Configuring Backup Data Lines and Remote Management

The Cisco 819 series and Cisco 880 Series Integrated Services Routers (ISRs) support backup data connectivity with a backup data line that enables them to mitigate WAN downtime.


Note


Voice backup is available on router models C881SRST and C888SRST. For information on configuring voice backup, see Configuring Voice Functionality

Cisco 880 ISRs also support remote management functions as follows:

  • Through the auxiliary port on Cisco 880 series ISRs
  • Through the ISDN S/T port on the Cisco 880 series ISRs

Cisco 819 ISRs a support remote management functions through the auxiliary port on any Cisco 819 series ISRs.


Note


On Cisco 819 sries and Cisco880 series ISRs, the console port and the auxiliary port are on the same physical RJ-45 port; therefore, the two ports cannot be activated simultaneously. You must use the CLI to enable the desired function.

Note


Cisco 892F ISRs have a Gigabit Ethernet (GE) port that supports copper connections or a small-form-factor pluggable (SFP) port that supports fiber connections and can be configured for failover redundancy when the network goes down.

This chapter describes configuring backup data lines and remote management in the following sections:

Configuring Backup Interfaces

When the router receives an indication that the primary interface is down, the backup interface becomes enabled. After the primary connection has been restored for a specified period, the backup interface is disabled.

Even if the backup interface comes out of standby mode, the router does not enable the backup interface unless the router receives the traffic specified for that backup interface.

Table below shows the backup interfaces for Cisco 810, Cisco 880 and Cisco 890 series ISRs, along with their port designations. Basic configurations for these interfaces are given in the Configuring WAN Interfaces

Table 1 Model Numbers and Data Line Backup Capabilities

Router Model Number

ISDN

3G

V.92

881G, 886G, 887G, 887VG, 888G

Yes

886, 886VA, 887, 887V, 888, 888E

Yes

891

Yes

892, 892F

Yes

819

Yes

To configure your router with a backup interface, perform these steps, beginning in global configuration mode:

SUMMARY STEPS

    1.    interface type number

    2.    backup interface interface-type interface-number

    3.    exit


DETAILED STEPS
     Command or ActionPurpose
    Step 1interface type number


    Example:
    Router(config)# interface atm 0
     

    Enters interface configuration mode for the interface for which you want to configure the backup.

    This interface can be a serial, ISDN, or asynchronous.

    The example shows the configuration of a backup interface for an ATM WAN connection.

     
    Step 2backup interface interface-type interface-number


    Example:
    Router(config-if)# backup interface bri 0
     

    Assigns an interface as the secondary, or backup interface.

    This can be a serial interface or asynchronous interface. For example, a serial 1 interface could be configured to back up a serial 0 interface.

    The example shows a BRI interface configured as the backup interface for the ATM 0 interface.

     
    Step 3exit


    Example:
    Router(config-if)# exit
    Router(config)#
     

    Exits the configuration interface mode.

     

    Configuring Cellular Dial-on-Demand Routing Backup

    To monitor the primary connection and initiate the backup connection over the cellular interface when needed, the router can use one of the following methods:

    • Backup Interface—Backup interface that stays in standby mode until the primary interface line protocol is detected as down and then is brought up. See the Configuring Backup Interfaces.
    • Dialer Watch—Backup feature that integrates dial backup with routing capabilities. See the Configuring DDR Backup Using Dialer Watch.
    • Floating Static Route—Route through the backup interface has an administrative distance that is greater than the administrative distance of the primary connection route and therefore would not be in the routing table until the primary interface goes down. When the primary interaface goes down, the floating static route is used. See the Configuring DDR Backup Using Floating Static Route.

    Note


    You cannot configure a backup interface for the cellular interface and any other asynchronous serial interface.

    Configuring DDR Backup Using Dialer Watch

    To initiate dialer watch, you must configure the interface to perform dial-on-demand routing (DDR) and backup. Use traditional DDR configuration commands, such as dialer maps, for DDR capabilities. To enable dialer watch on the backup interface and create a dialer list, use the following commands in interface configuration mode.

    or

    dialer group dialer group number

    SUMMARY STEPS

      1.    configure terminal

      2.    interface type number

      3.    dialer watch-group group-number

      4.    dialer watch-list group-number ip ip-address address-mask

      5.    dialer-list dialer-group protocol protocol-name {permit | deny | list access-list-number | access-group}

      6.    ip access-list access-list-number permit ip source address

      7.    interface cellular 0

      8.    Do one of the following:

      • dialer string string
      • or
      • dialer group dialer group number


    DETAILED STEPS
       Command or ActionPurpose
      Step 1configure terminal


      Example:
      Router# configure terminal
       

      Enters global configuration mode.

