NAME
irdpd - internet router discovery protocol daemon
SYNOPSIS
irdpd [-bd] [-U udp-device] [-I ip-device] [-o priority-
offset]
DESCRIPTION
Irdpd looks for routers. This should be a simple task, but
some routers are hard to find because they do not implement
the router discovery protocol. This daemon collects infor-
mation that routers do send out and makes it available.
At startup irdpd sends out several router solicitation
broadcasts. A good router should respond to this with a
router advertisement.
If a router advertisement arrives then no more solicitations
are sent. The TCP/IP server has filled its routing table
with the info from the advertisement, so it now has at least
one router. If the advertisement is sent by a genuine
router (the sender is in the table) then the irdpd daemon
goes dormant for the time the advert is valid. Routers send
new adverts periodically, keeping the daemon silent.
Otherwise irdpd will listen for RIP (Router Information Pro-
tocol) packets. These packets are sent between routers to
exchange routing information. Irdpd uses this information
to build a routing table.
Every now and then a router advertisement is sent to the
local host to give it router information build from the RIP
packets.
OPTIONS
-b Broadcast advertisements instead of sending them to the
local host only. This may be used to keep (non-Minix)
hosts alive on a net without adverts.
-d Debug mode, tell where info is coming from and where it
is sent. Debugging can also be turned on at runtime by
sending signal SIGUSR1 or turned off with SIGUSR2.
-o priority-offset
Offset used to make the gateway's preferences collected
from RIP packets look worse than those found in genuine
router adverts. By default -1024.
SEE ALSO
inet(8), boot(8), dhcpd(8), inetd(8), nonamed(8).
BUGS
This daemon has gone out of favour thanks to dhcpd, that
also does router solicitations among other things.
Under standard MINIX 3 this daemon can't listen to both IRDP
and RIP at the same time, so it starts out with IRDP. It
switches over to RIP if it can't find a router, or if it
threatens to lose its router. It does not switch back.
AUTHOR
Kees J. Bot (kjb@cs.vu.nl)