--- description: Known Docker Engine issues in Docker Cloud keywords: Engine, issues, troubleshoot redirect_from: - /docker-cloud/faq/docker-errors-faq/ title: Known issues in Docker Cloud --- This is a list of known issues with current versions of Docker Engine along with our recommended workaround. You might encounter these errors in Docker Cloud. --- ## Error message: Get i/o timeout *Get https://index.docker.io/v1/repositories/\/images: dial tcp: lookup \ on \:53: read udp \:53: i/o timeout* #### Description The DNS resolver configured on the host cannot resolve the registry's hostname. #### GitHub link N/A #### Workaround Retry the operation, or if the error persists, use another DNS resolver. You can do this by updating your `/etc/resolv.conf` file with these or other DNS servers: nameserver 8.8.8.8 nameserver 8.8.4.4 --- ## Error message: 500 Server Error: userland proxy *500 Server Error: Internal Server Error ("Cannot start container \: Error starting userland proxy: listen tcp 0.0.0.0:\: bind: address already in use")* #### Description Docker Cloud is trying to deploy a container publishing a port which is already being used by a process on the host (like the SSH server listening in port `22`). #### GitHub link N/A #### Workaround Either choose another port, or SSH into the node and manually stop the process which is using the port that you are trying to use. --- ## Error message: 500 Server Error: bind failed *500 Server Error: Internal Server Error ("Cannot start container \: Bind for 0.0.0.0:\ failed: port is already allocated")* #### Description Docker Cloud is trying to deploy a container publishing a port which is already used by another container outside of the scope of Docker Cloud. #### GitHub link N/A #### Workaround Either choose another port, or SSH into the node and manually stop the container which is using the port that you are trying to use. --- ## Error message: 500 Server Error: cannot start, executable not found *500 Server Error: Internal Server Error ("Cannot start container \: [8] System error: exec: "\": executable file not found in $PATH")* #### Description The `run` command you specified for the container does not exist on the container. #### GitHub link N/A #### Workaround Edit the service to fix the run command. --- ## Error message: Timeout when pulling image from the registry *Timeout when pulling image from the registry* #### Description Timeouts occur when pulling the image takes more than 10 minutes. This can sometimes be caused by the Docker daemon waiting for a nonexistent process while pulling the required image. #### GitHub link docker/docker#12823 #### Workaround Restart the `dockercloud-agent` service (`sudo service dockercloud-agent restart`) on the node, or restart the node.