Floating Static for Redanduncy

A Floating static route is a route that  used for a backup route ,and it  has a higher administrative distance then the current route and dynamic routing protocol being used in a routing table.In this way, the floating static route will only appear in the routing table if the dynamically learned route is lost.

Configuring a floating static route is very easy with this command ip route n.n.n.n s.s.s.s nh.nh.nh.nh
but need to add a number to the end of the command ranging between 1-255 whereas 255 is “unreachable”.Any route given the administrative distance of 255 WILL NOT be installed in the routing table under any circumstances. Keep in mind the default administrative distance of a static route is 1.

Configuring floating static

R2(config)#do sh run | s route
ip route 3.3.3.3 255.255.255.255 10.1.13.3
ip route 3.3.3.3 255.255.255.255 10.1.14.3 30

R2(config)#do sh ip route | b Gate
Gateway of last resort is not set

     3.0.0.0/32 is subnetted, 1 subnets
S       3.3.3.3 [1/0] via 10.1.13.3
     10.0.0.0/24 is subnetted, 2 subnets
C       10.1.14.0 is directly connected, FastEthernet2/0
C       10.1.13.0 is directly connected, FastEthernet1/0

Verify the routing table

R2(config-if)#do sh ip route 3.3.3.3

Routing entry for 3.3.3.3/32

  Known via "static", distance 1, metric 0

  Routing Descriptor Blocks:

  * 10.1.13.3

      Route metric is 0, traffic share count is 1

R2#ping 3.3.3.3

Type escape sequence to abort.

Sending 5, 100-byte ICMP Echos to 3.3.3.3, timeout is 2 seconds:

!!!!!

Success rate is 100 percent (5/5), round-trip min/avg/max = 20/40/64 ms

Tracing the route to 3.3.3.3 network

R2#traceroute 3.3.3.3

Type escape sequence to abort.

Tracing the route to 3.3.3.3

  1 10.1.13.3 112 msec 36 msec 24 msec

After Shuting down the interface fa 1/0 of R2

Traffic will go from backup route 10.1.14.3

R2(config)#int f 1/0
R2(config-if)#shutdown
R2(config-if)#
*Mar 1 00:07:03.235: %LINK-5-CHANGED: Interface FastEthernet1/0, changed state to administratively down
*Mar 1 00:07:04.235: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet1/0, changed state to down


R2(config-if)#do sh ip route 3.3.3.3
Routing entry for 3.3.3.3/32
Known via "static", distance 30, metric 0
Routing Descriptor Blocks:
* 10.1.14.3
Route metric is 0, traffic share count is 1


R2#traceroute 3.3.3.3

Type escape sequence to abort.
Tracing the route to 3.3.3.3

  1 10.1.14.3 120 msec 60 msec 48 msec

R2(config-if)#do sh ip route | b Gate

Gateway of last resort is not set

     3.0.0.0/32 is subnetted, 1 subnets

S       3.3.3.3 [30/0] via 10.1.14.3

     10.0.0.0/24 is subnetted, 1 subnets

C       10.1.14.0 is directly connected, FastEthernet 2/0