       
      Step 2interface type number


      Example:
      Router (config)# interface ATM0
       

      Specifies the interface.

       
      Step 3dialer watch-group group-number


      Example:
      Router(config-if)# dialer watch-group 2
       

      Enables dialer watch on the backup interface.

       
      Step 4dialer watch-list group-number ip ip-address address-mask


      Example:
      Router(config-if)# dialer watch-list 2 ip 10.4.0.254 255.255.0.0
       

      Defines a list of all IP addresses to be watched.

       
      Step 5dialer-list dialer-group protocol protocol-name {permit | deny | list access-list-number | access-group}


      Example:
      Router(config)# dialer-list 2 protocol ip permit
       

      Creates a dialer list for traffic of interest and permits access to an entire protocol.

       
      Step 6ip access-list access-list-number permit ip source address


      Example:
      Router(config)# access list 2 permit 10.4.0.0
       

      Defines traffic of interest.

      Do not use the access list permit all command to avoid sending traffic to the IP network. This may result in call termination.

       
      Step 7interface cellular 0


      Example:
      Router (config)# interface cellular 0
       

      Specifies the cellular interface.

       
      Step 8Do one of the following:
      • dialer string string
      • or
      • dialer group dialer group number


      Example:
      Router (config-if)# dialer string cdma  *** cdma ***

      or

      Router (config-if)# dialer group 2      *** gsm ***
       

      CDMA only. Specifies the dialer script (defined using the chat script command).

      GSM only. Maps a dialer list to the dialer interface.

       

      Configuring DDR Backup Using Floating Static Route

      To configure a floating static default route on the secondary interface, use the following commands, beginning in the global configuration mode.


      Note


      Make sure you have ip classless enabled on your router.
      SUMMARY STEPS

        1.    configure terminal

        2.    ip route network-number network-mask {ip address | interface} [administrative distance] [name name]


      DETAILED STEPS
         Command or ActionPurpose
        Step 1configure terminal


        Example:
        Router# configure terminal
         

        Enters global configuration mode from the terminal.

         
        Step 2ip route network-number network-mask {ip address | interface} [administrative distance] [name name]


        Example:
        Router (config)# ip route 0.0.0.0 Dialer 2 track 234
         

        Establishes a floating static route with the configured administrative distance through the specified interface.

        A higher administrative distance should be configured for the route through the backup interface, so that the backup interface is used only when the primary interface is down.

         

        Cellular Wireless Modem as Backup with NAT and IPsec Configuration

        The following example shows how to configure the 3G wireless modem as backup with NAT and IPsec on either GSM or CDMA networks.


