HP ProCurve 7102dl Reference Manual page 376

SROS Command Line Interface Reference Guide Global Configuration Mode Command Set
interface tunnel <id>
Use the interface tunnel command to create a virtual tunnel interface and enters the Tunnel Configuration
command set. See Tunnel Configuration Command Set on page 1144 for details. Use the no form of this
command to delete a configured virtual tunnel interface.
Syntax Description
<id> Specifies the numerical tunnel interface identifying label (valid range: 1 to 1024).
Default Values
By default, there are no configured tunnel interfaces.
Functional Notes
A tunnel may become operational only under the following conditions:
1. The tunnel must have an IP address defined.
2. A valid source address or interface must be configured.
3. A valid destination address must be configured.
4. The physical interface used as the source for the tunnel must be operational.
5. The tunnel can not be in a recursive routing loop.
keepalive <period> <retries>
6. If keepalives are enabled, keepalive processing must be successful. See
on page 1192 for details.
Technology Review
A tunnel interface enables standard point-to-point encapsulation between two links. Each endpoint must
have a unique tunnel configured. Tunneling allows an arbitrary payload protocol to be encapsulated within
a delivery protocol to provide point-to-point communications. The tunnel alone does not provide encryption
or any other means of high security. The tunnel interface is not a physical interface, so traffic will be routed
to the tunnel by the routing engine for encapsulation or decapsulation and typically forwarded out a
physical interface. A common tunnel implementation is the use of a GRE tunnel to transport IP multicast
traffic, such as that used by routing protocols across a link that only has IP unicast connectivity (such as
IPSec).
Usage Examples
The following example creates a tunnel interface (labeled 1) and enters the Tunnel Configuration mode:
ProCurve(config)#interface tunnel 1
ProCurve(config-tunnel 1)#
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