SRX

What does Active / Active data plane for the SRX series really means ? 

does it mean that it will have the same RG on both nodes active ? or simply means that we have two RGs on the nodes (one RG active on one node the other one is passive )  that serves the SAME traffic as of load balancing ?

Thanks , 

You are correct that active / active does NOT refer to having two route engines functioning. One route engine is always active and the other is always passive. However you can have interfaces on either node in an active state. So an active / passive scenario is one where one node has the active route engine and all active interfaces are on that node.

Active / active has interfaces active on both nodes.

Hope that helps explain it!

For active/active you need two RG and one will be configured to be active on each node of the cluster.  The whole concept of failover is still present within each RG.  So if one physical device does fail then the other will pick up the traffic for both groups.

The documentation for SRX is really thin on active/active issues.  I've attached a graphic from the ScreenOS documentation that shows the concept pretty well.  This also illustrates that you need to take special care with setting default routes when you are in active/active mode to prevent all traffic from running through only one RG.

both explanations helped alot ! 

so there's no such thing as having the same RG active on both node handling the same traffic simultanously. BUT two RGs handling the same transit traffic.

there's much misconception about the active/active scenario that makes most customers believe that the two nodes will act as a single ( combined ) one node with double throughput , double everything.

this makes it much clear.