HP (Hewlett-Packard) HP-UX 11i v2 Manuale Utente

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Configuring gated
Specifying Route Preference
Chapter 3
94
Specifying Route Preference
gated
 maintains a routing table that consists of the route information
learned from OSPF and from other active routing protocols, such as RIP
or EGP. You can also configure static routes in the
/etc/gated.conf
file
with one or more
static
The
gated
 routing pool can therefore contain multiple routes to a single
destination. When multiple routes exist, the route chosen by
gated
 is
determined by the following (in order of precedence):
The
preference
 value associated with the route. The
preference
value is a number in the range from 0 (most preferred) to 255 (least
preferred). Routes from different sources have different default
preference values. For example, OSPF routes within a given AS have
a preference value of 10. Table 3-3 shows the default preference
values of various types of routes.
If multiple routes use the same protocol and have the same
preference value, the route with the lowest metric or cost is chosen.
If metric or cost is the same, the router with the lowest IP address is
chosen.
Table 3-3
Default Preference Values of Routes
Route Type
Preference
/etc/gated.config
 Configuration
Interface
routes
0
Can be changed with
interface
statement in Interface class.
OSPF inter-
and intra-areas
10
Cannot be changed.
Internal
default
20
Generated by BGP or EGP when
routing information is learned from
a peer.
ICMP Redirect
30
Can be changed with
redirect
statement in Protocol class.
SNMP
50
Can be changed in
SNMP
statement in
Protocol class.