I have Graylog working with ES.
I have 2 nodes and one elected as Master and the slave is Master eligible. I have installed KOPF on each one.
However, after a few days of ES being started, i cannot load the KOPF information on the WEB UI. After 15 minutes it re-appears and the cluster goes back to being Green. 15 mins or so later same happens, either KOPF cannot load information ( http://i.imgur.com/QghoQnM.jpg ) or the cluster goes red or yellow and the error i get is here ( http://i.imgur.com/hrEt6ik.jpg )
At first i thought it was RAM but i have upgraded the RAM on the VM and upped the Heap Usage. If i restart ES on the master, everything goes back to normal for a few days until the problem appears again. During the time, im unable to query the ES index either (Using Glog) until i restart ES then i'm able to search my logs. What could be going wrong? It seems the main error i always get is " No active Master, switching to basic mode". I keep losing my master.