New (Gen 4) Nodes

Just a short notice to announce the arrival of the 4th generation of ORBIT nodes ( ​http://www.orbit-lab.org/wiki/Hardware/hNodes/cNodeVer4 ): sb1 now has two lower-power gen4 nodes (which unfortunately means that we don’t have original ORBIT nodes in any of the sandboxes anymore), while high-powered gen4 nodes replaced gen3 nodes supporting USRP X310s in the main grid. Unfortunately, in addition to being faster, new nodes also require more modern kernels (we are still looking into whether we can backport all the necessary drivers) which means that older images, including current Ubuntu 12.04 based baseline.ndz won't work with the new nodes. Currently, the only image that works with these new nodes is baseline-gen4.ndz (that image will also work with all gen3 nodes but will not boot properly on the gen1 and gen2 nodes - newer Ubuntu distributions don’t support non-pae platforms suggesting the end of universal images that run on all ORBIT nodes).