L1-A and Annex

2007-12-25 8:38:00

Dear fellow admins,

This summary has been delayed until we could test solutions.

The problem:

Turning off an Annex (and many other brands) Terminal server which serves as

the console for approximately 32 Sun servers causes all the Suns connected to

the Annex to halt.

The winning answer was from Torsten Metzner, om@uni-paderborn.de, who pointed

me to Hal Stern's excellent paper "serial.ps", available ftp from

dartvax.dartmouth.edu : pub/sun/serial.ps.

The paper contains a circuit diagram which pointed us to solution. Using Hal's

diagram we contacted:

NuData Inc.

32 Fairview Avenue

Little Silver, NJ 07739-9976

Ron Sealy Engineering (908) 842-5757

Who sent us an A-D -> I/0 serial switch box they market to share one console

between 5 Suns. The switch box had the circuitry we needed to prevent the

"break" signal on disconnection of the terminal.

They are building this circuitry into a "gender-bender" sized connector that we

will insert between ttya on the sun and the cable to the Annex. While we do not

yet have the final product, we anticipate that it will work based on our

testing of the switch.

The cost of each gizmo in quantities of about 100 will be +-$80.

After installing the circuit all works normally. L1-A will still halt the

system, but disconnecting or powering off the Annex has no ill effect on the

Suns. This solution should work on all terminals and terminal servers which

exhibit this problem. For the worried - Wyse terminals do, vt-200 do not. Most

terminal servers do.

Several of the replies suggested kernel mods which would also solve the problem

in various ways. We elected to go with the hardware solution since the numerous

systems involved are administered by many different groups and hey - some

people never get the word.

Many thanks to:

Richard Doty (rad@twig.com)

Jim Ahokas (csfb1!next8!ahokas@uunet.UU.NET)

--
___________________________________________________
Steve Swaney
swanes@eq.gs.com
1 (212) 902-4526 (desk)
1 (917) 859-4229 (cellular)

Actived: 0 answers; - size: 3590 bytes; - view related info - Similar thread

Got something to say?

You must be logged in to post a comment.

thatsjava.com