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# 1  
Old 02-12-2002

Hi all,

I have to disconnect the console of a live system which runs sunSolaris 2.7

Do I have to do a "kbd -a" before ??

The keyboard is connected to the monitor and the monitor is plugged in to the live system.

Is the above command going to work OK??
Does anyone came across that b4 ??

Thanks very much in advance.
# 2  
Old 02-12-2002
If the system you have has a key which can be placed in a secure position, then the system will ignore the software defaults. Probably safer than just using the kbd command.

Watch out for problems booting - when you remove a console it can hang the boot sequence. Check out

Last edited by thehoghunter; 02-12-2002 at 01:45 PM..
# 3  
Old 02-12-2002
Is there any more specific site I can check, I can not find what I am looking for there? What can I search for ??

There is also a key, does that mean that if I turn the key to the lock symbol I can just unplug the monitor?? The keyboard is connected to the monitor.

Please help

# 4  
Old 02-12-2002
You mentioned the keyboard is plugged into the monitor - Do you mean a dumb terminal? Is the 'monitor' plugged into the serial port (a or b)?

Here is the info -

The definition of a headless system is one that does not have an attached
keyboard or does not have a Sun console. It will by default send the boot
information out serial port A if the keyboard or console are not attached.
Serial port B can also be used.

Attach using NULL modem cable to:

-An ascii terminal- For example, Wyse terminal
-Another Sun workstation that has a Sun console
-A Network terminal concentrator/server

Technical Support does not recommend booting off a serial port with a
modem attached or not having any type of console.

A console allows the ability to send a break signal dropping the
system to the OK prompt for diagnostics. The console device is

What needs to be configured on Solaris

A. Open Boot Prom:

OK> setenv output-device ttya
OK> setenv input-device ttya

Note: the above is not necesary on tty A if the keyboard is disconnected.
It is necessary to change these setting for serial port B regardless.

Additional settings:

Syntax for changing Open Boot Prom value:

OK> setenv ttya-rts-dtr-off false
OK> setenv ttya-ignore-cd true

Use printenv to verify the following settings:

To change:
OK> setenv ttya-mode 9600,8,n,1,-

Run the "reset" command to make the above settings take effect

OK> reset

B. The terminal type, /etc/inittab and port monitors

Do not start port monitor services for the serial port. Verify with pmadm -l.
Make sure there are no listings for the tty port that is acting as the
console. (Solaris 2.5 ttya and ttyb have port monitor services enabled for
modem logins by default- These services need to be removed)

To remove type:

pmadm -p zsmon -r -s <SVCTAG>

SVCTAG will be ttya or ttyb.

/etc/inittab takes care of setting the console port characteristics
with the following line:

co:234:respawn:/usr/lib/saf/ttymon -g -h -p "`uname -n` console login: "
-T sun -d /dev/console -l console -m ldterm,ttcompat

By default the console terminal type is "sun" specified with the
-T option above. This means that for ascii terminals vi will not work.
Inorder for programs like vi to work the TERM variable needs to be
changed to match the "personality" of the terminal.
This can be done by modifing -T in /etc/initab to 'wyse30' (for example)
or changing the TERM variable in .login, .profile, or .cshrc or at
the command line, for example:

setenv TERM wyse30

C. Sending a Break Signal

Unpluging the serial cable is the equivalent to sending a break
and will bring the Sun box down to the OK prompt. If the cable was
not attached during bootup plugging it in may send a break. When
a Network Terminal Server is rebooted this will also send a break
and bring the Sun boxes down to the OK prompt.

What needs to be configured on the terminal

Ascii terminals have a setup mode. For the wys30 <shift><setup> keys
will bring up the terminals parameters. Use the arrow keys and
the space bar to proceed thru the settings.

settings: 8 data bits, no parity, 1 stop bit (8, none, 1)
baud: Use 9600!
personality (modes) : vt100, wyse60, etc needs to match the Solaris
TERM variable

Related SRDB's

SRDB ID: 13758
SYNOPSIS: Headless 4.x connected to Network Terminal Server displays garbage until login.

SYNOPSIS: Ways to Send Break (L1-A) to remotely logged into serial console device.

SYNOPSIS: Solaris 2.4/2.5 Modem configuration

SYNOPSIS: Warning - ttymon cannot allocate controlling tty on /dev/console,

SYNOPSIS: Allowing root logins over modem lines in /etc/ttytab


OpenBoot Command Reference Manual
A. Setting Up a TIP connection
# 5  
Old 02-12-2002
YES, the monitor is physically connected to a serial port and the keyboard is connected to the back of the monitor. I have turned the key to the lock position. I also did a "kbd -a disable", nothing happened. Do you think that it is now safe to just disconnect the monitor or I have to set the appropriate env.
This is a live system.

Thanks very much for your help.
# 6  
Old 02-13-2002
As the monitor was connected to the serial port A it was safe to do it. I had no problem.

Thanks for your answers.
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