HP 6125XLG R2306-HP 6125XLG Blade Switch Layer 3 - IP Routing Configuration Gu - Page 12

IP routing basics IP routing directs IP packet forwarding on routers based on a routing table. This chapter focuses on unicast routing protocols. For more information about multicast routing protocols, see IP Multicast Configuration Guide. Routing table A router maintains at least two routing tables: a global routing table and a FIB. The FIB table contains only the optimal routes, and the global routing table contains all routes. The router uses the FIB table to forward packets. For more information about the FIB table, see Layer 3-IP Services Configuration Guide. Table 1 categorizes routes by different criteria. Table 1 Route categories Criterion Destination Categories • Network route-The destination is a network. The subnet mask is less than 32 bits. • Host route-The destination is a host. The subnet mask is 32 bits. Whether the • Direct route-The destination is directly connected. destination is directly connected • Indirect route-The destination is indirectly connected. Origin • Direct route-A direct route is discovered by the data link protocol on an interface, and is also called an "interface route." • Static route-A static route is manually configured by an administrator. • Dynamic route-A dynamic route is dynamically discovered by a routing protocol. To view brief information about a routing table, use the display ip routing-table command: display ip routing-table Destinations : 19 Routes : 19 Destination/Mask 0.0.0.0/32 1.1.1.0/24 1.1.1.0/32 1.1.1.1/32 1.1.1.255/32 2.2.2.0/24 80.1.1.0/24 ... Proto Pre Direct 0 Direct 0 Direct 0 Direct 0 Direct 0 Static 60 OSPF 10 Cost 0 0 0 0 0 0 2 NextHop 127.0.0.1 1.1.1.1 1.1.1.1 127.0.0.1 1.1.1.1 12.2.2.2 80.1.1.1 A route entry includes the following key items: • Destination-IP address of the destination host or network. • Mask-Mask length of the IP address. 1 Interface InLoop0 Vlan1 Vlan1 InLoop0 Vlan1 Vlan2 Vlan3