IBM System x3500 Service Manual page 17

COM 2 connector: Connect a 9-pin serial device to this connector. This connector
can also be redirected in the Configuration/Setup Utility program for use with the
baseboard management controller (BMC) or Remote Supervisor Adapter II SlimLine
to control the server remotely. Do not connect any 9-pin serial devices to this
connector when it is configured for use with the BMC or Remote Supervisor Adapter
II SlimLine.
Note: When this connector is configured for use with the server management, do
not connect any other 9-pin serial devices to this connector.
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Chapter 1. Introduction