This section discusses troubleshooting the tty subsystem:
The system records the number of getty processes spawned for a particular tty in a short time period. If the number of getty processes spawned in this time frame exceeds five, then the Respawning Too Rapidly error is displayed on the console and the port is disabled by the system.
The tty stays disabled for about 19 minutes or until the system administrator enables the port again. At the end of the 19 minutes, the system automatically enables the port, resulting in the spawning of a new getty process.
Note: The following applies to Hayes-compatible modems.
- See Sending AT Commands with the cu Command
- See your modem documentation for further information.
chdev -l ttyName -a Login=disable
After running this command, the tty does not become enabled after a system restart.
The following sections discuss important error logging files and commands and common error report messages relating to ttys.
This command deletes entries from the error log. The entire log can be erased with errclear 0 or entries with specified error ID numbers, classes, or types can be removed.
This command generates an error report from entries in the system error log. The most used format for this command is errpt -a | pg, which generates a detailed report starting with the most current errors.
This file stores instances of errors and failures encountered by system. The errlog file tends to become quite lengthy. If not cleared on a regular basis, it can occupy quite a bit of space on your hard disk. Use the errclear command mentioned previously to clean out this file.
The errids.h header file correlates error IDs with error labels.
|Core Dump||Software program abnormally terminated||This error is logged when a software program abnormally ends and causes a core dump. Users might not be exiting applications correctly, the system might have been shut down while users were working in application, or the user's terminal might have locked up and the application stopped.|
|Errlog On||Errdaemon turned on||This error is logged by the error daemon when the error logging is started. The system automatically turns off error logging during shutdown.|
|Lion Box Died||Lost communication with 64-port concentrator||This error is logged by the 64-port concentrator driver if communications with the concentrator are lost. If you receive this error, check the date and time stamp to see if user might have caused this message to occur. A series of these errors can indicate a problem with the 64-port adapter or its associated hardware.|
|Lion Buffero||Buffer overrun: 64-port concentrator||This error occurs when the hardware buffer in a 64-port concentrator is overrun. If device and cabling allow, try adding request to send (RTS) handshaking to the port and device. Also try lowering the baud rate.|
|Lion Chunknumc||Bad chunk count: 64-port controller||This error occurs when the value for the number of characters in a chunk does not match the actual values in the buffer. This error may indicate a problem with the hardware; try running diagnostics on devices.|
|Lion Hrdwre||Cannot access memory on 64-port controller||This error is logged by the 64-port concentrator driver if it is unable to access memory on the 64-port controller.|
|Lion Mem ADAP||Cannot allocate memory: ADAP structure||This error is logged by the 64-port concentrator driver if the malloc routine for the adap structure fails.|
|Lion Mem List||Cannot allocate memory: TTYP_T List||This error is logged by the 64-port concentrator driver if the malloc routine for the ttyp_t list structure fails|
|Lion Pin ADAP||Cannot pin memory: ADAP structure||This error is logged by the 64-port concentrator driver if the pin routine for the adap structure fails.|
|SRC||Software program error||This error is logged by the System Resource Controller (SRC) daemon in the event of some abnormal condition. Abnormal conditions are divided in three areas: failing subsystems, communication failures, and other failures.|
|Lion Unkchunk||Unknown error code from the 64-port concentrator||Error Code: Number of characters in the chunk received.|
|TTY Badinput||Bad ttyinput return||Error Code: System error code (see sys/errno.h). This is logged by the tty driver if ttyinput routine returns an error.|
|TTY Overrun||Receiver overrun on input||The sending device is ignoring flow control and overloading the hardware buffer on the adapter. This occurs before the driver accesses the hardware FIFO. Try adding rts handshaking to the port and to device (if possible).|
|TTY TTYHOG||TTYHOG overrun||The sending device is ignoring flow control. This error occurs after the hardware first in/first out (FIFO) has been accessed and has written to the software buffer. In other words, the tty hog error is logged because the buffer in which incoming characters are placed is overflowing. When the buffer is about three-fourths full, the device driver notifies the hardware (in this case, tty) to send the XOFF char to the sender to stop sending data. If the sender continues to send data and the buffer is not emptied, the device driver flushes the buffer and logs the error message in the error log.|
|TTY Parerr||Parity/Framing error on input||This error indicates parity errors on incoming data to asynchronous ports on a character-by-character basis.|
|TTY Prog PTR||Software error: T_HPTR field invalid||This error is logged by the tty driver if t_hptr pointer is null.|