11: VIP Routes
UDP Tunneling
The UDP tunneling feature of ManageLinx allows any host on subnet A to send UDP
packets. Once a VIP route has been configured, it will carry both TCP and UDP traffic.
However, the nature of UDP requires additional details—described below—to allow the
receiving device to send UDP datagrams in the opposite direction.
The underlying assumption for UDP tunneling is that a responding device uses the
source address of the packet it received when it wants to send a reply to the original
sender.
UDP VIP Route Types
ManageLinx supports the following types of UDP VIP routes.
Uni-directional
—Allows a host on subnet A to send UDP datagrams to Dev1, but
does not expect Dev1 to send any response.
Bi-directional
—Allows Host1 on subnet A to send a UDP packet to Dev1, while
attempting to assure that there are sufficient resources to support a UDP packet
going back from Dev1 to Host1. This is done by creating a VIP route from a VIP on
DSC2 to Host1.
There are 2 types of
Bi-directional
routing:
Automatic Reverse Mapping
—selects an unused VIP in the auto VIP pool to use to
send data from device B back to Host 1. This automatic route will remain open for a
few minutes even if there is no activity.
Manual Reverse Mapping
—lets you manually configure Virtual IP routes in both
directions: a Virtual IP route from Host 1 to Device B and a VIP route from DSC B to
Host1. A static route thus established remains in effect until changed.
ManageLinx User Guide
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