Container fails on startup with NameResolutionError on QNAP Container Station 3

[mkieszek]

When starting zoeyvid/npmplus:latest on QNAP Container Station 3 (static IP network), the container crashes during ACME init:

requests.exceptions.ConnectionError: HTTPSConnectionPool(host='acme-v02.api.letsencrypt.org', port=443): Max retries exceeded with url: /directory (Caused by NameResolutionError(...: Failed to resolve 'acme-v02.api.letsencrypt.org' ([Errno -3] Try again)"))

However, when I exec into the container after it starts, curl https://acme-v02.api.letsencrypt.org/directory works fine. If I then manually run entrypoint.sh inside the container, NPMplus starts normally.

Environment:

• Platform: QNAP NAS, Container Station 3
• Network: Qnet static IP

It seems the initial Certbot call runs before DNS is fully ready, even though it works moments later. Running entrypoint.sh manually after container start succeeds.

[Zoey2936]

how does your /etc/resolv.conf inside the container look like?

[mkieszek]

cat /etc/resolv.conf 
# Generated by Docker Engine.
# This file can be edited; Docker Engine will not make further changes once it
# has been modified.

nameserver 127.0.0.11
options ndots:0

# Based on host file: '/etc/resolv.conf' (internal resolver)
# ExtServers: [1.1.1.1 192.168.18.40]
# Overrides: [nameservers]
# Option ndots from: internal

[Zoey2936]

I'm not sure if I can do much here, sounds more like an Issue of QNAPs docker implementation

[mkieszek]

thank you, anyway it is working for me so I don't need anything more.
I appreciate your work, a lot!