Technical data

7. Client/Server interface imond

7.1. imon-Server imond

imond is a network-capable server program that responds to certain queries or accepts com-

mands that can control the router.

imond also controls the Least-Cost-Routing. It uses the conﬁguration ﬁle /etc/imond.conf,

that is created automatically from the variables ISDN_CIRC_x_XXX from the ﬁle conﬁg/isdn.txt

and other at boot time by a shell script.

imond runs permanentely as daemon and listens on TCP/IP port 5000 and the device

/dev/isdninfo.

All possible commands that can be sent to TCP/IP port 5000:

The TCP/IP port 5000 is only reachable from the masqueraded LAN. Access from remote

is blocked by the ﬁrewall conﬁguration by default.

Imond supports two user levels: the user and the admin mode. For both levels you can

set a password using varIMOND_PASS and/or IMOND_ADMIN_PASS. Then, clients are forced by

imond to submit a password. As long as no password has been submitted, only the commands

“pass” and“quit” are accepted. Others are rejected.

If you want to further restrict access, e.g. only allow access from a single computer, the

ﬁrewall conﬁguration has to be changed.

At present this is not possible using the standard conﬁguration ﬁles conﬁg/base.txt. You

will have to change the ﬁle /etc/rc.d/rc322.masq.

The commands

enable/disable/dialmode dial/hangup route reboot/halt

Can be globally enabled/disabled using the conﬁguration variables IMOND_XXX (see “Conﬁg-

uration”).

From a Unix/Linux computer (or a Windows computer in a DOS box) you can easily try it

out: Type

telnet fli4l 5000 \# or the appropriate name of the fli4l-Routers

and you will be able to directly enter the listed commands and look at the output.

For example after entering “help” the help is shown, after “quit” the connection to imond is

terminated.

7.1.1. Least-Cost-Routing – how it works

imond contructs a table (time table) from the conﬁguration ﬁle /etc/imond.conf (which is

created on bootup from the conﬁg variables ISDN_CIRC_x_TIMES and others). It contains a

complete calendar week in a raster of 1 hour (168 hours = 168 Bytes). But the table only

contains the circuits that have a default route deﬁned.

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