450: timer expired while reading from named pipe

Explanation

The server received a RETR command that specified a named pipe in the z/OS® UNIX file system. The server was able to open the named pipe, and was reading data from the named pipe. For the number of seconds specified by the FIFOIOTIME configuration option, the server could not read data from the named pipe. The FIFOIOTIME timer expired, which cancelled the read of the named pipe.

A possible cause of this error is that the process that writes data to the named pipe on the server host stopped writing data without closing the named pipe.

Any data sent from the server to client before the timer expired was permanently removed from the named pipe.

For more information about named pipes and the FIFOIOTIME configuration option, see the following topics:

The FIFOIOTIME (FTP client and server) statement in z/OS Communications Server: IP Configuration Reference.
The SIte subcommand in z/OS Communications Server: IP User's Guide and Commands .
The information about using z/OS UNIX System Services named pipes in z/OS Communications Server: IP User's Guide and Commands.

Example

Command:  
stat (fifoiotime  
>>> XSTA (fifoiotime  
211-Timer FIFOIOTIME is set to 31   
211 *** end of status ***    
Command:   
get /tmp/fifo.sample (rep  
>>> PORT 9,42,105,36,4,5    
200 Port request OK.    
>>> RETR /tmp/fifo.sample   
125 Sending data set /tmp/fifo.sample   
450 timer expired while reading from named pipe   
Confidence=Low for GET of /SYSTEM/tmp/CAPI/fifo.sample 
Command:

System action

The server cancels the current file transfer, and waits for the next command.

User response

Report the error to the system programmer.

System programmer response

Perform the following steps:

Increase the FIFOIOTIME configured value.
1. Issue the STAT (FIFOIOTIME command to query the current FIFOIOTIME value.
2. Use the SITE command with the FIFOIOTIME parameter to increase the FIFOIOTIME value.
If you anticipate long idle periods, consider using keepalive packets for the control and data connections. For more information about keepalive packets, see the following topics:
Determine why the process that writes to the named pipe stopped writing data, but did not close the named pipe.
Reissue the subcommand that failed when the FIFOIOTIME timer expired. Any data sent from the server to the client before the timer expired has been removed from the named pipe. You must take this into consideration before repeating the file transfer.

Problem determination

See the system programmer.

Source

z/OS Communications Server TCP/IP: FTP