Thank you for pointing me out in the right direction.
My mistake was to take for granted a working configuration made by someone else and even reading the web interface doc did not help me to understand the web_endpoint_uri problem.
Removing this variable made it works now.
Here is the final working configuration.
graylog:
image: graylog2/server:latest
container_name: graylog
hostname: graylog
environment:
GRAYLOG_IS_MASTER: “true”
GRAYLOG_PASSWORD_SECRET: somepasswordpepper:)
GRAYLOG_ROOT_PASSWORD_SHA2: whoreallycares?
GRAYLOG_SERVER_JAVA_OPTS: -Xms2g -Xmx4g -XX:NewRatio=1 -XX:MaxMetaspaceSize=256m -server -XX:+ResizeTLAB -XX:+UseConcMarkSweepGC -XX:+CMSConcurrentMTEnabled -XX:+CMSClassUnloadingEnabled -XX:+UseParNewGC -XX:-OmitStackTraceInFastThrow
GRAYLOG_REST_ENABLE_TLS: “true”
GRAYLOG_WEB_ENABLE_TLS: “true”
GRAYLOG_REST_TLS_CERT_FILE: /usr/share/graylog/data/config/ssl/graylog.prod.lan.cert.pem
GRAYLOG_REST_TLS_KEY_FILE: /usr/share/graylog/data/config/ssl/graylog.prod.lan.pkcs8.key.pem
GRAYLOG_WEB_TLS_CERT_FILE: /usr/share/graylog/data/config/ssl/graylog.prod.lan.cert.pem
GRAYLOG_WEB_TLS_KEY_FILE: /usr/share/graylog/data/config/ssl/graylog.prod.lan.pkcs8.key.pem
GRAYLOG_REST_TRANSPORT_URI: https://graylog.prod.lan:9000/api
GRAYLOG_ELASTICSEARCH_HOSTS: http://elasticsearch:9200,http://elasticsearch2:9200
GRAYLOG_MONGODB_URI: mongodb://mongo:27017,mongo2:27017/graylog?replicaSet=graylog
depends_on:
- mongo
- elasticsearch
ports:
- “443:9000”
- “514:514/tcp”
- “514:514/udp”
- “1514/udp:1514/udp”
- “5044:5044/tcp”
- “9000:9000”
- “9350:9350”
- “12200-12300:12200-12300/tcp”
- “12200-12300:12200-12300/udp”
- “12900:12900”
networks:
graylog:
aliases:
- graylog