HP VPN Firewall Appliances VPN Command Reference

6
gre recursion
Use gre recursion to specify a value for the Recursion Control field in the GRE header.
Use undo gre recursion to restore the default.
Syntax
gre recursion recursion-value
undo gre recursion
Default
The value of the Recursion Control field in the GRE header is 0, which means not to limit the number of
encapsulations.
Views
Tunnel interface view
Default command level
2: System level
Parameters
recursion-value: Specifies the value for the Recursion Control field in the GRE header, in the range of 1
to 7.
Usage guidelines
Devices of some vendors require that, for example, the Recursion Control field in the GRE header should
not be 0, and will discard GRE packets whose Recursion Control field is 0. To solve this problem, you
must use this command on the HP device to adjust the Recursion Control field.
Adjusting the value of the Recursion Control field does not affect how many times the HP device
encapsulates a GRE packet. It only enables the HP device to work with some vendors' devices.
Examples
# Set the Recursion Control field in the GRE header to 1.
<Sysname1> system-view
[Sysname1] interface tunnel 3
[Sysname1-Tunnel3] gre recursion 1
keepalive
Use keepalive to enable the GRE keepalive function to detect the status of the tunnel interface and set the
keepalive interval and the maximum number of attempts for transmitting a keepalive packet.
Use undo keepalive to disable the keepalive function.
Syntax
keepalive [ seconds [ times ] ]
undo keepalive
Default
The GRE keepalive function is disabled.