H3C S9500E Series, Configuration Manual, Page: 23 / 459

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IP routing protocol version
IPv4 routing protocols: RIP, OSPFv2, BGP4, and IS-IS.
IPv6 routing protocols: RIPng, OSPFv3, BGP4+, and IPv6 IS-IS.
Routing protocols and routing preference
Different routing protocols can find different routes to the same destination. However, not all of
those routes are optimal. Only one protocol can uniquely determine the current optimal route to
the destination at a particular moment. For route selections, each routing protocol (including static
routes) is assigned a preference. The route found by the routing protocol with the highest
preference is preferred.
Table 1 lists some routing protocols and the default priorities for routes found by them.
Table 1 Routing protocols and routing preferences
Routing approach Preference
DIRECT 0
OSPF 10
IS-IS 15
STATIC 60
RIP 100
OSPF ASE 150
OSPF NSSA 150
IBGP 255
EBGP 255
UNKNOWN 256
•
The smaller the preference value, the higher the preference (priority).
•
The preference for a direct route is always 0, which cannot be changed. You can manually configure
preferences for any other route type.
•
Each static route can be configured with a different preference.
•
IPv4 and IPv6 routes have their own respective routing tables.