Wireguard - VPN works but no longer internet connection after update to 7.9.3

Troubleshooting
1

Hi there,

Internet doesnt work on my smartphone anymore after a recent update to 7.9.3. It seems things broke after I restarted my pi a couple of days later after the update.

I can SSH into my pi with active VPN but then I cannot browse the internet any more. This was working fine in the past.
Any idea? What information do you need to verify the issue?

Wg0.conf

[Interface]
Address = 10.9.0.1/24,fc00:9:0::1/64
PrivateKey = 
ListenPort = 51820

PostUp = sysctl net.ipv4.conf.%i.forwarding=1 net.ipv4.conf.$(ip r l 0/0 | mawk '{print $5;exit}').forwarding=1                                 
PostUp = sysctl net.ipv6.conf.$(ip r l 0/0 | mawk '{print $5;exit}').accept_ra=2
PostUp = sysctl net.ipv6.conf.%i.forwarding=1 net.ipv6.conf.$(ip r l 0/0 | mawk '{print $5;exit}').forwarding=1
PostUp = iptables -A FORWARD -i %i -j ACCEPT; iptables -t nat -A POSTROUTING -o $(ip r l 0/0 | mawk '{print $5;exit}') -j MASQUERADE
PostUp = ip6tables -A FORWARD -i %i -j ACCEPT; ip6tables -t nat -A POSTROUTING -o $(ip r l 0/0 | mawk '{print $5;exit}') -j MASQUERADE
PostDown = iptables -D FORWARD -i %i -j ACCEPT; iptables -t nat -D POSTROUTING -o $(ip r l 0/0 | mawk '{print $5;exit}') -j MASQUERADE
PostDown = ip6tables -D FORWARD -i %i -j ACCEPT; ip6tables -t nat -D POSTROUTING -o $(ip r l 0/0 | mawk '{print $5;exit}') -j MASQUERADE

Many thanks in advance.

2

Can you post the following after the tunnel is up?

iptables-save -c
3 
Root@DietPi:~# iptables-save -c
# Generated by xtables-save v1.8.2 on Thu Dec 23 14:49:39 2021
*filter
:INPUT ACCEPT [0:0]
:FORWARD ACCEPT [0:0]
:OUTPUT ACCEPT [0:0]
[44:3075] -A FORWARD -i wg0 -j ACCEPT
COMMIT
# Completed on Thu Dec 23 14:49:39 2021
# Generated by xtables-save v1.8.2 on Thu Dec 23 14:49:39 2021
*nat
:PREROUTING ACCEPT [0:0]
:INPUT ACCEPT [0:0]
:POSTROUTING ACCEPT [0:0]
:OUTPUT ACCEPT [0:0]
[8197:660800] -A POSTROUTING -o wlan0 -j MASQUERADE
COMMIT
# Completed on Thu Dec 23 14:49:39 2021
4

just for my unterstanding

  • DietPi is Wireguard VPn server
  • your mobile device is connection to the VPN server
  • your are able to access DietPi via SSH wile your mobile device is outside your local network (while connected on VPN)

Question:

  • Are you using any local DNS server like PiHole?
  • are you able to open website https://1.1.1.1/ while connected via VPN?
5

Yes to all your questions.

What doesn’t work is reloading content in apps like LinkedIn or opening https://www.dnsleaktest.com as one example showing something is off but I don’t know what that could be.

6

Do you have set Pihole to listen on all interface, Permit all origins?

7

I always had, yes.

But I have reset/reenabled it again and saved the setting in pihole settings page.

Internet seems to work again now.

Issues solved. Thanks :slight_smile: