Change Citadel Domain

Change the Citadel domain address in docker installation

We will use mail as hostname, mail.example.net as our original domain, and mail.example.com as our new domain; and 203.0.113.1 as our public facing IP address on this page for the citadel server. Replace with your own.

Pre-Install

• Before you start set your DNS to point your domain to the servers IP. How to do that is out of this manuals scope.

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Next we will set some variables, replace with your domain and IP address then execute following in your servers shell.

export CIT_DOMAIN_ORG=mail.example.net
export CIT_DOMAIN_NEW=mail.example.com

Change your /etc/hosts & lighttpd.conf file replace old with new domain

# Replace text in files
sed -i "s|$CIT_DOMAIN_ORG|$CIT_DOMAIN_NEW|g" /etc/hosts
sed -i "s|$CIT_DOMAIN_ORG|$CIT_DOMAIN_NEW|g" /etc/lighttpd/lighttpd.conf

# Check config file
lighttpd -tt -f /etc/lighttpd/lighttpd.conf

If there is an error at this point check your /etc/lighttpd/lighttpd.conf file. Fix the problem and run last command again.

• No error continue

certbot certonly --agree-tos --non-interactive --text --rsa-key-size 4096 \
    --email webmaster@${CIT_DOMAIN_NEW} \
    --webroot --webroot-path /srv/www/lighttpd \
    --domains ${CIT_DOMAIN_NEW}

• No error continue

sv stop lighttpd

• No error continue

cp /etc/letsencrypt/live/${CIT_DOMAIN_NEW}/privkey.pem /usr/local/citadel/keys/citadel.key 
cp /etc/letsencrypt/live/${CIT_DOMAIN_NEW}/fullchain.pem /usr/local/citadel/keys/citadel.cer

• No error continue

docker stop citadel
wait
docker rename citadel citadel.net

• No error continue

docker run -d --restart=unless-stopped --network host \
    --volume=/usr/local/citadel:/citadel-data \
    --volume=/usr/local/webcit/.well-known:/usr/local/webcit/.well-known \
    --volume=/usr/local/webcit/static.local:/usr/local/webcit/static.local \
    --name=citadel citadeldotorg/citadel --http-port=8080 --https-port=8443

• No error continue

sv start lighttpd

• Last we change the certbot post renewal hook

sed -i "s|$CIT_DOMAIN_ORG|$CIT_DOMAIN_NEW|g" /etc/letsencrypt/renewal-hooks/post/citadel.sh

All done check your new setup.
If you have a problem ask questions at Citadel Support

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First Created: 2025-04-04
Last Modified: 2026-04-05 19:35