Dns resolution not working

[Thundercat]

Hi!
I have a Proxmox server running a few virtual machines. The proxmox server itself can ping destinations such as 8.8.8.8 and google.com
The vm's cant. They can ping 8.8.8.8 but they cant ping google.com. This shouldnt be a problem when looking through my local DNS (Pihole) and my Router isnt detecting any problems.


Ive got my router (Edgerouter 10x) set up with a few Vlans, the proxmox server is on its own Vlan over at 10.10.70.7 and the vm's take ip-adresses within the same scope (after xx.xx.70.7 that is).


I cant for my life understand why the vms's can ping the outside world (and local machines) but cant seem to access a Domain name adress.
This is a new issue and i havent done anything to the proxmox install to cause this, ive added a second dns to the local Vlan (1.1.1.1) as to try and resolve adresses outside of my local DNS but that doesnt seem to help either.


Anyone with an idea as to whats going on?

 

[RajatSharma]

Hi!
I have a Proxmox server running a few virtual machines. The proxmox server itself can ping destinations such as 8.8.8.8 and google.com
The vm's cant. They can ping 8.8.8.8 but they cant ping google.com. This shouldnt be a problem when looking through my local DNS (Pihole) and my Router isnt detecting any problems.


Ive got my router (Edgerouter 10x) set up with a few Vlans, the proxmox server is on its own Vlan over at 10.10.70.7 and the vm's take ip-adresses within the same scope (after xx.xx.70.7 that is).


I cant for my life understand why the vms's can ping the outside world (and local machines) but cant seem to access a Domain name adress.
This is a new issue and i havent done anything to the proxmox install to cause this, ive added a second dns to the local Vlan (1.1.1.1) as to try and resolve adresses outside of my local DNS but that doesnt seem to help either.


Anyone with an idea as to whats going on?

Probably Check your default gateway settings.

Are you talking about the VMs or the LXC Containers?

Please use a network scanner and check if the IP addresses are not conflicting.

I would also work around the VLAN configurations too, just to be sure.

Regards.

 

[Thundercat]

Probably Check your default gateway settings.

Are you talking about the VMs or the LXC Containers?

Please use a network scanner and check if the IP addresses are not conflicting.

I would also work around the VLAN configurations too, just to be sure.

Regards.

Vm's
There are no Ip conflicts, each machine has its own ip and i can ping those individual ip's without error. I can see the dhcp updating with new ip adresses on that Vlan for every new vm i start.

This is the output from one of them:

This is one that CAN resolve dns queries: Could there still be network conflicts? And do you have a tool in mind?

 

[Thundercat]

So aparently i have 1 machine that does resolve properly and two that dont... Sounds like a conflict doesnt it.
Edit, make it 2 machines... Im getting dns errors when the third one starts:

DNSMASQ_WARN

Warning in dnsmasq core:Ignoring query from non-local network

 

[RajatSharma]

Vm's
There are no Ip conflicts, each machine has its own ip and i can ping those individual ip's without error. I can see the dhcp updating with new ip adresses on that Vlan for every new vm i start.

This is the output from one of them:

View attachment 46220 This is one that CAN resolve dns queries: View attachment 46221 Could there still be network conflicts? And do you have a tool in mind?

Which OS are you running on these VMs?

 

[mikeinnyc]

ip a
make sure you see state UP
then check your router and stay there. make the rules simple at first then tighten as you go along

 

[xrobau]

Remove the /etc/resolv.conf symlink and use the public resolvers directly. Whatever is in /etc/resolv.conf is broken (and is using dnsmasq incorrectly according to your logs)

sudo -i
rm -f /etc/resolv.conf
cat > /etc/resolv.conf << EOF
nameserver 1.1.1.1
nameserver 8.8.8.8
options edns0
EOF