Как настроить маршрутизацию между двумя роутерами cisco

Enhanced Interior Gateway Routing Protocol (EIGRP), Intermediate System-to-Intermediate System (IS-IS), Open Shortest Path
First (OSPF), Routing Information Protocol (RIP) Version 2, and static routes support variable-length subnet masks (VLSMs).
With VLSMs, you can use different masks for the same network number on different interfaces, which allows you to conserve
IP addresses and more efficiently use available address space. However, using VLSMs also presents address assignment challenges
for the network administrator and ongoing administrative challenges.

Refer to RFC 1219 for detailed information about VLSMs and how to correctly assign addresses.

Note	Consider your decision to use VLSMs carefully. You can easily make mistakes in address assignments and you will generally find that the network is more difficult to monitor using VLSMs.

The best way to implement VLSMs is to keep your existing addressing plan in place and gradually migrate some networks to
VLSMs to recover address space.

Static routes are user-defined routes that cause packets moving between a source and a destination to take a specified path.
Static routes can be important if the device cannot build a route to a particular destination. They are also useful for specifying
a gateway of last resort to which all unroutable packets will be sent.

To configure a static route, use the
ip route
prefix mask {ip-address |
interface-type interface-number [ip-address]} [distance] [name] [permanent |
track
number] [tag
tag] global configuration command.

Static routes remains in the device configuration until you remove them (using the
no ip route global configuration command). However, you can override static routes with dynamic routing information through prudent assignment
of administrative distance values. An administrative distance is a rating of the trustworthiness of a routing information
source, such as an individual router or a group of routers. Numerically, an administrative distance is an integer from 0 to
255. In general, the higher the value, the lower the trust rating. An administrative distance of 255 means the routing information
source cannot be trusted at all and should be ignored.

Each dynamic routing protocol has a default administrative distance, as listed in the table below. If you want a static route
to be overridden by information from a dynamic routing protocol, simply ensure that the administrative distance of the static
route is higher than that of the dynamic protocol.

Static routes that point to an interface are advertised via RIP, EIGRP, and other dynamic routing protocols, regardless of
whether
redistribute static router configuration commands are specified for those routing protocols. These static routes are advertised because static
routes that point to an interface are considered in the routing table to be connected and hence lose their static nature.
However, if you define a static route to an interface that is not one of the networks defined in a
network command, no dynamic routing protocols will advertise the route unless a
redistribute static command is specified for these protocols.

When an interface goes down, all static routes through that interface are removed from the IP routing table. Also, when the
software can no longer find a valid next hop for the address specified as the address of the forwarding device in a static
route, the static route is removed from the IP routing table.

Default routes, also known as gateways of last resort, are used to route packets that are addressed to networks not explicitly
listed in the routing table. A device might not be able to determine routes to all networks. To provide complete routing capability,
network administrators use some devices as smart devices and give the remaining devices default routes to the smart device.
(Smart devices have routing table information for the entire internetwork.) Default routes can be either passed along dynamically
or configured manually into individual devices.

Most dynamic interior routing protocols include a mechanism for causing a smart device to generate dynamic default information,
which is then passed along to other devices.

You can use the
ip default-gateway global configuration command to define a default gateway when IP routing is disabled on a device. For instance, if a device
is a host, you can use this command to define a default gateway for the device. You can also use this command to transfer
a Cisco software image to a device when the device is in boot mode. In boot mode, IP routing is not enabled on the device.

Unlike the
ip default-gateway command, the
ip default-network command can be used when IP routing is enabled on a device. When you specify a network by using the
ip default-network command, the device considers routes to that network for installation as the gateway of last resort on the device.

Gateways of last resort configured by using the
ip default-network command are propagated differently depending on which routing protocol is propagating the default route. For Interior Gateway
Routing Protocol (IGRP) and Enhanced Interior Gateway Routing Protocol (EIGRP) to propagate the default route, the network
specified by the
ip default-network command must be known to IGRP or EIGRP. The network must be an IGRP- or EIGRP-derived network in the routing table, or the
static route used to generate the route to the network must be redistributed into IGRP or EIGRP or advertised into these protocols
by using the
network command. The Routing Information Protocol (RIP) advertises a route to network 0.0.0.0 if a gateway of last resort is configured
by using the
ip default-network command. The network specified in the
ip default-network command need not be explicitly advertised under RIP.

