HP NC3131 Fast Ethernet Server Adapter - Manual (Page 18)

2-6 Compaq NC3131 Fast Ethernet Server Adapter User Guide
Connecting and Using
Loop-Back Plugs
RJ-45 loop-back plugs are supplied in the adapter and upgrade module packages. A fiber loop-
back plug is available in a spare parts kit. Install these plugs in any unused RJ-45 or fiber port
on the adapter or module, as described in the following table. If the plug is not installed, you
may get a cable fault or reduced functionality on the adapter or module, depending on the
operating system you are running.
RJ-45 Loop-Back Plug
Each kit for the NC3131 adapter and the NC3132 upgrade module contains a loop-back plug.
This loop-back plug consists of a single RJ-45 connector on a truncated cable. After you install
the adapter or adapters in the server, and connect the server to the network, insert this plug into
any unused 10/100 port on either the adapter or the upgrade module. For example, if you install
an NC3132 upgrade module in an NC3131 adapter and connect two ports to the network, you
may have up to two unused ports. In this example, you should insert the provided loop-back
plugs into the unused ports.
In addition, you can use the loop-back plug to diagnose the status of the adapter port without the
adapter being on a live network. When you insert the loop-back plug into the port, the LNK
LED for the port will light if the adapter port is operational, indicating that the link is
established.
Figure 2-4. Inserting a loop-back plug into an RJ-45 port