2-6Compaq NC3134 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 section. 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 NC3134 adapter and the NC3135 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 adapters in the server and connect the server to the network, insert this plug into any unused 10/100 ports on either the adapter or the upgrade module. For example, if you install an NC3135 upgrade module in an NC3134 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
