Switching to VoIP

This is the Title of the Book, eMatter Edition

Copyright © 2007 O’Reilly & Associates, Inc. All rights reserved.

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Chapter 3: Linux as a PBX

If you use the Red Hat init script, make sure /etc/rc.d/rc.local calls it

instead of calling Asterisk directly as in the first method. Regardless of

which method you choose, make sure you’re loading the right mod-

ules (wcfxo or wcfxs) prior to the line in which Asterisk is launched.

Securing the Asterisk Instance

By default, Asterisk runs as root—the user account with total, unrestricted power.

This is generally considered a bad idea, and it’s the reason Apache, the web server,

doesn’t usually run as root. If Asterisk is compromised by an ill-willed network

prowler, it’s possible that the intruder could gain the power of root. That is, unless

you make Asterisk run as a less godly user.

To do this, create a user called “asterisk” by issuing the Red Hat

adduser command

(other Unixes could use

useradd instead):

# adduser -c "Asterisk PBX" -d /var/lib/asterisk asterisk

Next, you’ll need to alter Asterisk’s make file, located at /usr/src/asterisk/Makefile.

Using Pico or your favorite text editor, find the

ASTVARRUNDIR constant in the file, and

alter its definition to match what follows:

ASTVARRUNDIR=$(INSTALL_PREFIX)/var/run/asterisk

The directory referenced here needs to be writable by the user running Asterisk, and

the directory normally used should be writable