1. Get public IP address of server

curl ifconfig.me
8.8.8.8

2. Setup a DNS entry that points to that server

2.1. Check DNS name

dig @8.8.8.8 test.javilegido.com +short
8.8.8.8

3. Make sure ports TCP 80 and 443 are open

WARNING: if behind LAN router remember to setup NAT

4. Generate certificate

mkdir etc_letsencrypt
docker run -it \
  --rm \
  --name certbot \
  -v `pwd`/etc_letsencrypt:/etc/letsencrypt \
  -p 80:80 \
  certbot/certbot certonly

1
javi@example.com
Y
N
test.javilegido.com

Requesting a certificate for test.javilegido.com
Successfully received certificate.
Certificate is saved at: /etc/letsencrypt/live/test.javilegido.com/fullchain.pem
Key is saved at:         /etc/letsencrypt/live/test.javilegido.com/privkey.pem
This certificate expires on 2022-08-24.
These files will be updated when the certificate renews.

NEXT STEPS:
- The certificate will need to be renewed before it expires. Certbot can automatically renew the certificate in the background, but you may need to take steps to enable that functionality. See https://certbot.org/renewal-setup for instructions.

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
If you like Certbot, please consider supporting our work by:
 * Donating to ISRG / Let's Encrypt:   https://letsencrypt.org/donate
 * Donating to EFF:                    https://eff.org/donate-le
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

5.

tree

etc_letsencrypt/
├── accounts
│   └── acme-v02.api.letsencrypt.org
│       └── directory
│           └── 77fcea9a20707993ed3e5d65f5960a8f
│               ├── meta.json
│               ├── private_key.json
│               └── regr.json
├── archive
│   └── test.javilegido.com
│       ├── cert1.pem
│       ├── chain1.pem
│       ├── fullchain1.pem
│       └── privkey1.pem
├── csr
│   └── 0000_csr-certbot.pem
├── keys
│   └── 0000_key-certbot.pem
├── live
│   ├── README
│   └── test.javilegido.com
│       ├── cert.pem -> ../../archive/test.javilegido.com/cert1.pem
│       ├── chain.pem -> ../../archive/test.javilegido.com/chain1.pem
│       ├── fullchain.pem -> ../../archive/test.javilegido.com/fullchain1.pem
│       ├── privkey.pem -> ../../archive/test.javilegido.com/privkey1.pem
│       └── README
├── renewal
│   └── test.javilegido.com.conf
└── renewal-hooks
    ├── deploy
    ├── post
    └── pre

	certbot

fullchain.pem	=>	certificate
privkey.pem	=>	key
chain.pem	=>	CA public certificate

acme.json

    "Certificates": [
      {
        "domain": {
          "main": "ranura.d.kedu.coop"
        },
        "certificate": "CONTENT_OF_fullchain.pem",
        "key": "CONTENT_OF_privkey.pem",
        "Store": "default"
      },

6. Deploy traefik with one example

https://doc.traefik.io/traefik/user-guides/docker-compose/acme-tls/

6.1.

vim docker-compose.yml

Adjust:

--certificatesresolvers.myresolver.acme.email
traefik.http.routers.whoami.rule

NOTE: the challenge is listening in port 8080, so don't change it

version: "3.3"

services:

  traefik:
    image: "traefik:v2.7"
    container_name: "traefik"
    command:
      - "--log.level=DEBUG"
      - "--api.insecure=true"
      - "--providers.docker=true"
      - "--providers.docker.exposedbydefault=false"
      - "--entrypoints.websecure.address=:443"
      - "--certificatesresolvers.myresolver.acme.tlschallenge=true"
      #- "--certificatesresolvers.myresolver.acme.caserver=https://acme-staging-v02.api.letsencrypt.org/directory"
      - "--certificatesresolvers.myresolver.acme.email=javi@example.com"
      - "--certificatesresolvers.myresolver.acme.storage=/letsencrypt/acme.json"
    ports:
      - "443:443"
      - "8080:8080"
    volumes:
      - "./letsencrypt:/letsencrypt"
      - "/var/run/docker.sock:/var/run/docker.sock:ro"

  whoami:
    image: "traefik/whoami"
    container_name: "simple-service"
    labels:
      - "traefik.enable=true"
      - "traefik.http.routers.whoami.rule=Host(`test.javilegido.com`)"
      - "traefik.http.routers.whoami.entrypoints=websecure"
      - "traefik.http.routers.whoami.tls.certresolver=myresolver"

6.2. Start

docker-compose up -d

docker logs -f traefik

...
time="2022-06-03T18:15:00Z" level=debug msg="Certificates obtained for domains [test.javilegido.com]" providerName=myresolver.acme routerName=whoami@docker rule="Host(`test.javilegido.com`)" ACME CA="https://acme-v02.api.letsencrypt.org/directory"
time="2022-06-03T18:15:00Z" level=debug msg="Configuration received: {\"http\":{},\"tcp\":{},\"udp\":{},\"tls\":{}}" providerName=myresolver.acme
...

6.3.

(From another host)

wget https://test.javilegido.com

6.4. Stop

sudo docker-compose down 

6.5. Backup

sudo cp letsencrypt/acme.json ./acme.json.bak

7. Replace certs

7.1. Transform certbot certificates in strings

sudo chown -R `whoami`:`whoami` etc_letsencrypt*

_IN=etc_letsencrypt/live/test.javilegido.com/fullchain.pem
_OUT=traefik_certificate
cat $_IN | base64 | tr '\n' ' ' | sed --expression='s/\ //g' > $_OUT

_IN=etc_letsencrypt/live/test.javilegido.com/privkey.pem
_OUT=traefik_key
cat $_IN | base64 | tr '\n' ' ' | sed --expression='s/\ //g' > $_OUT

7.2. Edit:

sudo vim letsencrypt/acme.json 

And replace:

certificate:	Content of file 'traefik_certificate'
key:		Content of file 'traefik_key'

WARNING: both files content differ, “letsencrypt/acme.json” and “acme.json.bak”

8. Test

8.1. Take MD5 of acme.json

sudo md5sum letsencrypt/acme.json 

ec151c804d1776d898b62b1b30691aeb  letsencrypt/acme.json

8.2. Make file “acme.json” readonly

vim docker-compose.yml

And leave change only below line:

      #- "./letsencrypt:/letsencrypt"
      - "./letsencrypt:/letsencrypt:ro"

8.3. Recreate

sudo docker-compose up -d --force-recreate

8.4. Check MD5 of the file:

sudo md5sum letsencrypt/acme.json

ec151c804d1776d898b62b1b30691aeb  letsencrypt/acme.json

Should be the same than step 8.1.

8.5. Test

wget https://test.javilegido.com