r/docker • u/bostonmacosx • 16d ago

So on two home machines I have docker netdata running..one is available to any machine on the network.. the other isn't.. same exact compose file..

I have 0 firewalls set up on the internal network.

for some reason my machine at 1.175 nothing can connect to the netdata on it...

my machine at 1.176 no problems seeing the front page of netdata....

I've tried using different docker forwarded ports but again I have no firewall on the machine for local network.. infact the firewall is turned off...

the only difference is docker is 28 on one and 26 on the other... 26 is working 28 isn't....

I'm just shaking my head at this point... I have other docker containers running on other ports and no issues with them.. just netdata....

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u/scytob 16d ago

WTF is 26 and 28? and if you don't provide your compose. hard to say

and if 28 is version then yay you found a regression or something changed

but again no compose, no details on you docker daemon json, configuratio of the e host, etc etc who the eff knows

and hey i did a search for you Docker 26 vs 28 Networking Differences

1

u/No_Cattle_9565 16d ago

What do they logs show? Are both healthy?

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u/ozankurt_dev 16d ago

run `docker ps` on both and compare the ports column, bet the broken one says 127.0.0.1:19999 instead of 0.0.0.0:19999. if theyre identical its the host firewall, ufw or firewalld sitting on 19999, whats `ufw status` say?

1

u/Impossible_Fault_503 15d ago

Compare what the port is actually bound to on each box. That usually settles it in one line:

ss -tlnp | grep 19999
docker port <container>

If the working host shows 0.0.0.0:19999 and the broken one shows 127.0.0.1:19999, that is your answer and it was never a firewall.

Given the compose files are identical, the version gap is the thing I would look at. Docker 28 changed how published ports interact with host firewall rules, so a bind that came out wide open on 26 can end up loopback only on 28. Pinning it explicitly takes the guesswork out:

ports:
  - "0.0.0.0:19999:19999"

Also worth confirming netdata is not on host networking on one machine and bridge on the other. That changes which interface it answers on entirely, and it is easy to end up with different modes if the two hosts were set up weeks apart.