OpenStack Controller zeromq sending truncated message to compute node on compute restart

* OpenStack Controller trying to send huge data (details of all VMs in the node) to a compute node on restart of that compute node.

* But message got truncated and compute node not getting complete message from controller.

* Issue may be the TCP Buffer size of OpenStack control node.

* Try to increase TCP Buffer size in OpenStack control node.

http://fosshelp.blogspot.in/2015/07/how-to-ubuntu-linux-increase-tcp-buffer.html