My appliance is directly connected to the internet with a public IP address, that's why I think is my only option. Is there a workarround to set up Full HA with an /30 network for my external interface? Thanks in advance.
This is not a Full HA specific question, refer to the following SK: Configuring Cluster Addresses on Different Subnets
That said, I would consider carefully whether you want to use a Full HA cluster or not.
You may wish to read through some of the SKs linked here: How to install Full HA cluster on Check Point appliances
Thanks Dameon for your reply, but I've allready read both SK and neither of them answer my question. The thing is that I want both my appliances to be in a cluster and act as my border router, we don't have a router to use as a border gateway. Here's a pic to understand better:
Is it possible?
The Configuring Cluster Addresses on Different Subnets SK is how you would achieve what you are after.
More specifically, your Cluster IP would be the publicly routable IP you have.
You would also have a private (non-routable) subnet for the external interfaces--this is required for ClusterXL.
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