TLS challenge with docker-compose: acme: error presenting token: timeout - docker-compose

Question

I'm running the basic TLS challenge docker example:
version: "3.3"
services:
traefik:
image: "traefik:v2.4"
restart: always
command:
- "--log.level=DEBUG"
- "--api.insecure=true"
- "--providers.docker=true"
- "--providers.docker.exposedbydefault=false"
- "--entrypoints.websecure.address=:443"
- "--certificatesresolvers.mytlschallenge.acme.tlschallenge=true"
#- "--certificatesresolvers.myresolver.acme.caserver=https://acme-staging-v02.api.letsencrypt.org/directory"
- "--certificatesresolvers.mytlschallenge.acme.email=${SSL_EMAIL}"
- "--certificatesresolvers.mytlschallenge.acme.storage=/letsencrypt/acme.json"
ports:
- "443:443"
- "8080:8080"
volumes:
- ${DATA_FOLDER}/letsencrypt:/letsencrypt
- /var/run/docker.sock:/var/run/docker.sock:ro
n8n:
image: mjysci/n8n:latest-rpi
restart: always
ports:
- "127.0.0.1:5678:5678"
labels:
- traefik.enable=true
- traefik.http.routers.n8n.rule=Host(`${SUBDOMAIN}.${DOMAIN_NAME}`)
- traefik.http.routers.n8n.tls=true
- traefik.http.routers.n8n.entrypoints=websecure
- traefik.http.routers.n8n.tls.certresolver=mytlschallenge
- traefik.http.middlewares.n8n.headers.SSLRedirect=true
- traefik.http.middlewares.n8n.headers.STSSeconds=315360000
- traefik.http.middlewares.n8n.headers.browserXSSFilter=true
- traefik.http.middlewares.n8n.headers.contentTypeNosniff=true
- traefik.http.middlewares.n8n.headers.forceSTSHeader=true
- traefik.http.middlewares.n8n.headers.SSLHost=${DOMAIN_NAME}
- traefik.http.middlewares.n8n.headers.STSIncludeSubdomains=true
- traefik.http.middlewares.n8n.headers.STSPreload=true
environment:
- N8N_BASIC_AUTH_ACTIVE=true
- N8N_BASIC_AUTH_USER
- N8N_BASIC_AUTH_PASSWORD
- N8N_HOST=${SUBDOMAIN}.${DOMAIN_NAME}
- N8N_PORT=5678
- N8N_PROTOCOL=https
- NODE_ENV=production
- WEBHOOK_TUNNEL_URL=https://${SUBDOMAIN}.${DOMAIN_NAME}/
volumes:
- /var/run/docker.sock:/var/run/docker.sock
- ${DATA_FOLDER}/.n8n:/home/node/.n8n
But when I'm running it says:
level=error msg="Unable to obtain ACME certificate for domains \"<MY_DOMAIN>\": unable to generate a certificate for the domains [<MY_DOMAIN>]: error: one or more domains had a problem:\n[<MY_DOMAIN>] [<MY_DOMAIN>] acme: error presenting token: timeout 2021-02-01 10:09:04.491784271 +0000 UTC m=+378.657940910\n" providerName=mytlschallenge.acme routerName=n8n#docker rule="Host(`<MY_DOMAIN>`)"
In the browser, the application is available and works well with HTTPS but it says the certificate isn't valid (obviously). What could be wrong here?

Answer 1

i'm having the same problem on some domains.
It looks like its a timeout.
i tried to restart traefik now. same issue again.
ps: add traefik in the title of the thread, you may gain more visibility and answers.
EDIT: I reverted to version 2.3.7 and it works again.
there must be a bug in 2.4 (latest)
i created an issue :
https://github.com/traefik/traefik/issues/7848