Creating a static route to network 0.0.0.0 0.0.0.0 by using the
ip route 0.0.0.0 0.0.0.0 command is another way to set the gateway of last resort on a device. As with the
ip default-network command, using the static route to 0.0.0.0 is not dependent on any routing protocols. However, IP routing must be enabled
on the device. IGRP does not recognize a route to network 0.0.0.0. Therefore, it cannot propagate default routes created by
using the
ip route 0.0.0.0 0.0.0.0 command. Use the
ip default-network command to have IGRP propagate a default route.

EIGRP propagates a route to network 0.0.0.0, but the static route must be redistributed into the routing protocol.

Depending on your release of the Cisco software, the default route created by using the
ip route 0.0.0.0 0.0.0.0 command is automatically advertised by RIP devices. In some releases, RIP does not advertise the default route if the route
is not learned via RIP. You might have to redistribute the route into RIP by using the
redistribute command.

Default routes created using the
ip route 0.0.0.0 0.0.0.0 command are not propagated by Open Shortest Path First (OSPF) and Intermediate System to Intermediate System (IS-IS). Additionally,
these default routes cannot be redistributed into OSPF or IS-IS by using the
redistribute command. Use the
default-information originate command to generate a default route into an OSPF or IS-IS routing domain.

By default, most IP routing protocols install a maximum of four parallel routes in a routing table. Static routes always
install six routes. The exception is Border Gateway Protocol (BGP), which by default allows only one path (the best path)
to a destination. However, BGP can be configured to use equal and unequal cost multipath load sharing.

The number of parallel routes that you can configure to be installed in the routing table is dependent on the installed version
of Cisco software. To change the maximum number of parallel paths allowed, use the

maximum-paths
number-paths command in router configuration mode.

Multi-interface load splitting allows you to efficiently control traffic that travels across multiple interfaces to the same
destination. The
traffic-share min router configuration command specifies that if multiple paths are available to the same destination, only paths with the
minimum metric will be installed in the routing table. The number of paths allowed is never more than six. For dynamic routing
protocols, the number of paths is controlled by the
maximum-paths router configuration command. The static route source can install six paths. If more paths are available, the extra paths
are discarded. If some installed paths are removed from the routing table, pending routes are added automatically.

In addition to running multiple routing protocols simultaneously, Cisco software can be configured to redistribute information
from one routing protocol to another. For example, you can configure a device to readvertise Enhanced Interior Gateway Routing
Protocol (EIGRP)-derived routes using the Routing Information Protocol (RIP), or to readvertise static routes using the EIGRP
protocol. Redistribution from one routing protocol to another can be configured in all of the IP-based routing protocols.

You also can conditionally control the redistribution of routes between routing domains by configuring route maps between
the two domains. A route map is a route/packet filter that is configured with permit and deny statements, match and set clauses,
and sequence numbers.

Although redistribution is a protocol-independent feature, some of the
match and
set commands are specific to a particular protocol.

One or more
match commands and one or more
set commands are configured in route map configuration mode. If there are no
match commands, then everything matches. If there are no
set commands, then no set action is performed.

To define a route map for redistribution, use the
route-map
map-tag [permit |
deny] [sequence-number] global configuration command.

The metrics of one routing protocol do not necessarily translate into the metrics of another. For example, the RIP metric
is a hop count and the EIGRP metric is a combination of five metric values. In such situations, a dynamic metric is assigned
to the redistributed route. Redistribution in these cases should be applied consistently and carefully with inbound filtering
to avoid routing loops.

Removing options that you have configured for the
redistribute command requires careful use of the
no redistribute command to ensure that you obtain the result that you are expecting.

Filtering sources of routing information prioritizes routing information from different sources because some pieces of routing
information might be more accurate than others. An administrative distance is a rating of the trustworthiness of a routing
information source, such as an individual device or a group of devices. In a large network, some routing protocols and some
devices can be more reliable than others as sources of routing information. Also, when multiple routing processes are running
in the same device for IP, the same route could be advertised by more than one routing process. By specifying administrative
distance values, you enable the device to intelligently discriminate between sources of routing information. The device always
picks the route whose routing protocol has the lowest administrative distance.

There are no general guidelines for assigning administrative distances because each network has its own requirements. You
must determine a reasonable matrix of administrative distances for the network as a whole.

