So far me included that error is often just simple DNS where the container is pointing to the wrong IP or doesn’t have an entry.
docker ps -a #list all containers.
docker stop [container-id] #stop container
docker rm [container-id] #delete container
docker images #list all images
docker rmi [image-id] #delete image
docker exec -i -t [container-id] /bin/sh #run shell inside container
docker logs [container-id] #view log
docker info #environment setup
https://docs.docker.com/engine/reference/commandline/docker/1
Check your DNS on the server, clients and inside the container.
nslookup subdomain.example.com
Check your certs on the server, clients and inside container.
openssl s_client -connect subdomain.example.com:443
you can enter the container with docker exec -i -t [container-id] /bin/sh and install dnsutils there
might just be an edit to /etc/hosts and install nano to complete
docker run -t -d -p 127.0.0.1:9980:9980 -e 'domain=nextcloud\\.vote4u\\.org\\.uk' --dns=192.168.1.2 --restart always --cap-add MKNOD collabora/code
If you are on a local subnet and have local dns then you can pass that address with the above.
Its the same as the standard docker run but just passes the dns server ip with dns=192.168.1.2
docker info & docker logs will tell much and maybe post your findings as there are some distro differences.