Application Environment Of Static Routing; Configuring A Static Route; Configuration Prerequisites - HP 4800G Series Configuration Manual

The network administrator can configure a default route with both destination and mask being
0.0.0.0. The router forwards any packet whose destination address fails to match any entry in the
routing table to the next hop of the default static route.
Some dynamic routing protocols, such as OSPF, RIP and IS-IS, can also generate a default route.
For example, an upstream router running OSPF can generate a default route and advertise it to
other routers, which install the default route with the next hop being the upstream router.

Application Environment of Static Routing

Before configuring a static route, you need to know the following concepts:
1) Destination address and mask
In the ip route-static command, an IPv4 address is in dotted decimal format and a mask can be either
in dotted decimal format or in the form of mask length (the digits of consecutive 1s in the mask).
2) Output interface and next hop address
While configuring a static route, you can specify either the output interface or the next hop address
depending on the specific occasion. For a NULL0 or loopback interface, if the output interface has
already been configured, there is no need to configure the next hop address
In fact, all the route entries must have a next hop address. When forwarding a packet, a router first
searches the routing table for the route to the destination address of the packet. The system can find the
corresponding link layer address and forward the packet only after the next hop address is specified.
The next hop address can not be a local interface IP address; otherwise, the route configuration will not
take effect.
3) Other attributes
You can configure different preferences for different static routes so that route management policies can
be applied more flexibly. For example, specifying the same preference for different routes to the same
destination enables load sharing, while specifying different preferences for these routes enables route
backup.

Configuring a Static Route

Configuration Prerequisites

Before configuring a static route, you need to finish the following tasks:
Configure the physical parameters for related interfaces
Configure the link-layer attributes for related interfaces
Configure the IP addresses for related interfaces
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