For example, consider a device using the Enhanced Interior Gateway Routing Protocol (EIGRP) and the Routing Information Protocol
(RIP). Suppose you trust the EIGRP-derived routing information more than the RIP-derived routing information. In this example,
because the default EIGRP administrative distance is lower than the default RIP administrative distance, the device uses the
EIGRP-derived information and ignores the RIP-derived information. However, if you lose the source of the EIGRP-derived information
(because of a power shutdown at the source network, for example), the device uses the RIP-derived information until the EIGRP-derived
information reappears.

Note

You can also use administrative distance to rate the routing information from devices that are running the same routing protocol. This application is generally discouraged if you are unfamiliar with this particular use of administrative distance because it can result in inconsistent routing information, including forwarding loops.

Note	The weight of a route can no longer be set with the distance command. To set the weight for a route, use a route map.

Key management is a method of controlling the authentication keys used by routing protocols. Not all protocols support key
management. Authentication keys are available for Director Response Protocol (DRP) Agent, Enhanced Interior Gateway Routing
Protocol (EIGRP), and Routing Information Protocol (RIP) Version 2.

You can manage authentication keys by defining key chains, identifying the keys that belong to the key chain, and specifying
how long each key is valid. Each key has its own key identifier (specified using the
key chain configuration command), which is stored locally. The combination of the key identifier and the interface associated with
the message uniquely identifies the authentication algorithm and the message digest algorithm 5 (MD5) authentication key in
use.

You can configure multiple keys with lifetimes. Only one authentication packet is sent, regardless of how many valid keys
exist. The software examines the key numbers in ascending order and uses the first valid key it encounters. The lifetimes
allow for overlap during key changes.

You can redistribute routes from one routing domain into another, with or without controlling the redistribution with a route
map. To control which routes are redistributed, configure a route map and reference the route map from the
redistribute command.

The tasks in this section describe how to define the conditions for redistributing routes (a route map), how to redistribute
routes, and how to remove options for redistributing routes, depending on the protocol being used.

SUMMARY STEPS

1. 
   enable

2. 
   configure
   terminal

3. key chain
   name-of-chain

4. key
   number
5. key-string
   text

6. accept-lifetime
   start-time {infinite |
   end-time |
   duration
   seconds}

7. send-lifetime
   start-time {infinite |
   end-time |
   duration
   seconds}

8. end
9. show key chain

DETAILED STEPS

Device> enable

Device# configure terminal

Device(config)# key chain chain1

Device(config-keychain)# key 1

Device(config-keychain-key)# key-string string1

Device(config-keychain-key)# accept-lifetime 13:30:00 Dec 22 2011 duration 7200

Device(config-keychain-key)# send-lifetime 14:30:00 Dec 22 2011 duration 3600

Device(config-keychain-key)# end

Device# show key chain

The following example uses two different subnet masks for the class B network address of 172.16.0.0. A subnet mask of /24
is used for LAN interfaces. The /24 mask allows 265 subnets with 254 host IP addresses on each subnet. The final subnet of
the range of possible subnets using a /24 mask (172.16.255.0) is reserved for use on point-to-point interfaces and assigned
a longer mask of /30. The use of a /30 mask on 172.16.255.0 creates 64 subnets (172.16.255.0 to 172.16.255.252) with 2 host
addresses on each subnet.

Caution: To ensure unambiguous routing, you must not assign 172.16.255.0/24 to a LAN interface in your network.

Device(config)# interface GigabitEthernet 0/0/0
Device(config-if)# ip address 172.16.1.1 255.255.255.0
Device(config-if)# ! 8 bits of host address space reserved for GigabitEthernet interfaces 
Device(config-if)# exit
Device(config)# interface Serial 0/0/0
Device(config-if)# ip address 172.16.255.5 255.255.255.252
Device(config-if)# ! 2 bits of address space reserved for point-to-point serial interfaces
Device(config-if)# exit
Device(config)# router rip 
Device(config-router)# network 172.16.0.0
Device(config-router)# ! Specifies the network directly connected to the device 

In the following example, packets for network 10.0.0.0 from Device B (where the static route is installed) will be routed
through 172.18.3.4 if a route with an administrative distance less than 110 is not available. The figure below illustrates
this example. The route learned by a protocol with an administrative distance of less than 110 might cause Device B to send
traffic destined for network 10.0.0.0 via the alternate path through Device D.

