Merge pull request #1831 from carmstrong/etcd_500

fix(contrib/coreos): bump etcd peer heartbeat to 500ms

Author: carmstrong

contrib/coreos/user-data

@@ -9,8 +9,8 @@ coreos:
     peer-addr: $private_ipv4:7001
     # give etcd more time if it's under heavy load - prevent leader election thrashing
     peer-election-timeout: 2000
-    # heartbeat interval should ideally be 1/4 or 1/5 of peer election timeout, but that's a long time...
-    peer-heartbeat-interval: 200
+    # heartbeat interval should ideally be 1/4 or 1/5 of peer election timeout
+    peer-heartbeat-interval: 500
   fleet:
     # We have to set the public_ip here so this works on Vagrant -- otherwise, Vagrant VMs
     # will all publish the same private IP. This is harmless for cloud providers.