At least one of monitoring servers is not reachable from this script

Fri Sep  8 12:43:01 2017 - [info] Executing SSH check script: save_binary_logs --command=test --start_pos=4 --binlog_dir=/data/binlog/,/var/lib/mysql,/var/log/mysql --output_file=/tmp/save_binary_logs_test --manager_version=0.57 --binlog_prefix=mysql-bin

Fri Sep  8 12:43:01 2017 - [info] HealthCheck: SSH to 172.17.0.4 is reachable.

Fri Sep  8 12:43:04 2017 - [warning] Got error on MySQL connect: 2003 (Can't connect to MySQL server on '172.17.0.4' (111))

Fri Sep  8 12:43:04 2017 - [warning] Connection failed 2 time(s)..

ssh: connect to host 172.17.0.2 port 22: No route to host

Monitoring server 172.17.0.2 is NOT reachable!

Fri Sep  8 12:43:04 2017 - [warning] At least one of monitoring servers is not reachable from this script. This is likely a network problem. Failover should not happen.