RID yes yes

32-bit LSID yes yes Cost metric, bandwidth yes yes Supports route tags yes yes

DR/BDR election compared to OSPFv2 yes yes Periodic re-flooding every… 30 minutes 30 minutes

Authentication OSPF-specific IPv6 AH/ESP Neighbor checks compared to OSPFv2 same no "same

subnet" check

Multiple instances per interface no yes


OSPFv3 OSPFv3 is OSPF for IPv6 (RFC 2740):

Based on OSPFv2, with enhancements

Same mechanisms as IPv4, but a major rewrite of the internals of the protocol

Distributes IPv6 prefixes

Runs directly over IPv6

OSPFv3 & v2 can be run concurrently, because each address family has a separate SPF (ships in the night).

OSPFv3 uses the same basic packet types as OSPFv2:

Hello

Database description blocks (DDB)

Link state request (LSR)

Link state update (LSU)

Link state acknowledgement (ACK)

Neighbor discovery and adjacency formation mechanism are identical.

LSA flooding and aging mechanisms are identical.


OSPFv3 OSPFv3 Router ID decision steps based on OSPFv2 configuration:

1. Use the configured value (using the ospf router-id a.b.c.d OSPF subcommand under the ipv6 router ospf command)

2. Use the highest IPv4 address on an up/up loopback interface

3. Use the highest IPv4 address on an up/up non-loopback interface

Note: In an IPv6 only environment the ospf router-id command must be used otherwise the router will not form any OSPF adjacencies.

The multicast addresses used by OSPFv3 are as follows:

FF02::5— All SPF routers on the link-local scope; equivalent to 224.0.0.5 in OSPFv2.

FF02::6— All designated routers (DRs) on the link-local scope; equivalent to 224.0.0.6 in OSPFv2.


OSPFv3 (Single Area)

DefaultStatic

Removed all EIGRP for IPv6 commands and IPv6 default static routes


Configuring R1

Enable OSPF on the interface.

Create the OSPF process (do not need to do no shutdown)

R1(config)# inter fa 0/0R1(config-if)# ipv6 ospf 1 area 0

R1(config)# inter ser 0/0/0R1(config-if)# ipv6 ospf 1 area 0


R1(config)# ipv6 router ospf 1R1(config-rtr)# router-id 1.1.1.1


Configuring R2




R2(config)# ipv6 router ospf 1R2(config-rtr)# router-id 2.2.2.2


Configuring R3

Configure static default routes pointing to R4.

Propagate default into OSPF domain (use always option if there is not a static default configured).




R3(config)# ipv6 route ::/0 ser 0/1/0R3(config)# ipv6 route ::/0 ser 0/1/1

R3(config)# ipv6 router ospf 1R3(config-rtr)# router-id 3.3.3.3R3(config-rtr)# default-information originate


Configuring R4

Configure static routes on R4.

R4(config)# ipv6 route 2340:1111:AAAA::/48 ser 0/0/0 R4(config)# ipv6 route 2340:1111:AAAA::/48 ser 0/0/1

R4# show ipv6 route

S 2340:1111:AAAA::/48 [1/0] via ::, Serial0/0/0 via ::, Serial0/0/1


R3’s OSPFv3 and Static Routes

Static default route and OSPF routes.

R3# show ipv6 route

S ::/0 [1/0] via ::, Serial0/1/1 via ::, Serial0/1/0O 2340:1111:AAAA:101::/64 [110/782] via FE80::1, Serial0/0/0O 2340:1111:AAAA:102::/64 [110/782] via FE80::2, Serial0/0/1O 2340:1111:AAAA:A01::/64 [110/845] via FE80::2, Serial0/0/1 via FE80::1, Serial0/0/0<output omitted>


R1’s OSPFv3 Routes

OSPF routes including default.

R1# show ipv6 route ospf<output omitted> O - OSPF intra, OI - OSPF inter, OE1 - OSPF ext 1, OE2 - OSPF ext 2 ON1 - OSPF NSSA ext 1, ON2 - OSPF NSSA ext 2 D - EIGRP, EX - EIGRP externalOE2 ::/0 [110/1], tag 1 via FE80::3, Serial0/0/1O 2340:1111:AAAA:102::/64 [110/65] via FE80::2, Serial0/0/0O 2340:1111:AAAA:103::/64 [110/65] via FE80::3, Serial0/0/1O 2340:1111:AAAA:A02::/64 [110/128] via FE80::2, Serial0/0/0R1#R1# ping 4444::1!!!!!R1#


Show ipv6 ospf neighbor

Notice IPv4 Router-IDs.

R1# show ipv6 ospf neighbor

Neighbor ID Pri State Dead Time Interface ID Interface3.3.3.3 1 FULL/ - 00:00:38 6 Serial0/0/12.2.2.2 1 FULL/ - 00:00:37 6 Serial0/0/0R1#


Show ipv6 ospf

R1# show ipv6 ospf Routing Process "ospfv3 1" with ID 1.1.1.1 SPF schedule delay 5 secs, Hold time between two SPFs 10 secs Minimum LSA interval 5 secs. Minimum LSA arrival 1 secs LSA group pacing timer 240 secs Interface flood pacing timer 33 msecs Retransmission pacing timer 66 msecs Number of external LSA 1. Checksum Sum 0x007A8B Number of areas in this router is 1. 1 normal 0 stub 0 nssa Reference bandwidth unit is 100 mbps Area BACKBONE(0)

Number of interfaces in this area is 3SPF algorithm executed 8 timesNumber of LSA 11. Checksum Sum 0x06DDB0Number of DCbitless LSA 0Number of indication LSA 0Number of DoNotAge LSA 0Flood list length 0

Similar to OSPFv2


Show ipv6 ospf interface

Link local address of router is shown.

Used as source address for OSPFv3 packets.

R1# show ipv6 ospf inter ser 0/0/0Serial0/0/0 is up, line protocol is up Link Local Address FE80::1, Interface ID 6 Area 0, Process ID 1, Instance ID 0, Router ID 1.1.1.1 Network Type POINT_TO_POINT, Cost: 64 Transmit Delay is 1 sec, State POINT_TO_POINT, Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5 Hello due in 00:00:02 Index 1/2/2, flood queue length 0 Next 0x0(0)/0x0(0)/0x0(0) Last flood scan length is 2, maximum is 2 Last flood scan time is 0 msec, maximum is 0 msec Neighbor Count is 1, Adjacent neighbor count is 1 Adjacent with neighbor 2.2.2.2 Suppress hello for 0 neighbor(s)


Notes for CCNP Instructors/Students

IPv4 CEF and dCEF are enabled by default. IPv6 CEF and dCEF are disabled by default, but automatically enabled when you configure IPv6 routing.

To enable IPv6 CEF, use the ipv6 cef command

Router(config)# interface Fa0/0Router(config-if)# ipv6 ospf 1 area 51 stub

Router(config)# ipv6 router ospf 1Router(config-rtr)# area 0 range 2340:1111::/32

Router(config)# ipv6 router ospf 1Router(config-rtr)# summary-prefix 2001:1111::/32

Summarizes area 0’s routes to other areas as 2340:1111::/32 (ABR)

Stub and Totally Stubby (stub no-summary) areas configured on the stub interface

Summarizes external routes being redistributed into OSPF (ASBR)

Resources

Questions?


Documents

1 © 2011 Cisco Systems, Inc. All rights reserved. Cisco confidential.Cisco Networking Academy, US/Canada Introduction to Routing IPv6 Rick Graziani Computer