Inittab – Huh What’s It Good For?

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We run a CentOS-5 based hylafax server with external serial modems. We are transitioning to an Asterisk system using IAXmodem running on CentOS-6.

On the CentOS-5 system to start the fax modems we added these lines to inittab:

# Add fax lines and always ALWAYS run “telinit q” after making a change. fax1:2345:respawn:/usr/sbin/faxgetty ttyS0
fax2:2345:respawn:/usr/sbin/faxgetty ttyS1

On the CentOS-6 host we did this, in accordance with the instructions provided in the various README files and man pages.

# send IA00:2345:respawn:/usr/bin/iaxmodem ttyIAX0
# receive mo00:2345:respawn:/usr/sbin/faxgetty ttyIAX0
# send IA01:2345:respawn:/usr/bin/iaxmodem ttyIAX1
# receive mo01:2345:respawn:/usr/sbin/faxgetty ttyIAX1

However, when I do an init q the faxgetty instances do not start. If I run faxgetty from the command line in detached mode for each of them
(faxgetty -D ttyIAX0) then they do start. The iaxmodem instances are started from an init.d script as far as I can tell. They appear and disappear with service iaxmodem start and stop in any case and they most certainly do not respawn if the service is stopped.

So, my question is: Does inittab have any use on el6 systems? What is its replacement? In other words, how do I accomplish what I am told to do with respect to iaxmodem and faxgetty that formerly worked in inittab and now evidently does not?

One thought on - Inittab – Huh What’s It Good For?

  • What you’ve described above works with CenOS 5 running sysv-init. It doesn’t work with CentOS 6 because sysv-init has been replaced by upstart. That, in turn, will end up being replaced by systemd when 7
    eventually comes out. About the only thing that /etc/inittab is used for under upstart or systemd is for the initial run level. You might want to read up on the upstart documentation and look at the contents of the /etc/init directory. The /etc/init.d directory contains the sysv-init init scripts. The /etc/init directory (no .d) has configuration files for upstart. Upstart can start sysv services and run sysv-init style init scripts as well.

    Regards, Mike