        Note


        The receive and transmit speeds cannot be configured. The actual throughput depends on the cellular network service.
        Current configuration : 3433 bytes
        !
        version 12.4
        no service pad
        service timestamps debug datetime msec
        service timestamps log datetime msec
        no service password-encryption
        !
        hostname Router
        !
        boot-start-marker
        boot-end-marker
        !
        !
        no aaa new-model
        !
        !
        ! 
        !
        crypto isakmp policy 1
         encr 3des
         authentication pre-share
        crypto isakmp key gsm address 128.107.241.234              *** or cdma ***
        !
        !
        crypto ipsec transform-set gsm ah-sha-hmac esp-3des        *** or cdma ***
        !
        crypto map gsm1 10 ipsec-isakmp                            *** or cdma1 ***
         set peer 128.107.241.234
         set transform-set gsm                                     *** or cdma ***
         match address 103
        !
        !
        !
        no ip dhcp use vrf connected
        ip dhcp excluded-address 10.4.0.254
        !
        ip dhcp pool gsmpool                                        *** or cdmapool ***
           network 10.4.0.0 255.255.0.0
           dns-server 66.209.10.201 66.102.163.231 
           default-router 10.4.0.254 
        !
        !
        ip cef
        !
        no ipv6 cef
        multilink bundle-name authenticated
        chat-script gsm "" "atdt*98*1#" TIMEOUT 30 "CONNECT"        *** or cdma ***
        !
        !
        archive
         log config
          hidekeys
        !
        !
        controller DSL 0
         mode atm
         line-term cpe
         line-mode 4-wire standard
         line-rate 4608
        !
        !
        !
        !
        interface ATM0
         no ip address
         ip virtual-reassembly
         load-interval 30
         no atm ilmi-keepalive
        !
        interface ATM0.1 point-to-point
         backup interface Cellular0
         ip nat outside
         ip virtual-reassembly
         pvc 0/35 
          pppoe-client dial-pool-number 2
         !
        !
        interface FastEthernet0
        !
        interface FastEthernet1
        !
        interface FastEthernet2
        !
        interface FastEthernet3
        !
        interface Cellular0
         ip address negotiated
         ip nat outside
         ip virtual-reassembly
         encapsulation ppp
         no ip mroute-cache
         dialer in-band
         dialer idle-timeout 0
         dialer string gsm                                      *** or cdma ***
         dialer-group 1
         async mode interactive
         no ppp lcp fast-start
         ppp chap hostname chunahayev@wwan.ccs
         ppp chap password 0 B7uhestacr
         ppp ipcp dns request
         crypto map gsm1                                       *** or cdma1 ***
        !
        interface Vlan1
         description used as default gateway address for DHCP clients
         ip address 10.4.0.254 255.255.0.0
         ip nat inside
         ip virtual-reassembly
        !
        interface Dialer2
         ip address negotiated
         ip mtu 1492
         ip nat outside
         ip virtual-reassembly
         encapsulation ppp
         load-interval 30
         dialer pool 2
         dialer-group 2
         ppp authentication chap callin
         ppp chap hostname cisco@dsl.com
         ppp chap password 0 cisco
         ppp ipcp dns request
         crypto map gsm1                                       *** or cdma1 ***
        !
        ip local policy route-map track-primary-if
        ip forward-protocol nd
        ip route 0.0.0.0 0.0.0.0 Dialer2 track 234
        ip route 0.0.0.0 0.0.0.0 Cellular0 254
        no ip http server
        no ip http secure-server
        !
        !
        ip nat inside source route-map nat2cell interface Cellular0 overload
        ip nat inside source route-map nat2dsl interface Dialer2 overload
        !         
        ip sla 1
         icmp-echo 209.131.36.158 source-interface Dialer2
         timeout 1000
         frequency 2
        ip sla schedule 1 life forever start-time now
        access-list 1 permit any
        access-list 2 permit 10.4.0.0 0.0.255.255
        access-list 3 permit any
        access-list 101 permit ip 10.4.0.0 0.0.255.255 any
        access-list 102 permit icmp any host 209.131.36.158
        access-list 103 permit ip host 166.136.225.89 128.107.0.0 0.0.255.255
        access-list 103 permit ip host 75.40.113.246 128.107.0.0 0.0.255.255
        dialer-list 1 protocol ip list 1
        dialer-list 2 protocol ip permit
        !
        !
        !
        route-map track-primary-if permit 10
         match ip address 102
         set interface Dialer2
        !
        route-map nat2dsl permit 10
         match ip address 101
         match interface Dialer2
        !
        route-map nat2cell permit 10
         match ip address 101
         match interface Cellular0
        !
        !
        control-plane
        !
        !
        line con 0
         no modem enable
        line aux 0
        line 3
         exec-timeout 0 0
         script dialer gsm                                    *** or cdma ***
         login
         modem InOut
         no exec
        line vty 0 4
         login
        !
        scheduler max-task-time 5000
         
        !
        webvpn cef
        end

        Configuring Dial Backup and Remote Management Through the Console or Auxiliary Port

        When customer premises equipment, such as a Cisco 880 series ISR or Cisco 819 series ISR, is connected to an ISP, an IP address is dynamically assigned to the router, or the IP address may be assigned by the router peer through the centrally managed function. The dial backup feature can be added to provide a failover route in case the primary line fails. The Cisco 880 series ISRs can use the auxiliary port for dial backup and remote management.

        Figure below shows the network configuration used for remote management access and for providing backup to the primary WAN line.

        Figure 1. Dial Backup and Remote Management Through the Auxiliary Port

        1

        Cisco 880 series router

        A

        Main WAN link; primary connection to Internet service provider

        2

        Modem

        B

        Dial backup; serves as a failover link for Cisco 880 routers when the primary line goes down

        3

        PC

        C

        Remote management; serves as dial-in access to allow changes or updates to Cisco IOS configurations

        To configure dial backup and remote management for these routers, perform these steps, beginning in global configuration mode:

        SUMMARY STEPS

          1.    ip name-server server-address

          2.    ip dhcp pool name

          3.    exit

          4.    chat-script script-name expect-send

          5.    interface type number

          6.    exit

          7.    interface type number

          8.    dialer watch-group group-number

          9.    exit

          10.    ip nat inside source {list access-list-number} {interface type number | pool name} [overload]

          11.    ip route prefix mask {ip-address | interface-type interface-number [ip-address]

          12.    access-list access-list-number {deny | permit} source [source-wildcard]

          13.    dialerwatch-list group-number {ipip-address address-mask | delay route-check initial seconds

          14.    line [aux | console | tty | vty] line-number [ending-line-number]

          15.    modem enable

          16.    exit

          17.    line [aux | console | tty | vty] line-number [ending-line-number]

          18.    flowcontrol {none | software [lock] [in | out] | hardware [in | out]}


        DETAILED STEPS
           Command or ActionPurpose
          Step 1ip name-server server-address


          Example:
          Router(config)# ip name-server 192.168.28.12
           

          Enters your ISP DNS IP address.

