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New Member

IP SLA by tracking TCP port


I am using dual homing for internet connection.

I want to force all traffic from the LAN to access the internet via Router #1 while Router #2 is a backup.

I want to track TCP port 6000 (communication between a certain host on the internet talking to a certain PC on the LAN) and in case TCP port 6000 is down, to route the traffic between them via Router #2.

This is the only traffic passing between the LAN and the host on the internet.

Now I have two static routing lines configured with different cost.

I want to use IP SLA, tracking TCP port 6000 and switch to the backup Router in case TCP port 6000 is down.

Can some one  post a simple configuration to do so?

Thank you.



Re: IP SLA by tracking TCP port

One way you could do it is setup HSRP between both routers and on the active router you could  track something upstream by using pings or telnet TCP port 6000 , but give up the active role once it loses either telnet or ping.

so you can configure IP SLA to ping a host and associate this SLA to a track.

On the HSRP configuration, you can use the track option instead of the interface.

Please read this chapter and at the bottom of the chapter, a HSRP example is illustrated.


New Member

Re: IP SLA by tracking TCP port

Hi Francisco.

Thank you for your reply.

But, I am looking for something specific, I have some limitations not mentioned.

Can I track TCP port 6000 using IP SLA and then using a switch over between the routers with the track option in the static routing in case of a crash in the application running over TCP port 6000?

HSRP should not be a part of the solution and neither ICMP echo (IP address can be OK but the application may crash).

All solution should be based on IP SLA tracking TCP port 6000.