A cool tip here if you've ever lost access to your primary or secondary SRX device, you can still access them via another cluster node.

For example, if you want to gain access to node1 in the cluster from the Primary device, node0, you can do so using the 'request routing-engine login node <node_id>' command syntax as instrumented below:

FW01-A_Primary> request routing-engine login node 1

-- JUNOS 11.4R10.3 built 2013-11-15 06:56:30 UTC

This is very helpful if you don't have OOB serial access oryour company operates it's application environments in co-location facilities and it's not as easy to walk over to the DC and plug in a console cable.