          Tip   

          You may add multiple server addresses if available.

           
          Step 2ip dhcp pool name


          Example:
          Router(config)# ip dhcp pool 1
           

          Creates a DHCP address pool on the router and enters DHCP pool configuration mode. The name argument can be a string or an integer.

          Configure the DHCP address pool. For sample commands that you can use in DHCP pool configuration mode, see the Example for specifying an IP address for the ATM interface through PPP and IPCP address negotiation and dial backup.

           
          Step 3exit


          Example:
          Router(config-dhcp)#exit
           

          Exits config-dhcp mode and enters global configuration mode.

           
          Step 4chat-script script-name expect-send


          Example:
          Router(config)# 
          chat-script Dialout ABORT ERROR ABORT BUSY ““ “AT” OK “ATDT 5555102 T” TIMEOUT 45 CONNECT \c
          
           

          Configures a chat script used in dial-on-demand routing (DDR) to give commands for dialing a modem and for logging in to remote systems. The defined script is used to place a call over a modem connected to the PSTN.

           
          Step 5interface type number


          Example:
          Router(config)# 
          interface Async 1
          
           

          Creates and enters configuration mode for the asynchronous interface.

          Configure the asynchronous interface. For sample commands that you can use in asynchronous interface configuration mode, see the Example for specifying an IP address for the ATM interface through PPP and IPCP address negotiation and dial backup.

           
          Step 6exit


          Example:
          Router(config-if)# exit
           

          Enters global configuration mode.

           
          Step 7interface type number


          Example:
          Router(config)# 
          interface Dialer 3
          
           

          Creates and enters configuration mode for the dilaer interface.

           
          Step 8dialer watch-group group-number


          Example:
          Router(config-if)# dialer watch-group 1
           

          Specifies the group number for the watch list.

           
          Step 9exit


          Example:
          Router(config-if)# 
          exit
          
           

          Exits the interface configuration mode.

           
          Step 10ip nat inside source {list access-list-number} {interface type number | pool name} [overload]


          Example:
          Router(config)# 
          ip nat inside source list 101 interface Dialer 3 overload
          
           

          Enables dynamic translation of addresses on the inside interface.

           
          Step 11ip route prefix mask {ip-address | interface-type interface-number [ip-address]


          Example:
          Router(config)# ip route 0.0.0.0 0.0.0.0 22.0.0.2
           

          Sets the IP route to point to the dialer interface as a default gateway.

           
          Step 12access-list access-list-number {deny | permit} source [source-wildcard]


          Example:
          Router(config)# access-list 1 permit 192.168.0.0 0.0.255.255 any
           

          Defines an extended access list that indicates which addresses need translation.

           
          Step 13dialerwatch-list group-number {ipip-address address-mask | delay route-check initial seconds


          Example:
          Router(config)# dialer watch-list 1 ip 22.0.0.2 255.255.255.255
           

          Evaluates the status of the primary link, based on the existence of routes to the peer. The address 22.0.0.2 is the peer IP address of the ISP.

           
          Step 14line [aux | console | tty | vty] line-number [ending-line-number]

          Example:
          Router(config)# line console 0
           

          Enters configuration mode for the line interface.

           
          Step 15modem enable


          Example:
          Router(config-line)# modem enable
           

          Switches the port from console to auxiliary port function.

           
          Step 16exit


          Example:
          Router(config-line)# exit
           

          Exits the configure interface mode.

           
          Step 17line [aux | console | tty | vty] line-number [ending-line-number]

          Example:
          Router(config)# line aux 0
           

          Enters configuration mode for the auxiliary interface.

           
          Step 18flowcontrol {none | software [lock] [in | out] | hardware [in | out]}

          Example:
          Router(config)# flowcontrol hardware
           

          Enables hardware signal flow control.

           

          Example for specifying an IP address for the ATM interface through PPP and IPCP address negotiation and dial backup

          The following configuration example specifies an IP address for the ATM interface through PPP and IPCP address negotiation and dial backup over the console port.

