Automatic switching

[azzana___]

We own a SG200 and we'd like to know if it is possible to automatically switch between two internet access point depending on their accessibility.

Our problem is that we have two internet access (fiber and ADSL in case fiber broke down) and we want to keep reaching internet.

Currently, we plug one access point et unplug the other.

Is there a way to connect the two access and switch between them (and prefer fiber if it's available) ?

Thanks for your help !

[chris noon]

You could use IP SLAs to track both interfaces and switch between them based on reach-ability.  E.G. ping google through both interfaces and if one fails to respond change the metric of the route and the routing table would automatically switch to the other route.

http://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst4500/12-2/44sg/configuration/guide/Wrapper-44SG/swipsla.html

[azzana___]

Thanks for your answer but after some research I've find out that SG200 don't have this capabilities.

Any other idea ? ;)

[chris noon]

I assume you have a fiber ISP router and a ADSL ISP router and both of these connect to the SG200, like the image attached.

[azzana___]

Yes indeed. But it seems that IP SLAs is not available on SG200.

[chris noon]

You could do the following which is a little more manual than IP SLA but more automated than your current solution.

Add the following command for your fibre circuit:

# ip route 0.0.0.0 0.0.0.0 [interface for fibre link] 1

This will configuresa default route to the fibre link with a metric of 1 (lowest preffered).

Then add the following command:

# ip route 0.0.0.0 0.0.0.0 [interface for ADSL link] 5

This configures a default route to the ADSL link with a metric of 5.  This will not be used as the fibre link has a lower metric.

If the fibre link fails simply enter the following command to switch it over to the ADSL link:

# ip route 0.0.0.0 0.0.0.0 [interface for fibre link] 10