One Master Node removes and adds cluster nodes on regular base

[Thomas_Tomski]

Hello,

The problem was the same as here:

Node disconnects every hour

ES 2.1.0 When you say it removed and re-adds, does it mean it drops the node and re-adds the node, making many shards go unassigned and have to be assigned again? This is exactly what is happening. I see cluster goes into yellow every hour and many shards become unassigned.

It was solved by modifying the sysctl parameters:

 # Reduce keep alive values to increase frequency of keep alive packets sent across network in order to prevent ElasticSearch nodes losing connection between each other
net.ipv4.tcp_keepalive_time = 600
net.ipv4.tcp_keepalive_intvl = 60
net.ipv4.tcp_keepalive_probes = 20

Cheers!