          !
          ip name-server 192.168.28.12
          ip dhcp excluded-address 192.168.1.1
          !
          ip dhcp pool 1
           import all
           network 192.168.1.0 255.255.255.0
           default-router 192.168.1.1
          !
          ! Need to use your own correct ISP phone number.
          modemcap entry MY-USER_MODEM:MSC=&F1S0=1
          chat-script Dialout ABORT ERROR ABORT BUSY ““ “AT” OK “ATDT 5555102\T”
          TIMEOUT 45 CONNECT \c
          !
          !
          !
          !
          interface vlan 1
           ip address 192.168.1.1 255.255.255.0
           ip nat inside
           ip tcp adjust-mss 1452
           hold-queue 100 out
          !
          ! Dial backup and remote management physical interface.
          interface Async1
           no ip address
           encapsulation ppp
           dialer in-band
           dialer pool-member 3
           async default routing
           async dynamic routing
           async mode dedicated
           ppp authentication pap callin
          !
          interface ATM0
           mtu 1492
           no ip address
           no atm ilmi-keepalive
           pvc 0/35
           pppoe-client dial-pool-number 1
          !
          dsl operating-mode auto
          !
          ! Primary WAN link.
          interface Dialer1
           ip address negotiated
           ip nat outside
           encapsulation ppp
           dialer pool 1
           ppp authentication pap callin
           ppp pap sent-username account password 7 pass
           ppp ipcp dns request
           ppp ipcp wins request
           ppp ipcp mask request
          !
          ! Dialer backup logical interface.
          interface Dialer3
           ip address negotiated
           ip nat outside
           encapsulation ppp
           no ip route-cache
           no ip mroute-cache
           dialer pool 3
           dialer idle-timeout 60
           dialer string 5555102 modem-script Dialout
           dialer watch-group 1
          !
          ! Remote management PC IP address.
          peer default ip address 192.168.2.2
          no cdp enable
          !
          ! Need to use your own ISP account and password.
          ppp pap sent-username account password 7 pass
          ppp ipcp dns request
          ppp ipcp wins request
          ppp ipcp mask request
          !
          ! IP NAT over Dialer interface using route-map.
          ip nat inside source route-map main interface Dialer1 overload
          ip nat inside source route-map secondary interface Dialer3 overload
          ip classless
          !
          ! When primary link is up again, distance 50 will override 80 if dial backup 
          ! has not timed out. Use multiple routes because peer IP addresses are alternated 
          ! among them when the CPE is connected.
          ip route 0.0.0.0 0.0.0.0 64.161.31.254 50
          ip route 0.0.0.0 0.0.0.0 66.125.91.254 50
          ip route 0.0.0.0 0.0.0.0 64.174.91.254 50
          ip route 0.0.0.0 0.0.0.0 63.203.35.136 80
          ip route 0.0.0.0 0.0.0.0 63.203.35.137 80
          ip route 0.0.0.0 0.0.0.0 63.203.35.138 80
          ip route 0.0.0.0 0.0.0.0 63.203.35.139 80
          ip route 0.0.0.0 0.0.0.0 63.203.35.140 80
          ip route 0.0.0.0 0.0.0.0 63.203.35.141 80
          ip route 0.0.0.0 0.0.0.0 Dialer1 150
          no ip http server
          ip pim bidir-enable
          !
          ! PC IP address behind CPE.
          access-list 101 permit ip 192.168.0.0 0.0.255.255 any
          access-list 103 permit ip 192.168.0.0 0.0.255.255 any
          !
          ! Watch multiple IP addresses because peers are alternated 
          ! among them when the CPE is connected.
          dialer watch-list 1 ip 64.161.31.254 255.255.255.255
          dialer watch-list 1 ip 64.174.91.254 255.255.255.255
          dialer watch-list 1 ip 64.125.91.254 255.255.255.255
          !
          ! Dial backup will kick in if primary link is not available 
          ! 5 minutes after CPE starts up.
          dialer watch-list 1 delay route-check initial 300
          dialer-list 1 protocol ip permit
          !
          ! Direct traffic to an interface only if the dialer is assigned an IP address.
          route-map main permit 10
           match ip address 101
           match interface Dialer1
          !
          route-map secondary permit 10
           match ip address 103
           match interface Dialer3
          !
          ! Change console to aux function.
          line con 0
           exec-timedout 0 0
           modem enable
           stopbits 1
          line aux 0
           exec-timeout 0 0
           ! To enable and communicate with the external modem properly.
           script dialer Dialout
           modem InOut
           modem autoconfigure discovery
           transport input all 
           stopbits 1
           speed 115200
           flowcontrol hardware
          line vty 0 4
           exec-timeout 0 0
           password cisco
           login
          !
          scheduler max-task-time 5000
          end
          

          Configuring Data Line Backup and Remote Management Through the ISDN S/T Port

          Cisco 880 series routers can use the ISDN S/T port for remote management. Figure 1 and Figure 2 show two typical network configurations that provide remote management access and backup for the primary WAN line. In Figure 1, the dial backup link goes through a customer premises equipment (CPE) splitter, a digital subscriber line access multiplexer (DSLAM), and a central office (CO) splitter before connecting to the ISDN switch. In Figure 2, the dial backup link goes directly from the router to the ISDN switch.

