If you have configured the Docker Engine 18.09 with the
HTTPS_PROXY environment variables, then the following error may prevent joining or promoting manager nodes:
Error response from daemon: manager stopped: can't initialize raft node: rpc error: code = Unavailable desc = all SubConns are in TransientFailure, latest connection error: connection error: desc = "transport: Error while dialing dial tcp: lookup proxy.example.com on 192.168.121.1:53: no such host"
This error can be found on the command line in response to
docker swarm join with a manager token, or in
docker info on the node that is being promoted after promotion fails.
- Docker Engine prior to 18.09.04
- Joining or promoting a manager node
- HTTP HTTPS proxy configured (configuration visible
An update to the Docker Swarm gRPC libraries unintentionally caused them to start respecting proxy environment variables
A patch at https://github.com/docker/swarmkit/pull/2802 has been proposed to address this issue by restoring the original behavior of ignoring proxy environment variables. This have been fixed in Docker Engine 18.09.4 : Fixed issue for swarm nodes not being able to join as masters if http proxy is set. [moby/moby#36951]
Add all manager IP addresses to the
NO_PROXY environment variable using the instructions at docs.docker.com
Note: you must specify individual manager node Swarm IPs in
NO_PROXY. Docker EE Engine 18.09 and lower do not support CIDR notation for