I also faced the issue of getting an ERR_SSL_VERSION_OR_CIPHER_MISMATCH
error, using the jboss/keycloak Docker image and free certificates from letsencrypt. Even after considering the advices from the other comments. Now, I have a working (and quite easy) setup, which might also help you.
1) Generate letsencrypt certificate
At first, I generated my letsencrypt certificate for domain sub.example.com
using the certbot. You can find detailed instructions and alternative ways to gain a certificate at https://certbot.eff.org/ and the user guide at https://certbot.eff.org/docs/using.html.
$ sudo certbot certonly --standalone
Saving debug log to /var/log/letsencrypt/letsencrypt.log
Plugins selected: Authenticator standalone, Installer None
Please enter in your domain name(s) (comma and/or space separated) (Enter 'c' to cancel): sub.example.com
Obtaining a new certificate
Performing the following challenges:
http-01 challenge for sub.example.com
Waiting for verification...
Cleaning up challenges
IMPORTANT NOTES:
- Congratulations! Your certificate and chain have been saved at:
/etc/letsencrypt/live/sub.example.com/fullchain.pem
Your key file has been saved at:
/etc/letsencrypt/live/sub.example.com/privkey.pem
Your cert will expire on 2020-01-27. To obtain a new or tweaked
version of this certificate in the future, simply run certbot
again. To non-interactively renew *all* of your certificates, run
"certbot renew"
2) Prepare docker-compose environment
I use docker-compose
to run keycloak via docker. The config and data files are stored in path /srv/docker/keycloak/
.
- Folder
config
contains the docker-compose.yml
- Folder
data/certs
contains the certificates I generated via letsencrypt
- Folder
data/keycloack_db
is mapped to the database container to make its data persistent.
Put the certificate files to the right path
When I first had issues using the original letscrypt certificates for keycloak, I tried the workaround of converting the certificates to another format, as mentioned in the comments of the former answers, which also failed. Eventually, I realized that my problem was caused by permissions set to the mapped certificate files.
So, what worked for me is to just to copy and rename the files provided by letsencrypt, and mount them to the container.
$ cp /etc/letsencrypt/live/sub.example.com/fullchain.pem /srv/docker/keycloak/data/certs/tls.crt
$ cp /etc/letsencrypt/live/sub.example.com/privkey.pem /srv/docker/keycloak/data/certs/tls.key
$ chmod 755 /srv/docker/keycloak/data/certs/
$ chmod 604 /srv/docker/keycloak/data/certs/*
docker-compose.yml
In my case, I needed to use the host network of my docker host. This is not best practice and should not be required for your case. Please find information about configuration parameters in the documentation at hub.docker.com/r/jboss/keycloak/.
version: '3.7'
networks:
default:
external:
name: host
services:
keycloak:
container_name: keycloak_app
image: jboss/keycloak
depends_on:
- mariadb
restart: always
ports:
- "8080:8080"
- "8443:8443"
volumes:
- "/srv/docker/keycloak/data/certs/:/etc/x509/https" # map certificates to container
environment:
KEYCLOAK_USER: <user>
KEYCLOAK_PASSWORD: <pw>
KEYCLOAK_HTTP_PORT: 8080
KEYCLOAK_HTTPS_PORT: 8443
KEYCLOAK_HOSTNAME: sub.example.ocm
DB_VENDOR: mariadb
DB_ADDR: localhost
DB_USER: keycloak
DB_PASSWORD: <pw>
network_mode: host
mariadb:
container_name: keycloak_db
image: mariadb
volumes:
- "/srv/docker/keycloak/data/keycloak_db:/var/lib/mysql"
restart: always
environment:
MYSQL_ROOT_PASSWORD: <pw>
MYSQL_DATABASE: keycloak
MYSQL_USER: keycloak
MYSQL_PASSWORD: <pw>
network_mode: host
Final directory setup
This is how my final file and folder setup looks like.
$ cd /srv/docker/keycloak/
$ tree
.
├── config
│ └── docker-compose.yml
└── data
├── certs
│ ├── tls.crt
│ └── tls.key
└── keycloak_db
Start container
Finally, I was able to start my software using docker-compose
.
$ cd /srv/docker/keycloak/config/
$ sudo docker-compose up -d
We can see the mounted certificates within the container.
$ cd /srv/docker/keycloak/config/
$ sudo docker-compose up -d
We can doublecheck the mounted certificates within the container.
## open internal shell of keycloack container
$ sudo docker exec -it keycloak_app /bin/bash
## open directory of certificates
$ cd /etc/x509/https/
$ ll
-rw----r-- 1 root root 3586 Oct 30 14:21 tls.crt
-rw----r-- 1 root root 1708 Oct 30 14:20 tls.key
Considerung the setup from the docker-compose.yml, keycloak is now available at https://sub.example.com:8443