          Figure 2. Data Line Backup Through CPE Splitter, DSLAM, and CO Splitter

          1

          Cisco 880 series router

          A

          Primary DSL interface, FE interface (Cisco 881 router)

          2

          DSLAM

          B

          Dial backup and remote management through the ISDN interface (ISDN S/T port); serves as a failover link when the primary line goes down

          3

          ATM aggregator

          4

          ISDN switch

          5

          ISDN

          C

          Provides administrator with remote management capability through the ISDN interface when the primary DSL link is down; serves as dial-in access to allow changes or updates to Cisco IOS configuration

          6

          ISDN peer router

          7

          Web server

          8

          Administrator

          Figure 3. Data Line Backup Directly from Router to ISDN Switch

          1

          PC

          A

          Primary DSL interface

          2

          Cisco 880 series ISR

          B

          Dial backup and remote management through the ISDN interface (ISDN S/T port); serves as a failover link when the primary line goes down

          3

          DSLAM

          4

          Aggregator

          5

          ISDN switch

          C

          Provides administrator with remote management capability through the ISDN interface when the primary DSL link is down; serves as dial-in access to allow changes or updates to Cisco IOS configuration

          6

          Web server

          7

          Administrator

          To configure dial backup and remote management through the ISDN S/T port of your router, perform the following procedures:

          Configuring ISDN Settings


          Note


          Traffic of interest must be present to activate the backup ISDN line by means of the backup interface and floating static routes methods. Traffic of interest is not needed for the dialer watch to activate the backup ISDN line.

          To configure your router ISDN interface for use as a backup interface, perform these steps, beginning in global configuration mode:

          SUMMARY STEPS

            1.    isdn switch-type switch-type

            2.    interface type number

            3.    encapsulation encapsulation-type

            4.    dialer pool-member number

            5.    isdn switch-type switch-type

            6.    exit

            7.    interface dialer dialer-rotary-group-number

            8.    ip address negotiated

            9.    encapsulation encapsulation-type

            10.    dialer pool number

            11.    dialer string dial-string#[:isdn-subaddress]

            12.    dialer-group group-number

            13.    exit

            14.    dialer-list dialer-group protocol protocol-name {permit | deny | list access-list-number | access-group}


          DETAILED STEPS
             Command or ActionPurpose
            Step 1isdn switch-type switch-type


            Example:
            Router(config)# isdn switch-type basic-net3
             

            Specifies the ISDN switch type.

            The example specifies a switch type used in Australia, Europe, and the United Kingdom. For details on other supported switch types, see the Cisco IOS Dial Technologies Command Reference .

             
            Step 2interface type number


            Example:
            Router(config)# interface bri 0
             

            Enters configuration mode for the ISDN BRI.

             
            Step 3encapsulation encapsulation-type


            Example:
            Router(config-if)# encapsulation ppp
             

            Sets the BRI0 interface encapsulation type.

             
            Step 4dialer pool-member number


            Example:
            Router(config-if)# dialer pool-member 1
             

            Specifies the dialer pool membership.

             
            Step 5isdn switch-type switch-type


            Example:
            Router(config-if)# isdn switch-type basic-net3
             

            Specifies the ISDN switch type.

             
            Step 6exit


            Example:
            Router(config-if)# exit
             

            Exits configuration interface mode and enters global configuration mode.

             
            Step 7interface dialer dialer-rotary-group-number


            Example:
            Router(config)# interface dialer 0
             

            Creates a dialer interface (numbered 0 to 255) and enters interface configuration mode.

             
            Step 8ip address negotiated


            Example:
            Router(config-if)# ip address negotiated
             

            Specifies that the IP address for the interface is obtained through PPP/IPCP (IP Control Protocol) address negotiation. The IP address is obtained from the peer.

             
            Step 9encapsulation encapsulation-type


            Example:
            Router(config-if)# encapsulation ppp
             

            Sets the encapsulation type to PPP for the interface.

             
            Step 10dialer pool number


            Example:
            Router(config-if)# dialer pool 1
             

            Specifies the dialer pool to be used.

            In the example, the dialer pool 1 setting associates the dialer 0 interface with the BRI0 interface because the BRI0 dialer pool-member value is 1.

             
            Step 11dialer string dial-string#[:isdn-subaddress]


            Example:
            Router(config-if)# dialer string 384040
             

            Specifies the telephone number to be dialed.

             
            Step 12dialer-group group-number


            Example:
            Router(config-if)# dialer group 1
             

            Assigns the dialer interface to a dialer group (1–10).

             
            Step 13exit


            Example:
            Router(config-if)# exit
             

            Exits dialer 0 interface configuration mode, and enters global configuration mode.