Device(config)# ip route 10.0.0.0 255.0.0.0 172.18.3.4 110

The following example shows how to configure IP address 172.16.5.4 as the default route when IP routing is disabled:

Device> enable
Device# configure terminal
Device(conf)# no ip routing
Device(conf)# ip default-gateway 172.16.15.4

In the following example, the
router eigrp global configuration command configures Enhanced Interior Gateway Routing Protocol (EIGRP) routing in autonomous system 1.
The
network command configuration specifies EIGRP routing on networks 192.168.7.0 and 172.16.0.0. The first
distance router configuration command sets the default administrative distance to 255, which instructs the device to ignore all routing
updates from devices for which an explicit distance has not been set. The second
distance command sets the administrative distance to 80 for internal EIGRP routes and to 100 for external EIGRP routes. The third

distance command sets the administrative distance to 120 for the device with the address 172.16.1.3.

Device(config)# router eigrp 1 
Device(config-router)# network 192.168.7.0 
Device(config-router)# network 172.16.0.0 
Device(config-router)# distance 255 
Device(config-router)# distance eigrp 80 100 
Device(config-router)# distance 120 172.16.1.3 0.0.0.0 

Note	The distance eigrp command must be used to set the administrative distance for EIGRP-derived routes.

The following example assigns the device with the address 192.168.7.18 an administrative distance of 100 and all other devices
on subnet 192.168.7.0 an administrative distance of 200:

Device(config-router)# distance 100 192.168.7.18 0.0.0.0 
Device(config-router)# distance 200 192.168.7.0 0.0.0.255 

However, if you reverse the order of these two commands, all devices on subnet 192.168.7.0 are assigned an administrative
distance of 200, including the device at address 192.168.7.18:

Device(config-router)# distance 200 192.168.7.0 0.0.0.255 
Device(config-router)# distance 100 192.168.7.18 0.0.0.0 

Note	Assigning administrative distances can be used to solve unique problems. However, administrative distances should be applied carefully and consistently to avoid the creation of routing loops or other network failures.

In the following example, the distance value for IP routes learned is 90. Preference is given to these IP routes rather than
routes with the default administrative distance value of 110.

Device(config)# router isis 
Device(config-router)# distance 90 ip 

In the example that follows, three static routes are specified, two of which are to be advertised. The static routes are
created by specifying the
redistribute static router configuration command and then specifying an access list that allows only those two networks to be passed to the Enhanced
Interior Gateway Routing Protocol (EIGRP) process. Any redistributed static routes should be sourced by a single device to
minimize the likelihood of creating a routing loop.

Device(config)# ip route 192.168.2.0 255.255.255.0 192.168.7.65 
Device(config)# ip route 192.168.5.0 255.255.255.0 192.168.7.65 
Device(config)# ip route 10.10.10.0 255.255.255.0 10.20.1.2 
Device(config)# ! 
Device(config)# access-list 3 permit 192.168.2.0 0.0.255.255 
Device(config)# access-list 3 permit 192.168.5.0 0.0.255.255 
Device(config)# access-list 3 permit 10.10.10.0 0.0.0.255 
Device(config)# ! 
Device(config)# router eigrp 1 
Device(config-router)# network 192.168.0.0 
Device(config-router)# network 10.10.10.0 
Device(config-router)# redistribute static metric 10000 100 255 1 1500
Device(config-router)# distribute-list 3 out static

Each Enhanced Interior Gateway Routing Protocol (EIGRP) routing process provides routing information to only one autonomous
system. The Cisco software must run a separate EIGRP process and maintain a separate routing database for each autonomous
system that it services. However, you can transfer routing information between these routing databases.

In the following configuration, network 10.0.0.0 is configured under EIGRP autonomous system 1 and network 192.168.7.0 is
configured under EIGRP autonomous system 101:

Device(config)# router eigrp 1 
Device(config-router)# network 10.0.0.0 
Device(config-router)# exit 
Device(config)# router eigrp 101 
Device(config-router)# network 192.168.7.0 

In the following example, routes from the 192.168.7.0 network are redistributed into autonomous system 1 (without passing
any other routing information from autonomous system 101):

Device(config)# access-list 3 permit 192.168.7.0 
Device(config)# ! 
Device(config)# route-map 101-to-1 permit 10 
Device(config-route-map)# match ip address 3 
Device(config-route-map)# set metric 10000 100 1 255 1500 
Device(config-route-map)# exit 
Device(config)# router eigrp 1 
Device(config-router)# redistribute eigrp 101 route-map 101-to-1 
Device(config-router)#! 

