Docker Trusted Registry - Unable to satisfy available container slot

Question

I am trying to install the Docker Truster Registry (DTR). I am executing the following command:

docker run -it --rm \
docker/dtr install \
--ucp-url https://10.000.000.125 \
--ucp-node node123 \
--dtr-external-url https://10.000.000.97 \
--ucp-username admin --ucp-password admin \
--ucp-ca "$(cat ucp-ca.pem)" \

I am getting the following error back:

ERRO[0000] Make sure that there is a node in your UCP cluster where port 80 and port 443 are open. Also confirm that all UCP node have the DTR images or can obtain them from Docker Hub.
FATA[0000] Problem running container 'dtr-phase2' from image 'docker/dtr:2.0.2': Couldn't create container 'dtr-phase2' from image 'docker/dtr:2.0.2': Error response from daemon: Unable to find a node that satisfies the following conditions
[available container slots]
[node==node123 node!=node123]

I am able to ping the server from where I am trying to install the DTR. I do not know what that issue means. I appreciate any help

Answer 1

I've tried to reproduce the problem you have (using trial DTR license).

I assume the node, you are installing DTR on, is already joined to the UCP cluster and you can test connection from the DTR node to the TCP port 443 on a UCP controller.

According to the documentation:

dtr-external-url, is the public IP or domain name where DTR can be reached

So, precisely speaking, --dtr-external-url should be 10.000.000.97 in your case (although I agree the parameter name is a bit misleading).

It's hard to advise something without knowing any details about your UCP configuration (such as networking, etc). But considering the error message, I would advise to verify that hostname of your DTR node is indeed set to node123 and is correctly resolved to 10.000.000.97.