             
            Step 14dialer-list dialer-group protocol protocol-name {permit | deny | list access-list-number | access-group}


            Example:
            Router(config)# dialer-list 1 protocol ip permit
             

            Creates a dialer list for packets of interest to be forwarded through the specified interface dialer group.

            In the example, dialer-list 1 corresponds to dialer-group 1.

            For details about this command and additional parameters that can be set, see Cisco IOS Dial Technologies Command Reference .

             

            Configuring Aggregator and ISDN Peer Router

            The ISDN peer router is any router that has an ISDN interface and can communicate through a public ISDN network to reach your Cisco router ISDN interface. The ISDN peer router provides Internet access for your Cisco router during the ATM network downtime.

            The aggregator is typically a concentrator router where your Cisco router ATM PVC terminates. In the following configuration example, the aggregator is configured as a PPPoE server.

            ! This portion of the example configures the aggregator.
            vpdn enable
            no vpdn logging
            !
            vpdn-group 1
             accept-dialin
             protocol pppoe
             virtual-template 1
            !
            interface Ethernet3
             description “4700ref-1”
             ip address 40.1.1.1 255.255.255.0
             media-type 10BaseT
            !
            interface Ethernet4
             ip address 30.1.1.1 255.255.255.0
             media-type 10BaseT
            !
            interface Virtual-Template1
             ip address 22.0.0.2 255.255.255.0
             ip mtu 1492
             peer default ip address pool adsl
            !
            interface ATM0
             no ip address
             pvc 1/40
             encapsulation aal5snap
             protocol pppoe
            !
            no atm limi-keepalive
            !
            ip local pool adsl 22.0.0.1
            ip classless
            ip route 0.0.0.0 0.0.0.0 22.0.0.1 50
            ip route 0.0.0.0 0.0.0.0 30.1.1.2.80
            ! This portion of the example configures the ISDN peer.
            isdn switch-type basic-net3
            !
            interface Ethernet0
             ip address 30.1.1.2 255.0.0.0 
            !
            interface BRI0
             description “to 836-dialbackup”
             no ip address
             encapsulation ppp
             dialer pool-member 1
             isdn switch-type basic-net3
            !
            interface Dialer0
             ip address 192.168.2.2 255.255.255.0
             encapsulation ppp
             dialer pool 1
             dialer string 384020
             dialer-group 1
             peer default ip address pool isdn
            !
            ip local pool isdn 192.168.2.1
            ip http server
            ip classless
            ip route 0.0.0.0 0.0.0.0 192.168.2.1
            ip route 40.0.0.0 255.0.0.0 30.1.1.1
            !
            dialer-list 1 protocol ip permit!

            Configuring Gigabit Ethernet Failover Media

            Cisco 892F routers have a Gigabit Ethernet (GE) port that supports copper connections or a small-form-factor pluggable (SFP) port that supports fiber connections. Media can be configured for failover redundancy when the network goes down.

            To assign primary and secondary failover media on the GE-SFP port, perform these steps, beginning in global configuration mode.

            SUMMARY STEPS

              1.    hostname name

              2.    enable secret password

              3.    interface gigabitethernet slot/port

              4.    media-type {sfp | rj45} auto-failover

              5.    exit


            DETAILED STEPS
               Command or ActionPurpose
              Step 1hostname name


              Example:
              Router(config)# hostname Router
               

              Specifies the name for the router.

               
              Step 2enable secret password


              Example:
              Router(config)# enable secret cr1ny5ho
               

              Specifies an encrypted password to prevent unauthorized access to the router.

               
              Step 3interface gigabitethernet slot/port


              Example:
              Router(config)# interface gigabitethernet 0/1
               

              Enters interface configuration mode.

               
              Step 4media-type {sfp | rj45} auto-failover


              Example:
              Router(config-if)# media-type sfp auto-failover

              Or

              Router(config-if)# media-type rj45 auto-failover
               

              Configures the port with SFP as the primary media for automatic failover from SFP to RJ-45.

              Or

              Configures the port with RJ-45 as the primary media for automatic failover from RJ-45 to SFP.

               
              Step 5exit


              Example:
              Router(config-if)# exit

              Or

              Router(config)#
               

              Exits interface configuration mode and returns to global configuration mode.

               

              Configuring Auto-Detect

              The Auto-Detect feature is enabled if media-type is not configured. This feature automatically detects which media is connected and links up. If both media are connected, whichever media comes up first is linked up.


              Note


              The Auto-Detect feature only works with 1000 Base SFPs. This feature does not detect 100 Base SFPs.