The following example is an alternative way to redistribute routes from the 192.168.7.0 network into autonomous system 1.
Unlike the previous configuration, this method does not allow you to set the metric for redistributed routes.

Device(config)# access-list 3 permit 192.168.7.0 
Device(config)# ! 
Device(config)# router eigrp 1 
Device(config-router)# redistribute eigrp 101 
Device(config-router)# distribute-list 3 out eigrp 101 
Device(config-router)# !

Consider a WAN at a university that uses the Routing Information Protocol (RIP) as an interior routing protocol. Assume that
the university wants to connect its WAN to regional network 172.16.0.0, which uses the Enhanced Interior Gateway Routing Protocol
(EIGRP) as the routing protocol. The goal in this case is to advertise the networks in the university network to devices in
the regional network.

Mutual redistribution is configured between EIGRP and RIP in the following example:

Device(config)# access-list 10 permit 172.16.0.0 
Device(config)# ! 
Device(config)# router eigrp 1 
Device(config-router)# network 172.16.0.0 
Device(config-router)# redistribute rip metric 10000 100 255 1 1500 
Device(config-router)# default-metric 10
Device(config-router)# distribute-list 10 out rip 
Device(config-router)# exit
Device(config)# router rip 
Device(config-router)# redistribute eigrp 1 
Device(config-router)# ! 

In this example, an EIGRP routing process is started. The
network router configuration command specifies that network 172.16.0.0 (the regional network) is to send and receive EIGRP routing
information. The
redistribute router configuration command specifies that RIP-derived routing information be advertised in routing updates. The
default-metric router configuration command assigns an EIGRP metric to all RIP-derived routes. The
distribute-list router configuration command instructs the Cisco software to use access list 10 (not defined in this example) to limit the
entries in each outgoing update. The access list prevents unauthorized advertising of university routes to the regional network.

In the following example, mutual redistribution is configured between the Enhanced Interior Gateway Routing Protocol (EIGRP)
and the Border Gateway Protocol (BGP).

Routes from EIGRP routing process 101 are injected into BGP autonomous system 50000. A filter is configured to ensure that
the correct routes are advertised, in this case, three networks. Routes from BGP autonomous system 50000 are injected into
EIGRP routing process 101. The same filter is used.

Device(config)# ! All networks that should be advertised from R1 are controlled with ACLs: 
Device(config)# access-list 1 permit 172.18.0.0 0.0.255.255 
Device(config)# access-list 1 permit 172.16.0.0 0.0.255.255 
Device(config)# access-list 1 permit 172.25.0.0 0.0.255.255
Device(config)# ! Configuration for router R1:
Device(config)# router bgp 50000 
Device(config-router)# network 172.18.0.0 
Device(config-router)# network 172.16.0.0 
Device(config-router)# neighbor 192.168.10.1 remote-as 2 
Device(config-router)# neighbor 192.168.10.15 remote-as 1 
Device(config-router)# neighbor 192.168.10.24 remote-as 3 
Device(config-router)# redistribute eigrp 101 
Device(config-router)# distribute-list 1 out eigrp 101 
Device(config-router)# exit 
Device(config)# router eigrp 101 
Device(config-router)# network 172.25.0.0
Device(config-router)# redistribute bgp 50000 
Device(config-router)# distribute-list 1 out bgp 50000 
Device(config-router)# ! 

Caution

BGP should be redistributed into an Interior Gateway Protocol (IGP) when there are no other suitable options. Redistribution from BGP into any IGP should be applied with proper filtering by using distribute lists, IP prefix lists, and route map statements to limit the number of prefixes.

OSPF typically requires coordination among many internal devices, area border routers (ABRs), and Autonomous System Boundary
Routers (ASBRs). At a minimum, OSPF-based devices can be configured with all default parameter values, with no authentication,
and with interfaces assigned to areas.

This section provides the following configuration examples:

• The first example shows simple configurations illustrating basic OSPF commands.

• The second example shows configurations for an internal device, ABR, and ASBR within a single, arbitrarily assigned OSPF
  autonomous system.

• The third example illustrates a more complex configuration and the application of various tools available for controlling
  OSPF-based routing environments.

The following example shows a device in autonomous system 1 that is configured to run both the Routing Information Protocol
(RIP) and the Enhanced Interior Gateway Routing Protocol (EIGRP). The example advertises EIGRP-derived routes using RIP and
assigns the EIGRP-derived routes a RIP metric of 10.

