show line

To display the status of a line, use the command show line. This is not a privileged command and can be executed by any user. On an eight-port terminal server, show line gives output like this:

Router>show line
 TTY TYP Tx/Rx A Modem Roty AccO AccI Uses Noise Overruns
 0 CTY - - - - - 0 0 0/0
 1 TTY 9600/9600 - - - - - 3 542 0/0
* 2 TTY 9600/9600 - - - - - 1 0 0/0
 3 TTY 38400/38400 - RIisCD - - - 1 0 0/0
I 4 TTY 38400/38400 - inout - - - 25 0 0/0
I 5 TTY 38400/38400 - inout - - - 3940 0 0/0
I 6 TTY 38400/38400 - inout - - - 1483 0 0/0
I 7 TTY 38400/38400 - inout - - - 364 0 0/0
I 8 TTY 38400/38400 - inout - - - 12 0 0/0

Table 4-2 describes the fields in this report.

Table 4-2. Fields in a show line display

Column	Meaning
1st column	I = line is idle; * = line is active.
TTY	Actual line number.
TYP	Type of line: CTY (console), AUX, TTY, VTY, LPT.
TX/RX	Transmit and receive baud rates for this line.
A	Autobaud (automatic baud rate detection) is active.
Modem	Type of modem signal configured for this line (callin, callout, cts-req, dtr-act, inout, RIisCd).
Roty	Rotary group configured for this line.
AccO, AccI	Access lists for this line, both output and input (see access-class in Chapter 17).
Uses	Number of connections made to this line since the router was booted.
Noise	Number of times noise was detected on this line. Can be used to gauge line quality.
Overruns	Number of buffer overruns that have occurred on this line, in the format hardware/software. Hardware overruns occur when the hardware receives data from the software faster than it can process it. Software overruns occur when the software receives data from the hardware faster than it can process it. A bad cable could cause overruns.

You can retrieve more detailed information by selecting a single line:

Router>show line 5
 Tty Typ Tx/Rx A Modem Roty AccO AccI Uses Noise Overruns
A 5 TTY 38400/38400 - inout - - - 3969 0 0/0

Line 5, Location: "", Type: ""
Length: 24 lines, Width: 80 columns
Baud rate (TX/RX) is 38400/38400, no parity, 1 stopbits, 8 databits
Status: Ready, Active, No Exit Banner, Async Interface Active
Capabilities: Hardware Flowcontrol In, Hardware Flowcontrol Out
 Modem Callout, Modem RI is CD, Line usable as async interface
Modem state: Ready
Special Chars: Escape Hold Stop Start Disconnect Activation
 ^^x none - - none
Timeouts: Idle EXEC Idle Session Modem Answer Session Dispatch
 0:00:30 never none not set
Session limit is not set.
Time since activation: 2:08:08
Editing is enabled.
History is enabled, history size is 10.
Full user help is disabled
Allowed transports are lat telnet rlogin mop. Preferred is lat.
No output characters are padded
No special data dispatching characters
Modem hardware state: CTS DSR DTR RTS
Line is running PPP for address 192.101.187.165.
0 output packets queued, 1 input packets.
 Async Escape map is 00000000000000000101000000000000
Group codes: 0
 Interface Async5: (passive, compression on)
 Rcvd: 5711 total, 4516 compressed, 0 errors
 0 dropped, 0 buffer copies, 0 buffer failures
 Sent: 5085 total, 4032 compressed,
 138729 bytes saved, 3943290 bytes sent
 1.3 efficiency improvement factor
 Connect: 16 rx slots, 16 tx slots, 1275 long searches, 765 misses
 84% hit ratio, five minute miss rate 0 misses/sec, 1 max

The first part of this report has the same format given in Table 4-2. However, the rest of the report goes into great detail about the line's characteristics. Table 4-3 shows what these additional fields mean.

Table 4-3. Fields in a show line for a single port

Field	Meaning
Line	TTY line number.
Location	Value of the location keyword set for this line. See location in Chapter 17.
Type	Value specified by the line configuration.
Length	Terminal display length in characters.
Width	Terminal display width in characters.
Baud	Transmit (TX) and receive (RX) baud rates.
Status	State of the line (ready, connected/disconnected, active/inactive, exit banner).
Capabilities	How or for what this line can be used.
Modem state	Control state of the modem. If not Ready, suspect a modem problem.
Special chars	Settings of characters defined for this line.
Timeouts	Timeouts as specified by the configurations.
Session limit	Maximum number of sessions for this line. Controlled by the session-limit command.
Time since activation	Time elapsed since line activation (i.e., how long the line has been considered active).
Editing	Whether command-line editing is enabled.
History	Length of the command history buffer. Set by the user with the history command.
Full user help	Whether the full-help command has been activated for this line.
Transport methods	Transport mechanisms allowed on this line. See the transport command in Chapter 17 for more information.
Character padding	See the padding command in Chapter 17.
Data dispatching characters	Whether any data-dispatching characters are configured. See dispatch-character in Chapter 17 for more information.
Line protocol	The protocol and address specified for this line.
Output/input packets	Queued packet counts for this line.
Group codes	AT group codes for this line.