              To configure the Auto-Detect feature, perform the following steps, starting in global configuration mode:

              SUMMARY STEPS

                1.    interface gigabitethernet slot/port

                2.    no media-type

                3.    exit


              DETAILED STEPS
                 Command or ActionPurpose
                Step 1interface gigabitethernet slot/port


                Example:
                Router(config)# interface gigabitethernet 0/1
                 

                Enters interface configuration mode.

                 
                Step 2no media-type


                Example:
                Router(config-if)# no media-type
                GigabitEthernet0/1: Changing media to UNKNOWN.

                You may need to update the speed and duplex settings for this interface.

                 

                Enables Auto-Detect. If a 1000Base SFP is plugged in, the speed and duplex are set automatically to 1000 and full. Speed and duplex options are not available. An RJ45 connection will only work with speed as 1000 and duplex as full. If an SFP is not plugged in, all speeds and duplexes are available for the RJ45 media.

                Note    The Auto-Detect feature only works with 1000Base SFPs. This feature does not detect 100Base SFPs.
                 
                Step 3exit


                Example:
                Router(config-if)# exit
                Router(config)#
                 

                Exits interface configuration mode and returns to global configuration mode.

                 

                Configuring Third-Party SFPs

                Small Form-Factor Pluggables (SFPs) that are not Cisco certified are called third-party SFPs. Cisco approved means the SFPs have undergone rigorous testing with Cisco products and the SFPs are guaranteed to have 100% compatibility.

                Third-party SFPs are manufactured by companies that are not on the Cisco-approved Vendor List (AVL). Currently, Cisco ISR G2 routers support only Cisco-approved SFPs. From Release 15.3(2)T, Cisco ISR G2 routers recognize third-party SFPs.


                Note


                Cisco does not provide any kind of support for the third-party SFPs because they are not validated by Cisco.

                Note


                • Supports only 100BASE SFPs and 1000BASE SFPs under two speed configurations:
                • 100 Mbps speed for 100BASE SFPs
                • 1000 Mbps speed for 1000BASE SFPs
                • Only the following routers and modules support third-party SFPs:
                • Cisco 2921 Integrated Services Router
                • Cisco 2951 Integrated Services Router
                • Cisco 3900 Integrated Services Router
                • Cisco 3900E Series Integrated Services Routers
                • Cisco 892-F Gigabit Ethernet Security Router
                • Cisco 898-EA Gigabit Ethernet Security Router
                • EHWIC-1GE-SFP


                SUMMARY STEPS

                  1.    enable

                  2.    configure terminal

                  3.    service unsupported-transceiver

                  4.    interface type slot/subslot/port number

                  5.    media-type sfp

                  6.    speed value

                  7.    shutdown

                  8.    no shutdown

                  9.    exit


                DETAILED STEPS
                   Command or ActionPurpose
                  Step 1enable


                  Example:
                  Router> enable
                   

                  Enables the privileged EXEC mode.

                  Enter your password if prompted.

                   
                  Step 2configure terminal


                  Example:
                  Router# configure terminal
                   

                  Enters the global configuration mode.

                   
                  Step 3service unsupported-transceiver


                  Example:
                  Router(config)# service unsupported-transceiver
                   

                  Enables third-party SFP support.

                   
                  Step 4interface type slot/subslot/port number


                  Example:
                  Router(config)# interface ethernet 0/3/0
                   

                  Selects an interface to configure.

                   
                  Step 5media-type sfp


                  Example:
                  Router(config-if)# media-type sfp
                   

                  Changes media type to SFP.

                   
                  Step 6speed value


                  Example:
                  Router(config-if)# speed 100
                   

                  Configures the speed of the interface.

                  Note    For 100BASE SFPs, configure the speed to 100 Mbps only. Similarly, for 1000BASE SFPs, configure the speed to 1000 Mbps only.
                   
                  Step 7shutdown


                  Example:
                  Router(config-if)# shutdown
                   

                  Disables the interface, changing its state from administratively UP to administratively DOWN.

                   
                  Step 8no shutdown


                  Example:
                  Router(config-if)# no shutdown
                   

                  Enables the interface, changing its state from administratively DOWN to administratively UP.

                   
                  Step 9exit


                  Example:
                  Router(config-if)# exit
                  Router(config)# 
                   

                  Exits the configuration mode and returns the global configuration mode.

                   

                  Example for Configuring Third-Party SFPs

                  This example shows how to configure a third-party SFP on a Cisco ISR G2 Series Router:

                  Router# configure terminal 
                  Router(config-if)# service unsupported-transceiver
                  Router(config)# interface ethernet 0/3/0
                  Router(config-if)# media-type sfp
                  Router(config-if)# speed 100
                  Router(config-if)# shutdown 
                  Router(config-if)# no shutdown
                  Router(config-if)# exit
                  Router(config)# exit