Device(config)# router rip 
Device(config-router)# redistribute eigrp 1 
Device(config-router)# default-metric 10 
Device(config-router)# exit 

The examples in this section illustrate the use of redistribution, with and without route maps. Examples from both the IP
and Connectionless Network Service (CLNS) routing protocols are given. The following example redistributes all Open Shortest
Path First (OSPF) routes into the Enhanced Interior Gateway Routing Protocol (EIGRP):

Device(config)# router eigrp 1 
Device(config-router)# redistribute ospf 101 
Device(config-router)# exit 

The following example redistributes Routing Information Protocol (RIP) routes with a hop count equal to 1 into OSPF. These
routes will be redistributed into OSPF as external link state advertisements (LSAs) with a metric of 5, metric a type of type
1, and a tag equal to 1.

Device(config)# router ospf 1 
Device(config-router)# redistribute rip route-map rip-to-ospf 
Device(config-router)# exit 
Device(config)# route-map rip-to-ospf permit 
Device(config-route-map)# match metric 1 
Device(config-route-map)# set metric 5 
Device(config-route-map)# set metric-type type 1 
Device(config-route-map)# set tag 1 
Device(config-route-map)# exit 

The following example redistributes OSPF learned routes with tag 7 as a RIP metric of 15:

Device(config)# router rip 
Device(config-router)# redistribute ospf 1 route-map 5 
Device(config-router)# exit 
Device(config)# route-map 5 permit 
Device(config-route-map)# match tag 7 
Device(config-route-map)# set metric 15 

The following example redistributes OSPF intra-area and interarea routes with next hop devices on serial interface 0/0/0
into the Border Gateway Protocol (BGP) with an INTER_AS metric of 5:

Device(config)# router bgp 50000 
Device(config-router)# redistribute ospf 1 route-map 10 
Device(config-router)# exit 
Device(config)# route-map 10 permit 
Device(config-route-map)# match route-type internal 
Device(config-route-map)# match interface serial 0/0/0 
Device(config-route-map)# set metric 5 

The following example redistributes two types of routes into the integrated IS-IS routing table (supporting both IP and CLNS).
The first type is OSPF external IP routes with tag 5; these routes are inserted into Level 2 IS-IS link-state packets (LSPs)
with a metric of 5. The second type is ISO-IGRP derived CLNS prefix routes that match CLNS access list 2000; these routes
will be redistributed into IS-IS as Level 2 LSPs with a metric of 30.

Device(config)# router isis 
Device(config-router)# redistribute ospf 1 route-map 2 
Device(config-router)# redistribute iso-igrp nsfnet route-map 3 

Device(config-router)# exit 
Device(config)# route-map 2 permit 
Device(config-route-map)# match route-type external 
Device(config-route-map)# match tag 5 
Device(config-route-map)# set metric 5 
Device(config-route-map)# set level level-2 
Device(config-route-map)# exit 
Device(config)# route-map 3 permit 
Device(config-route-map)# match address 2000 
Device(config-route-map)# set metric 30 
Device(config-route-map)# exit 

With the following configuration, OSPF external routes with tags 1, 2, 3, and 5 are redistributed into RIP with metrics of
1, 1, 5, and 5, respectively. The OSPF routes with a tag of 4 are not redistributed.

Device(config)# router rip 
Device(config-router)# redistribute ospf 101 route-map 1 
Device(config-router)# exit 
Device(config)# route-map 1 permit 
Device(config-route-map)# match tag 1 2 
Device(config-route-map)# set metric 1 
Device(config-route-map)# exit 
Device(config)# route-map 1 permit 
Device(config-route-map)# match tag 3 
Device(config-route-map)# set metric 5 
Device(config-route-map)# exit 
Device(config)# route-map 1 deny 
Device(config-route-map)# match tag 4 
Device(config-route-map)# exit 
Device(config)# route map 1 permit 
Device(config-route-map)# match tag 5 
Device(config-route-map)# set metric 5 
Device(config-route-map)# exit 

Given the following configuration, a RIP learned route for network 172.18.0.0 and an ISO-IGRP learned route with prefix 49.0001.0002
will be redistributed into an IS-IS Level 2 LSP with a metric of 5:

Device(config)# router isis 
Device(config-router)# redistribute rip route-map 1 
Device(config-router)# redistribute iso-igrp remote route-map 1 
Device(config-router)# exit 
Device(config)# route-map 1 permit 
Device(config-route-map)# match ip address 1 
Device(config-route-map)# match clns address 2 
Device(config-route-map)# set metric 5 
Device(config-route-map)# set level level-2 
Device(config-route-map)# exit 
Device(config)# access-list 1 permit 172.18.0.0 0.0.255.255 
Device(config)# clns filter-set 2 permit 49.0001.0002... 

