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Last updated: 270 day(s) ago (Sun Feb 24 15:01:33 2008)	Fri Nov 21 01:43:23 2008

Linux Serial Port Resource Page

I often connect the servers I manage to terminal concentrators and often these concentrators are managed by a host system usually Sun and lately on Linux. On those host systems I typically use tip or C-Kermit. But I much prefer tip since it is simple and easy to maintain by setting up the /etc/remote file.

In fact my latest problem was finding a copy of tip for Linux Redhat 8. I was not able to find a quick solution to that problem. I did find the source tree for tip in the Netbsd collection. However after starting to compile it I found errors right away since it was based on the BSD collection. Sigh!

First lets start with a little history for tip and the package of utlities it's found in UUCP.

UUCP was created around 1976 by Mike Lesk at AT&T Bell Laboratories in order to allow a simple yet configurable modem communcations network between unix hosts. Elaborate maps were created and eventually commercial services like UUNet provided UUCP connections for fifity cents a minute. This of course was all in the days before high-speed bandwidth was available or commercially viable.

"Unix-to-Unix Copy Program," said PDP-1. "You will never find a more wretched hive of bugs and flamers. We must be cautious." --DECWars

There are basically two different UUCP packages out there: Taylor named after it's creator, Ian Taylor which is derrived from the BSD variants of unix and is the adopted GNU version now and the original HoneyDanBer written in 1983 by Peter Honeyman, Dan Nowitz, and Brian Redman (also sometimes known as "HDB" and "BNU - Basic Networking Utilities") which is derrived from System V type systems and is a part of AT&T licensed systems. It is common in commercial unices like Sun Solaris and IBM AIX 4.Now tip is included in the BNU distribution but was dropped by the time Taylor was developed. The cu command is a replacement for tip and contains basically the same tilde (~) escape commands that tip does.

However Taylor UUCP is configured differently then HDB (although it is reported to support HDB file configuration - it didn't recognize /etc/remote for me). Instead of configuring /etc/remote I had to setup the file /etc/uucp/port.

Here is my sample configuration:

# This is an example of a port file. This file have the syntax compatible# with Taylor UUCP (not HDB, not anything else). Please check uucp# documentation if you are not sure how Taylor config files are supposed to # look like. Edit it as appropriate for your system.# Everything after a '#' character is a comment.# (ttyS0 means COM1)port serialtype directdevice /dev/ttyS0speed 9600An example session:

$ cu -p serialConnected.~.Disconnected.If you see this error:

cu: Access to port denied

Use chmod to change the permissions on /dev/ttyS0 as root:

# chmod 666 /dev/ttyS0

Other software that can work with serial ports on Linux is minicom.

Be sure to use the $ minicom -o option to avoid the modem initialization being sent to the server on the serial port!

Notes:

The Linux UUCP HOWTO

The Linux Serial HOWTO

Taylor UUCP configuration

Taylor (GNU) UUCP Mailing List Interface

FreeBSD UUCP Docs

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Current time in Deltona, Florida, United States [28.9002N 81.2419W | Grid: EL98jv] is Fri Nov 21 01:43:23 2008

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