messaging publisher stuck

To reproduce this behaviour I added two dummy notifiers in the sink, and a third one(tcp) which actually works, like this
~~~
      publishers:
          - notifier://172.17.1.121:5666/?driver=amqp&topic=cloud1-metering
          - notifier://172.17.1.122:5667/?driver=amqp&topic=cloud1-metering
          - tcp://127.0.0.1:3060
~~~

Even though the first 2 weren't reachable, metrics were being sent to the tcp publisher. Does such a behaviour blocks messaging publisher only ? It would be helpful if you could provide some more details to reproduce it.

Could you also try out using "max_retry" parameter like
~~~
- notifier://[notifier_ip]:[notifier_port]?topic=[topic]&driver=driver&max_retry=100
~~~

I didn't use 'max_retry'.

Please try two messaging publishers, as following：
"""
      publishers:
          - notifier://$user:$password@$rabbit_server1_ip:5672?driver=rabbit&topic=cloud1-metering
          - notifier://$user:$password@$rabbit_server2_ip:5672?driver=rabbit&topic=cloud1-metering
"""

If rabbit_server1 not works('ping' with ip is ok, but 'telnet' with port failed), the messages can't publish to rabbit_server2.
#ping $rabbit_server1_ip
PING $rabbit_server1_ip 56(84) bytes of data.
64 bytes from $rabbit_server1_ip: icmp_seq=1 ttl=61 time=0.392 ms
...
#telnet $rabbit_server1_ip 5672
Trying $rabbit_server1_ip. . .
telnet: connect to address $rabbit_server1_ip: Connection refused