HP-UX Reference (11i v3 07/02) - 4 File Formats (vol 8)

r
ramd.conf(4) ramd.conf(4)
The preference is not used to control the selection of routes within an Interior Gateway Protocol. This is
accomplished automatically by the protocol based on the metric value. Each route has only one preference
value associated with it, even though the preferences can be set at many places in the configuration file.
The last or the most specific preference value set for a route is the value used. The route with smallest
preference value is the active route.
The best route is selected as follows:
1. The route with the best (numerically smallest) preference is selected.
2. If the routes are from the same protocol, the one with the lowest metric is selected.
3. If the routes have the same metric value, the route with the lowest numeric next hop address is
selected.
Assigning Preferences
RAMD assigns a default preference to each source from which it receives routes. The preference values
range from 0 - 255, with the lowest number indicating the most preferred route.
The default preference values for different types of routes are:
Direct route 0
IS-IS route 15
Static route 60
RIPng route 100
BGP route 170
The syntax of the preference configuration statement is:
preference (ripng|bgp|isis|static|direct) preference-value
;
This configuration statement assigns preference values for routes learned from routing protocols.
Interface Configuration Statement
The interface configuration statement configures the primary address and the preference for an interface.
The syntax of the interface configuration statement is:
interface interface-name {
[preference preference-value
;]
[
alias primary IPv6-address;]
[
aliases-nh (primary|lowestip|keepall);]
};
where the following means:
preference preference-value
;
Sets the preference for routes to this interface when the interface is up. The default preference is 0.
alias primary IPv6-address;
Specifies a primary address for this interface. It overrides the address that ramd determines to be
primary.
aliases-nh (primary|lowestip|keepall);
Specifies the address that ramd installs as the next hop for interface routes, when multiple addresses
are assigned to an interface like the ServiceGuard environment.
primary Replaces the next hop address with the primary address for all the direct routes of an
interface.
lowestip Replaces the next hop address with the lowest IPv6 address for all the direct routes of an
interface.
keepall ramd does not modify any direct routes for this interface. The ramd daemon does all
the route modification in its routing table.
ICMPv6 Redirect Message Processing
ramd processes the ICMPv6 redirect request and decides whether to accept the redirect. If the redirect is
accepted, ramd installs a route in its routing table with the protocol as redirect. ramd deletes the redirect
routes from its routing table after 3 minutes.
342 Hewlett-Packard Company − 4 − HP-UX 11i Version 3: February 2007