1755Use the undo keepalive command to disable the keepalive function.By default, the GRE keepalive function is disabled.With the GRE keepalive function enabled on a tunnel interface, the device sendsGRE keepalive packets from the tunnel interface periodically. If no response isreceived from the peer within the specified interval, the device retransmits akeepalive packet. If the device still receives no response from the peer after akeepalive packet is transmitted for the maximum number of attempts, the localtunnel interface goes down and keeps down until it receives a keepaliveacknowledgement packet from the peer.Related command: interface tunnel.Example # Set the GRE keepalive interval to 20 seconds and the maximum number ofattempts for transmitting a keepalive packet to 5. system-view[Sysname] interface tunnel 0[Sysname-Tunnel0] keepalive 20 5sourceSyntax source { ip-address | ipv6-address | interface-type interface-number }undo sourceView Tunnel interface viewParameter ip-address: Source IPv4 address for a tunnel interface.Ipv6-address: Source IPv6 address for a tunnel interface.interface-type interface-number: Type and number of the source interface for atunnel interface. The interface type can be Ethernet, VLAN, serial, ATM, tunnel, orloopback.Description Use the source command to specify the source address or interface for a tunnelinterface.Use the undo source command to remove the configuration.By default, no source address or interface is configured for a tunnel interface.Note that:■ The source address of a tunnel interface is the address of the interface sendingGRE packets and is usually the destination address of the peer tunnel interface.■ Two or more tunnel interfaces using the same encapsulation protocol musthave different source addresses and destination addresses.
