Saturday, December 10, 2011

Enhanced Object Tracking and IP SLA

 Enhanced OBJECT Tracking (EOT).

  • It is used to solve issues where line protocol is not good indicator of end to end connectivity i.e router may not be directly connected to another router so it feasible one side could be showing down and the other side showing as up
  • It  can track interface,line status,threshold percentage,boolean expression
  • it is often used in conjuction with ip sla
  • track resolution can be used to define an action
Commands

track 1 interface s0/0 line-protocol
track 2 interface s0/1 line-protocol
track 3 interface s0/2 line-protocol

track 100 list threshold precentage
object 1
object 2
object 3
threshold percentage up 75

IPSLA

Type of IP SLA

UDP Jitter - one way delay jitter
ICMP Path Jitter- hop by hop jitter + packetloss
UDP Jitter for VOIP- measure round trip delay,onwe wau delay + emulate specfic protocols
UDP Echo- measures rtt for UDP traffic
ICMP Echo- measure rtt for full path
ICMP Path echo- measure round trip hop by hop
HTTP- measures round trip to retrieve web page
FTP- measure round trip to transfer a file
DHCP- measures round trip to get an ip address
DNS- measures dns lookup time
DLSW- measure peer tunnel response time
Frame-relay - measure wait + random delay
RTP VOIP- sends real voip rtp stream where voip jitter sends simulated stream

Commands

Ip sla 1
icmp-echo 155.0.0.9 source ip 10.11.11.1
frequency 5
timeout 2000
ip sla schedule 1 start-time now life forever



LAB


ok so in the scenerio r5 has a default route via s0/0/0 or s0/1/0  in the event we can not ping the ip address of http://www.google.com/ fictional address of 155.10.0.4 s0/0/0 will be declared down and s0/1/0 will become default route




so first thing is to configure the  ip route on r5
ip route 0.0.0.0 0.0.0.0 s0/0/0 10 track 2  -- ok so we have givenip route with                                                adminm distance of 10 it is watching                                                the track object result
we now give a backup route via s0/1/0 setting the admin distance of 20 so it will not be selected for the routing table unless the s0/0/0 path is not availible

ip route 0.0.0.0 0.0.0.0 s0/0/0 20

Ok so we configure our ip sla to send ping to 155.10.0.4 with source of 10.229.254.1
it will send pings every 5 seconds. And failure is if it does not hear back in 2000 miliseconds
(config) ip sla 1
(config-ip-sla) icmp-echo 155.10.0.4 source-ip 10.229.254.1
(config-ip-sla) frequency 5
(config-ip-sla) timeout 2000

we need to schdule this so we start monitoring now and we want indefinite even if router reboot
(c0nfig) ip sla schedule 1 start-time now life forever
we need to configure a track now to associate the ip sla with
so track 2 monitors whether the ip sla state is up or down. Down being failure to recieve reply from google.com
(config) track 2 ip sla 1 state
if you notice the ip route watches the state of this track 2 interface if the ip sla fails to ping the track 2 is down and the route is taken out of the routing table and the route via s0/0/0 is installed. So we have proactively monitored a upstream event.

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