gated.conf.4 (2010 09)

g
gated.conf(4) gated.conf(4)
Tracing options
There are no Redirect -specific tracing options. All nonerror messages are traced under the normal
class.
The Router Discovery Protocol
The Router Discovery Protocol is an IETF standard protocol used to inform hosts of the existence of
routers. It is intended to be used instead of having hosts wiretap routing protocols such as RIP. It is used
in place of, or in addition to statically configured default routes in hosts.
The protocol is split into to portions, the server portion which runs on routers, and the client portion that
runs on hosts. GateD treats these much like two separate protocols, only one of which may be enabled at
a time.
The Router Discovery Server
The Router Discovery Server runs on routers and announces their existence to hosts. It does this by
periodically multicasting or broadcasting a Router Advertisement to each interface on which it is
enabled. These Router Advertisements contain a list of all the routers addresses on a given interface and
their preference for use as a default router.
Initially these Router Advertisements occur every few seconds, then fall back to every few minutes. In
addition, a host may send a Router Solicitation to which the router will respond with a unicast Router
Advertisement (unless a multicast or broadcast advertisement is due momentarily).
Each Router Advertisement contains a Advertisement Lifetime field indicating for how long the advertised
addresses are valid. This lifetime is configured such that another Router Advertisement will be sent
before the lifetime has expired. A lifetime of zero is used to indicate that one or more addresses are no
longer valid.
On systems supporting IP multicasting, the Router Advertisements are by default send to the all-hosts
multicast address 224.0.0.1 . However, the use of broadcast may be specified. When Router Advertise-
ments are being sent to the all-hosts multicast address, or an interface is configured for the limited-
broadcast address 255.255.255.255, all IP addresses configured on the physical interface are included
in the Router Advertisement. When the Router advertisements are being sent to a net or subnet broad-
cast, only the address associated with that net or subnet is included.
The Router Discovery Server Statement
routerdiscovery server yes | no | on | off [ {
traceoptions trace_options ;
interface interface_list
[ minadvinterval time ]
[ maxadvinterval time ]
[ lifetime time ]
;
address interface_list
[ advertise ]|[ignore ]
[ broadcast ]|[multicast ]
[ ineligible ]|[preference preference ]
;
} ] ;
traceoptions trace_options
Specifies the Router Discovery tracing options. (See Trace Statements and the Router
Discovery specific tracing options below.)
interface interface_list
Specifies the parameters that apply to physical interfaces. Note a slight difference in conven-
tion from the rest of GateD, interface specifies just physical interfaces (such as le0, ef0
and en1), while address specifies protocol (in this case IP) addresses.
Interface parameters are:
maxadvinterval time
The maximum time allowed between sending broadcast or multicast Router Adver-
tisements from the interface. Must be no less than 4 and no more than 30:00 (30
minutes or 1800 seconds). The default is 10:00 (10 minutes or 600 seconds).
HP-UX 11i Version 3: September 2010 − 33 − Hewlett-Packard Company 33