GRE and IP-IP tunnel configuration

To bind an IP/GRE or IP-IP tunnel to a private tunnel SAP, the ip-tunnel command should be added under the SAP. To configure the tunnel as an IP/GRE tunnel, the gre-header command must be present in the configuration of the ip-tunnel. To configure the tunnel as an IP-IP tunnel, the ip-tunnel configuration should have the no gre-header command. When configuring a GRE or IP-IP tunnel, the dest-ip command specifies an IPv4 or IPv6 address (private) of the remote tunnel endpoint. A tunnel can have up to 16 dest-ip addresses. If any of the dest-ip addresses are not contained by a subnet of the local private endpoint, then the tunnel does not come up. In the CLI sub-tree under ip-tunnel, there are commands to configure the following:

A private tunnel SAP can have only one ip-tunnel sub-object (one GRE or IP-IP tunnel per SAP).

The show ip tunnel command displays information about a specific IP tunnel or all configured IP tunnels. The following information is provided for each tunnel:

The following is an example of the output of the show ip tunnel tunnel-name command.

A:config>service>vprn>if>sap>ip-tunnel# show ip tunnel "ipv6-gre"
===============================================================================
IP Tunnel Configuration Detail
===============================================================================
Service Id       : 1                    Sap Id           : tunnel-1.private:1
Tunnel Name      : ipv6-gre
Description      : None
GRE Header       : Yes                  Delivery Service : 2
GRE Keys Set     : False                
GRE Send Key     : N/A                  GRE Receive Key  : N/A
Admin State      : Up                   Oper State       : Up
Source Address   : 2001:db8::1:2:3:4
Remote Address   : 3ffe:1::2
Backup Address   : (Not Specified)
Oper Remote Addr : 3ffe:1::2
DSCP             : ef                   
Reassembly       : inherit              
Clear DF Bit     : false                IP MTU           : max
Encap IP MTU     : 1400                 
Pkt Too Big      : true                 
Pkt Too Big Numb*: 100                  Pkt Too Big Intvl: 10 secs
Oper Flags       : None
Last Oper Changed: 02/09/2015 15:22:38  
Host MDA         : 1/2                  

-------------------------------------------------------------------------------
Target Address Table
-------------------------------------------------------------------------------
Destination IP                          IP Resolved Status
-------------------------------------------------------------------------------
172.16.1.2                              Yes
2001:db8::2                             Yes
-------------------------------------------------------------------------------

===============================================================================
IP Tunnel Statistics: ipv6-gre
===============================================================================
Errors Rx        : 0                    Errors Tx        : 0
Pkts Rx          : 0                    Pkts Tx          : 0
Bytes Rx         : 0                    Bytes Tx         : 0
Key Ignored Rx   : 0                    Too Big Tx       : 0
Seq Ignored Rx   : 0                    
Vers Unsup. Rx   : 0                    
Invalid Chksum Rx: 0                    
Key Mismatch Rx  : 0                    
===============================================================================

===============================================================================
Fragmentation Statistics
===============================================================================
Encapsulation Overhead                 : 44
Pre-Encapsulation
    Fragmentation Count                : 0
    Last Fragmented Packet Size        : 0
Post-Encapsulation
    Fragmentation Count                : 0
    Last Fragmented Packet Size        : 0
===============================================================================
===============================================================================