The following configuration example illustrates how a route map is referenced by the
default-information router configuration command. This type of reference is called conditional default origination. OSPF will originate the default
route (network 0.0.0.0) with a type 2 metric of 5 if 172.20.0.0 is in the routing table.

Device(config)# route-map ospf-default permit 
Device(config-route-map)# match ip address 1 
Device(config-route-map)# set metric 5 
Device(config-route-map)# set metric-type type-2 
Device(config-route-map)# exit 
Device(config)# access-list 1 172.20.0.0 0.0.255.255 
Device(config)# router ospf 101 
Device(config-router)# default-information originate route-map ospf-default 

The following example configures a key chain named chain1. In this example, the software always accepts and sends key1 as
a valid key. The key key2 is accepted from 1:30 p.m. to 3:30 p.m. and is sent from 2:00 p.m. to 3:00 p.m. The overlap allows
for migration of keys or discrepancy in the set time of the device. Likewise, the key key3 immediately follows key2, and there
is 30-minutes on each side to handle time-of-day differences.

Device(config)# interface GigabitEthernet 0/0/0
Device(config-if)# ip rip authentication key-chain chain1 
Device(config-if)# ip rip authentication mode md5 
Device(config-if)# exit 
Device(config)# router rip
Device(config-router)# network 172.19.0.0 
Device(config-router)# version 2 
Device(config-router)# exit 
Device(config)# key chain chain1 
Device(config-keychain)# key 1 
Device(config-keychain-key)# key-string key1 
Device(config-keychain-key)# exit
Device(config-keychain)# key 2 
Device(config-keychain-key)# key-string key2 
Device(config-keychain-key)# accept-lifetime 13:30:00 Jan 25 2005 duration 7200 
Device(config-keychain-key)# send-lifetime 14:00:00 Jan 25 2005 duration 3600  
Device(config-keychain-key)# exit
Device(config-keychain)# key 3 
Device(config-keychain-key)# key-string key3 
Device(config-keychain-key)# accept-lifetime 14:30:00 Jan 25 2005 duration 7200 
Device(config-keychain-key)# send-lifetime 15:00:00 Jan 25 2005 duration 3600 
Device(config-keychain-key)# end 

The following example configures a key chain named chain1:

Device(config)# key chain chain1 
Device(config-keychain)# key 1 
Device(config-keychain-key)# key-string key1 
Device(config-keychain-key)# exit
Device(config-keychain)# key 2 
Device(config-keychain-key)# key-string key2 
Device(config-keychain-key)# accept-lifetime 00:00:00 Dec 5 2004 23:59:59 Dec 5 2005 
Device(config-keychain-key)# send-lifetime 06:00:00 Dec 5 2004 18:00:00 Dec 5 2005 
Device(config-keychain-key)# exit 
Device(config-keychain)# exit 
Device(config)# interface GigabitEthernet 0/0/0 
Device(config-if)# ip address 172.19.104.75 255.255.255.0 secondary 172.19.232.147 255.255.255.240 
Device(config-if)# ip rip authentication key-chain chain1 
Device(config-if)# media-type 10BaseT 
Device(config-if)# exit 
Device(config)# interface GigabitEthernet 1/0/0
Device(config-if)# no ip address 
Device(config-if)# shutdown 
Device(config-if)# media-type 10BaseT 
Device(config-if)# exit 
Device(config)# interface Fddi 0 
Device(config-if)# ip address 10.1.1.1 255.255.255.0 
Device(config-if)# no keepalive 
Device(config-if)# exit 
Device(config)# interface Fddi 1/0/0
Device(config-if)# ip address 172.16.1.1 255.255.255.0 
Device(config-if)# ip rip send version 1 
Device(config-if)# ip rip receive version 1 
Device(config-if)# no keepalive 
Device(config-if)# exit 
Device(config)# router rip 
Device(config-router)# version 2 
Device(config-router)# network 172.19.0.0 
Device(config-router)# network 10.0.0.0 
Device(config-router)# network 172.16.0.0