[not solved] I think I messed something up in the router settings but cannot understand what... now I have no internet connection

Hello! I (tried, at least) converted an old laptop to a Debian home server, and I was trying to set up duckdns.org and to enable port forwarding on my router. internet connection was working, I installed packages, docker, immich, etc, and then suddenly (I don’t know exactly when) it refuses to connect to the internet. It does connect to local addresses (I can ssh into it) but ping google.com and any other internet-involving command fail. I had set up a rule on the router to forward port 80 to the device’s port 80, but I then removed the rule and it still does not connect to the internet. I rebooted the router but nothing changed. Any idea what could be? the router is a Vodafone router.

https://lemmy.kde.social/pictrs/image/12682af4-71fe-4f72-bd99-82e613fbf507.png

I changed the hostname to debianserver but on the router it is still written debian. Also, it’s the only device with unknown ipv6

thanks in advance!

EDIT: I rebooted again the server, and now ipv6 is not unknown anymore, and the hostname is correct. however, it still does not connect to the internet

https://lemmy.kde.social/pictrs/image/b93cd90b-46ba-43d3-89e3-a5d02c0f1e07.png

EDIT 2:

only one device (debianserver) has this problem, other devices work as before

EDIT 3:

I don’t know if it’s useful or not, but if I boot a live debian USB in the server internet works

SOLUTION: aaaaand no it does not work, after restarting docker it seems to work because all the brodges are yet to be created and it takes some time, after like 30 seconds it does not work as before :(

  • edit the file /lib/systemd/system/docker.service
  • append the flag –bip=192.168.3.1/24 to ExecStart=…
  • systemctl daemon-reload
  • systemctl restart docker

docker was the fucker that messed everything up and made me lose a few hours!

EDIT 4:

it seems that ip route flush 0/0 restores the internet connectivity until reboot… I don’t know what does this means but can be a temporary workaround I guess? I really have no idea how to solve this

Aurix,

Go to the outer status page. The router should display whether it has an internet connection to your provider. If no, then your router/modem has no credentials or another issue preventing access.

If it shows as working, then you can narrow it down to incorrect DNS and IP routing. Perhaps dynamic IP allocation is set to off or another configuration error or bug, in which case you might need to reset all the router settings. Then, is it only broken for a single end device?

tubbadu,

thanks for the reply! Sorry it isn’t very clear from the post, but yes only one device (debianserver) has this problem (no internet connection, but yes local network connection), all other devices works as before. I’ll update the original post to clarify this

Petter1,

Is there a reset button somewhere on the router? Most of them have something like this in order to reset them to factory settings. If not, google for your device name and factory reset, maybe it’s something like „press button while turning on“ etc. I’d try something like that

tubbadu,

Yes there is in the web UI a factory reset button, but I’d rather not do this because it has some settings by other people

mozz,
@mozz@mbin.grits.dev avatar

Does ping 8.8.8.8 work? (To check if it's DNS)

What's ip route show say? (Just to try to narrow down whether it's an issue with the server's config or the router's)

What's traceroute 8.8.8.8 display?

tubbadu,

thanks for the answer!

ping 8.8.8.8 fails, and I don’t have traceroute installed (and no internet to install it)


<span style="color:#323232;">tubbadu@debianserver:~$ ip route show
</span><span style="color:#323232;">0.0.0.0 dev veth3492bf7 scope link
</span><span style="color:#323232;">0.0.0.0 dev vethc1bf668 scope link
</span><span style="color:#323232;">0.0.0.0 dev vethb41fd7e scope link
</span><span style="color:#323232;">0.0.0.0 dev veth2e39932 scope link
</span><span style="color:#323232;">0.0.0.0 dev veth68451d9 scope link
</span><span style="color:#323232;">default dev veth3492bf7 scope link
</span><span style="color:#323232;">default dev vethc1bf668 scope link
</span><span style="color:#323232;">default dev vethb41fd7e scope link
</span><span style="color:#323232;">default via 192.168.1.1 dev enp1s0
</span><span style="color:#323232;">169.254.0.0/16 dev veth68451d9 proto kernel scope link src 169.254.210.75
</span><span style="color:#323232;">169.254.0.0/16 dev veth2e39932 proto kernel scope link src 169.254.242.12
</span><span style="color:#323232;">169.254.0.0/16 dev vethb41fd7e proto kernel scope link src 169.254.185.90
</span><span style="color:#323232;">169.254.0.0/16 dev vethc1bf668 proto kernel scope link src 169.254.225.22
</span><span style="color:#323232;">169.254.0.0/16 dev veth3492bf7 proto kernel scope link src 169.254.123.220
</span><span style="color:#323232;">172.17.0.0/16 dev docker0 proto kernel scope link src 172.17.0.1 linkdown
</span><span style="color:#323232;">172.18.0.0/16 dev br-56cf32fc7cde proto kernel scope link src 172.18.0.1
</span><span style="color:#323232;">192.168.1.0/24 dev enp1s0 proto kernel scope link src 192.168.1.9
</span><span style="color:#323232;">192.168.1.1 dev enp1s0 scope link
</span>
0v0,

Try removing all the superfluous default routes.

mozz, (edited )
@mozz@mbin.grits.dev avatar

This is kind of a nutty network config. It looks like docker is setting up extra default routes, which I could easily see fouling everything up. As a first experiment (warning, this may ruin your networking until the next reboot):

ip route flush 0/0
ip route add default via 192.168.1.1 dev enp1s0

... and see if that makes things work (start with ping 192.168.1.1 and ping 8.8.8.8). If that solves the problem, then I think something about your docker config is adding stuff to your networking that's causing the problem; maybe remove/disable docker completely and then re-add docker things one at a time to see where the problem comes in.

tubbadu,

okay, I thought to have solved the problem but I was wrong, here I go again. When I docker compose up -d the immich server (the only one I have installed) all those routes are created, and apparently some of them conflicts with something else and now my host has no internet connection. however it seems that ip route flush 0/0 solves the problem until the reboot, which is strange. the other command returns RTNETLINK answers: File exists

  • All
  • Subscribed
  • Moderated
  • Favorites
  • •
  • linux@lemmy.ml
  • localhost
  • All magazines
    •
    Loading…
    Loading the web debug toolbar…
    Attempt #