Although, the above document is specific to datacenter SRX series devices configuration the behavior is the same for branch series SRX as well.
Instead of achieving LAN side redundancy via VRRP, we can configure RGs on both LAN and WAN side for redundancy purposes. In a nutshell, we will be aggregating one physical interface from Node0 and another physical interface from Node1, form a reth interface(pseudo-interface) and put that reth interface into a Redundancy Group(RG). You will get to know once you go through the above document.
I like your suggestion with the aggregation in one reth, but how would you set-up both links then if they have their own WAN facing IP?
Our uplink carrier gives us 5.x.x.186 for uplink 1 and 5.x.x.184 for uplink 2, so I thought that I should connect uplink 1 to node 0 and set the ip address on the physical interface and same thing for the second... Can that also be achieved with a reth?
Chassis Cluster provides RE redundancy as you stated (control-plane redundancy), however the for data-plane redundancy you need the Reth interfaces. A reth interface is basically a bundle on 2 interfaces (one from each node) but only the link of one of the nodes is active at a time. This makes sure that if one node goes down (hence its interface), the Reth will continue to be up and the traffic will be processed by the other node. Physically the network will look like this:
But logically/virtually, it will look like there is only one SRX and that each Reth is only one interface :
Reth 0 will be the redundant gateway that you were looking for the servers via VRRP. Reth 1 and 2 are the two uplinks that you were looking towards your ISP, and in this case both uplinks will have physical redundancy.
I hope this helps you.
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