WAN REDUNDANCY - TWO ISP

Two ISP connected to Your head office if ISP 1 (primary link) link goes down 

automatically  ISP 2 (backup link) link will activate. what are the 

methods we can configure?

WAN Redundancy : 

WAN Redundancy: Method 1:

 Basic redundancy WAN LINK:

 R1(CONFIG)# IP ROUTE 0.0.0.0 0.0.0.0 10.2.1.1

 R1(CONFIG)# IP ROUTE 0.0.0.0 0.0.0.0 10.3.1.1  10

 Here 10 is administrative distance... if first route fails 

 second route will work.   (Secondary link that is backup link)

WAN Redundancy: Method 2: Automatic failover method: IP SLA

R4#config t
Enter configuration commands, one per line.  End with CNTL/Z.

R4(config)#ip sla 10
R4(config-ip-sla)#icmp-echo 10.0.0.1
R4(config-ip-sla-echo)#timeout 1000
R4(config-ip-sla-echo)#frequency 1
R4(config-ip-sla-echo)#exit

R4(config)#ip sla schedule 10 start-time now life forever

R4(config)#track 20 ip sla 10 reachability
R4(config-track)#exit

R4(config)#ip route 0.0.0.0 0.0.0.0 10.0.0.1 track 20 1
R4(config)#ip route 0.0.0.0 0.0.0.0 10.0.0.2 50
R4(config)#exit

TROUBLE SHOOTING

R4#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 = 268/277/292 ms
R4#tra




R4#traceroute 3.3.3.3

Type escape sequence to abort.
Tracing the route to 3.3.3.3

  1 10.0.0.1 68 msec 200 msec 200 msec
  2 13.0.0.3 396 msec 332 msec 332 msec



R4#show track 20
Track 20
  IP SLA 10 reachability
  Reachability is Up
    2 changes, last change 00:03:44
  Latest operation return code: OK
  Latest RTT (millisecs) 132
  Tracked by:
    STATIC-IP-ROUTING 0




R1(config)#interface ethernet 1/0
R1(config-if)#shutdown



R4#
*Jun 12 06:49:40.051: %TRACKING-5-STATE: 20 ip sla 10 reachability Up->Down


R4#show track 20
Track 20
  IP SLA 10 reachability
  Reachability is Down
    3 changes, last change 00:00:29
  Latest operation return code: Timeout
  Tracked by:
    STATIC-IP-ROUTING 0



R4#traceroute 3.3.3.3

Type escape sequence to abort.
Tracing the route to 3.3.3.3

  1 10.0.0.2 140 msec 200 msec 140 msec
  2 32.0.0.3 272 msec 336 msec 268 msec





R4#show ip route track-table
 ip route 0.0.0.0 0.0.0.0 10.0.0.1 track 20 state is [down]



R4#show ip sla statistics
IPSLAs Latest Operation Statistics

IPSLA operation id: 10
Type of operation: icmp-echo
        Latest RTT: NoConnection/Busy/Timeout
Latest operation start time: *06:53:01.035 UTC Fri Jun 12 2015
Latest operation return code: Timeout
Number of successes: 343
Number of failures: 382
Operation time to live: Forever


R1(config)#interface ethernet 1/0
R1(config-if)#no shutdown




R4#
*Jun 12 06:53:45.051: %TRACKING-5-STATE: 20 ip sla 10 reachability Down->Up




R4#show ip route track-table
 ip route 0.0.0.0 0.0.0.0 10.0.0.1 track 20 state is [up]


R4#show ip sla statistics
IPSLAs Latest Operation Statistics

IPSLA operation id: 10
Type of operation: icmp-echo
        Latest RTT: 184 milliseconds
Latest operation start time: *06:54:51.035 UTC Fri Jun 12 2015
Latest operation return code: OK
Number of successes: 412
Number of failures: 402
Operation time to live: Forever


R4#sh track 20
Track 20
  IP SLA 10 reachability
  Reachability is Up
    4 changes, last change 00:01:57
  Latest operation return code: OK
  Latest RTT (millisecs) 148
  Tracked by:
    STATIC-IP-ROUTING 0