Disable logins thru modem

[Kim Kendall]

Is there a way to disallow logins thru a tty port that has a modem attached?

We have a modem that we want to use for outgoing pages ONLY.

[Sridhar Bhaskarla]

Hi Kim,

As long as you do not spawn any getty process for the modem, your system will not allow logins.

Do a 'ps -ef|grep getty' and see if there are any getty processes other than console. If so, then compare them against /etc/inittab and make sure the lines that correspond to your modem (like tty0p1) are taken/commented out. Refresh init by doing a 'init q'.

-Sri

[Kim Kendall]

the inittab has respawn...

a0:3:respawn:/usr/sbin/getty -h tty2a2 57600

We want the system to be able to dial out anytime, but just don't want it to answer incoming calls.

[James R. Ferguson]

Hi Kim:

I believe you want:

a0:3:off:/usr/sbin/getty -h tty2a2 57600

Regards!

...JRF...

[Steven E. Protter]

For it to answer calls in the first place you have to configure it.

Here is how to unconfigure it:

as root

sam

SAM Peripheral Devices ->
SAM Terminals and Modems

select your modem
actions modify modem

Uncheck the box to take incoming calls.
Make sure the box for outgoing calls is still checked.

Exit sam.

I do this once every couple of years so don't bother remembering how to do it from the command line.

SEP

[Sridhar Bhaskarla]

Hi,

getty process is responsible for answering the incoming calls. Disabling it will not disable dial-outs.

Disable it and then try dialing out. You can always turn it back on by taking the comment off and running the 'init q' command.

-Sri

[Kim Kendall]

What version are you running? My version of Sam doesn't offer those options.

[Darren Prior]

Hi Kim,

The replies that mention changing the respawn to off in the modem entry in inittab are accurate. You can also do this as suggested in SAM, though if you'd originally modified /etc/inittab manually it will replace your entry with SAM's default.

You can also configure the modem so that it won't answer the phone line even if a getty is present. Check your modem's handbook - MultiTech modems generally use ATS=0 to set autoanswer to off. This command can be sent by connecting to the modem using kermit or cu, and should be followed by the correct command to save the settings in the modem's memory.

regards,

Darren