Cisco 7000 Hardware Installation And Maintenance page 213

Following is an example of the show controller cxbus command that shows an interface port (2/0)
that has an EIA/TIA-232 DTE cable attached, and a second port (2/1) that does not have a cable
attached:
7000# show controller cxbus
Switch Processor 7, hardware version 11.1, microcode version 1.4
512 Kbytes of main memory, 128 Kbytes cache memory, 299 1520 byte buffers
Restarts: 0 line down, 0 hung output, 0 controller error
FSIP 2, hardware version 3, microcode version 1.0
Interface 16 - Serial2/0, electrical interface is RS-232 DTE
31 buffer RX queue threshold, 101 buffer TX queue limit, buffer size 1520
Transmitter delay is 0 microseconds
Interface 17 - Serial2/1, electrical interface is Universal (cable unattached)
31 buffer RX queue threshold, 101 buffer TX queue limit, buffer size 1520
To change the electrical interface type or mode of a port online, you replace the serial adapter cable
and use software commands to restart the interface and, if necessary, reconfigure the port for the new
interface. At system startup or restart, the FSIP polls the interfaces and determines the electrical
interface type of each port (according to the type of port adapter cable attached). However, it does
not necessarily repoll an interface when you change the adapter cable online. To ensure that the
system recognizes the new interface type, shut down and reenable the interface after changing the
cable.
Perform the following steps to change the mode or interface type of a port by replacing the adapter
cable. First replace the cable, then shutdown and bring up the interface with the new cable attached
so that the system recognizes the new interface. If you are replacing a cable with one of the same
interface type and mode, these steps are not necessary (simply replace the cable without interrupting
operation).
Step 1 Locate and remove the adapter cable to be replaced.
Step 2 Connect the new cable between the FSIP port and the network connection. Tighten the
thumbscrews at both ends of the cable to secure it in the ports.
Step 3 At the privileged level of the EXEC specify the port address, shut down the interface, and
write the configuration to NVRAM. Add additional configuration commands, if any, before
you exit from the configuration mode (before you enter ^z).
7000> en
Password: sshhhhh
7000# configure terminal
int serial 3/5
shutdown
^z
7000# write mem
Step 4 Enter the configuration mode again and bring the port back up.
7000# configure terminal
int serial 3/5
no shutdown
^z
These steps will prompt the system to poll the interface and recognize the new interface immediately.
When configuring a port for a DCE interface for the first time, or when setting up a loopback test,
you must set the clock rate for the port. When you connect a DCE cable to a port, the interface will
remain down, the clock LEDs will remain off, and the interface will not function until you set a clock
rate (regardless of the DCE mode default).
Installing and Configuring Processor Modules
Maintenance 5-209