IP Unnumbered Ethernet Polling Support

The IP Unnumbered Ethernet Polling Support feature provides IP unnumbered support for Ethernet physical interfaces. This support already exists for serial interfaces.

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Information About IP Unnumbered Ethernet Polling Support

IP Unnumbered Ethernet Polling Support Overview

IP unnumbered support for serial interfaces is extended to Ethernet physical interfaces. Unnumbered Ethernet physical interfaces are used in the same manner as unnumbered serial interfaces. On a device, if a loopback interface is configured and an IP address is assigned to it, using the polling option more than one Ethernet physical interface can be unnumbered to the loopback.

The polling option enables the dynamic discovery of hosts (connected though the unnumbered interfaces) based on the Address Resolution Protocol (ARP) protocol.

How to Configure IP Unnumbered Ethernet Polling Support

Enabling Polling on an Ethernet Interface

SUMMARY STEPS

    1.    enable

    2.    configure terminal

    3.    interface type number

    4.    ip address ip-address mask

    5.    exit

    6.    interface type number

    7.    ip unnumbered type number poll

    8.    end


DETAILED STEPS
     Command or ActionPurpose
    Step 1 enable


    Example:
    Device> enable
     

    Enables privileged EXEC mode.

    • Enter your password if prompted.

     
    Step 2 configure terminal


    Example:
    Device# configure terminal
     

    Enters global configuration mode.

     
    Step 3 interface type number


    Example:
    Device(config)# interface loopback 0
     

    Specifies an interface and enters interface configuration mode.

     
    Step 4 ip address ip-address mask


    Example:
    Device(config-if)# ip address 209.165.200.229 255.255.240.224
     

    Configures the IP address on the interface.

     
    Step 5 exit


    Example:
    Device(config-if)# exit
     

    Exits interface configuration mode and returns to global configuration mode.

     
    Step 6 interface type number


    Example:
    Device(config)# interface ethernet 0/0
     

    Specifies an interface and enters interface configuration mode.

     
    Step 7 ip unnumbered type number poll


    Example:
    Device(config-if)# ip unnumbered loopback 0 poll
     

    Enables IP–connected host polling on the specified interface.

     
    Step 8 end


    Example:
    Device(config-if)# end
     

    Returns to privileged EXEC mode.

     

    Configuring the Queue Size and the Packet Rate for IP ARP Polling for Unnumbered Interfaces

    SUMMARY STEPS

      1.    enable

      2.    configure terminal

      3.    ip arp poll queue queue-size

      4.    ip arp poll rate packet-rate

      5.    end


    DETAILED STEPS
       Command or ActionPurpose
      Step 1 enable


      Example:
      Device> enable
       

      Enables privileged EXEC mode.

      • Enter your password if prompted.

       
      Step 2 configure terminal


      Example:
      Device# configure terminal
       

      Enters global configuration mode.

       
      Step 3 ip arp poll queue queue-size


      Example:
      Device(config)# ip arp poll queue 1000
       

      Configures the IP ARP polling queue size.

       
      Step 4 ip arp poll rate packet-rate


      Example:
      Device(config)# ip arp poll rate 1000
       

      Configures the IP ARP polling packet rate, in packets per second.

       
      Step 5 end


      Example:
      Device(config-if)# end
       

      Returns to privileged EXEC mode.

       

      Verifying IP Unnumbered Ethernet Polling Support

      Perform this task to verify IP unnumbered Ethernet polling support.


      Note

      The show commands are not in any specific order.

      SUMMARY STEPS

        1.    enable

        2.    show ip arp poll

        3.    show ip interface type number unnumbered

        4.    show ip interface type number unnumbered detail


      DETAILED STEPS
        Step 1   enable

        Enables privileged EXEC mode.



        Example:
        Device> enable
        Step 2   show ip arp poll

        Displays the IP ARP host polling status.



        Example:
        Device# show ip arp poll

Number of IP addresses processed for polling: 438
Number of entries in the queue: 100 (high water mark: 154, max: 1000)
Number of request dropped:
  Queue was full: 1288
  Request was throttled by incomplete ARP: 10
  Duplicate entry found in queue: 1431
        Step 3   show ip interface type number unnumbered

        Displays the status of unnumbered interface support on interfaces configured for IP.



        Example:
        Device# show ip interface loopback 0 unnumbered

Number of unnumbered interfaces with polling: 10
Number of IP addresses processed for polling: 15
Number of IP addresses in queue for polling: 4
        Step 4   show ip interface type number unnumbered detail

        Displays the detailed status of unnumbered interface support on interfaces configured for IP.



        Example:
        Device# show ip interface loopback 0 unnumbered detail

Number of unnumbered interfaces with polling: 10
Number of IP addresses processed for polling: 15
Last 10 IP addresses processed for polling:
  209.165.201.2
  209.165.201.3
  209.165.201.4
  209.165.201.5
  209.165.201.6
  209.165.201.7
  209.165.201.8
  209.165.201.9
  209.165.201.10
  209.165.201.11
Number of IP addresses in queue for polling: 4 (high water mark: 5)
  209.165.201.12
  209.165.201.13
  209.165.201.14
  209.165.201.15

        Configuration Examples for IP Unnumbered Ethernet Polling Support

        Example: Enabling Polling on an Ethernet Interface

        Device> enable
Device# configure terminal
Device(config)# interface loopback 0
Device(config-if)# ip address 209.165.200.229 255.255.240.224
Device(config-if)# exit
Device(config)# interface ethernet 0/0
Device(config-if)# ip unnumbered loopback 0 poll
Device(config-if)# end

        Example: Configuring the Queue Size and the Packet Rate for IP ARP Polling for Unnumbered Interfaces

        Device> enable
Device# configure terminal
Device(config)# ip arp poll queue 1000
Device(config)# ip arp poll rate 1000
Device(config)# end

        Additional References

        Related Documents

        Related Topic

        Document Title

        Cisco IOS commands

        Cisco IOS Master Command List, All Releases

        IPv4 Addressing commands

        Cisco IOS IP Addressing Services Command Reference

        Conceptual information about IPv4 addresses

        “Configuring IPv4 Addresses” module in the IP Addressing: IPv4 Addressing Configuration Guide

        Technical Assistance

        Description

        Link

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        http:/​/​www.cisco.com/​cisco/​web/​support/​index.html

        Feature Information for IP Unnumbered Ethernet Polling Support

        The following table provides release information about the feature or features described in this module. This table lists only the software release that introduced support for a given feature in a given software release train. Unless noted otherwise, subsequent releases of that software release train also support that feature.

        Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to www.cisco.com/​go/​cfn. An account on Cisco.com is not required.
        Table 1 Feature Information for IP Unnumbered Ethernet Polling Support

        Feature Name

        Releases

        Feature Information

        IP Unnumbered Ethernet Polling Support

        Cisco IOS XE Release 3.8S

        The IP Unnumbered Ethernet Polling Support feature provides IP unnumbered support for Ethernet physical interfaces.

        The following commands were introduced or modified: clear ip arp poll statistics, clear ip interface, ip arp poll, ip unnumbered poll, show ip arp poll, and show ip interface unnumbered.