Miscellaneous first checks

• I checked that all ports are open and not blocked by my ISP / hosting provider.
• I know that SSL errors are likely the result of a wrong setup on the user side and not caused by DMS itself. I'm confident my setup is correct.

Affected Component(s)

mailserver does not use renewed let's encrypt certificate

What happened and when does this occur?

I'm using traefik v2 to get and renew certificates. The traefik json which holds the certificates has been mounted as volume into the mailserver docker container. When the certificate gets renewed by traefik (~4 weeks before expiry), the mailserver does not recognise this certificate and keeps using the old one. 

I checked certificate with https://www.checktls.com/TestReceiver and it still shows the old one. Opening the Website that uses the same hostname and certificate, it shows the renewed one. 

When I do a restart of the docker container, the new certificate is recognized and from there on used.

What did you expect to happen?

docker mailserver should recognise the updated / renewed certificate (by traefik2) without restarting the container.

How do we replicate the issue?

1. Setup traefik2, nginx webserver and docker mailserver as described in the docu
2. wait until let's encrypt certificate get's renewed by traefik2
3. check that mailserver does not pick renewed certificate
...

DMS version

v10.1.2

How much RAM is available to DMS explicitly?

more than 4GB

How many CPU cores are available?

less than 4 Cores

Is DMS running in a virtualized environment?

... a virtual private server (VPS) (with virtual CPU cores)

What operating system is DMS running on?

Linux

What instruction set architecture is DMS running on?

x86_64 / AMD64

I/O - Persistent memory

docker volume mount ext4

What container orchestration tool are you using?

Docker Compose

Docker version

No response

Docker Compose version

docker-compose version 1.28.5

The output of uname -a

Linux 4.19.0-17-amd64 #1 SMP Debian 4.19.194-3 (2021-07-18) x86_64 GNU/Linux

Important environment variables

Mount point within my docker-compose file: 

      - /data/acme/:/etc/letsencrypt/

I tried 

      - /data/acme/acme.json:/etc/letsencrypt/acme.json:ro

last time but same result.

Relevant log output

No response

Other relevant information

No response

What level of experience do you have with Docker and mail servers?

Trust me, I'm a (computer) engineer! [expert]

Code of conduct

• I have read this project's Code of Conduct and I agree
• I have read the README and the documentation and I searched the issue tracker but could not find a solution

Improvements to this form?

No response