Experience Sharing Routing backup and load balancing

Recently, some netizens asked me questions about multiple external route backups and SLB. Due to the time relationship, I simply wrote the configuration .... the following uses dual-External route backup as an example .. A multi-outer line is nothing more than adding a corresponding policy route on the basis of the original .... if any omission exists, please advise ....

The premise is that all interfaces and other basic configurations are complete.

(1) You can add two default routes to the two lines: the first line takes priority. If the first line fails, it will automatically jump to the second line.

Ip route 0.0.0.0 0.0.0.0 x. x

Ip route 0.0.0.0 0.0.0.0 y. y

(2) If the first line is normal and needs to be loaded by the second line, you can configure a policy route based on (1. As follows:

A. configure policies for some CIDR blocks. For example, redirect 192.168.1.0 and 192.168.2.0 to some loads on the y. y. y line.

Access-list 12 permit 192.168.1.0 0.0.255

Access-list 12 permit 192.168.2.0 0.0.255

Route-map yy permit 10 (defines the policy yy)

Match ip address 12 (matching Control List 12)

Set ip next-hop y. y (set the next hop address, that is, the next router interface address through which the data packet passes [gateway])

B. Make policies for some hosts. For example, jump host 192.168.3.11 and host 192.168.4.12 to y. y. y. y line load (by default, these two CIDR blocks use the first default route, that is, x. x. x. x ).

Access-list 101 permit ip host 192.168.3.11 any

Access-list 101 permit ip host 192.168.4.12 any

Route-map yy permit 20 (defines the policy yy)

Match ip address 101 (matching control list 101)

Set ip next-hop y. y (set the next hop address, that is, the next router interface address through which the data packet passes [gateway])

In this way, by default, except for the network segments and hosts defined in the preceding Policy Routing, all hosts in other network segments use the Line x. x. x. x connects to the external network, if x. x. x. if the line x fails, the default route will change to y. y. y. y. y. y. y line, so it will not be affected .... article entry: csh responsible editor: csh