Question about Proxmox and OpenWRT

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nborges

New Member
Jan 11, 2025
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Hello Guys,
i am new on promox and for what i see is exelent, very good... now i have a question... i have a old computer that i install Promox, and have installed 2 VM, for tests now only, before go all in on proxmox...
vms that i install was one with ubuntu desktop and one with OpenWRT, i allready have configured OpenWRT and everthing is running good, have internet and everything, i configure the network card on ubuntu and got ip on server trought DHCP that came from openwrt settings, but have no internet on it... since promox use linux bridge i do not know if i need to do anything more... i have a new subnet configured with a diferent ip of my network, the ubuntu got the ip correctly throught dhcp from openWRT but no internet?? what could be this... allready configured to firewall rules... no more ideas? anyone have some more ideas, thanks
 
Create a bridge, vmbr1
do not attach any network cards
connect your openwrt LAN port and desktop port to it.
openwrt will server dhcp to your desktop and share the internet
leave openwrt wan port on vmbr0 so it can access the internet
 
This is what i have one my openWRT Network Cards
1736681853774.png

On my desktop

1736681926155.png
I am able to get DHCP from WRT but now internet... this is very very strange....
on my WRT server i can ping everything... and have no firewall ativated...


Thanks for you feedback and answer... but is not working...
 
What is the ip range on both sides

run ifconfig on the openwrt

if they are 192.168.1.* on both sides you might have an issue
 
not it's not on the same subnet, the eth1 is my wan eth0 is my lan
1736682391110.png

and this is the ip from DHCP that i got on desktop

1736682610175.png

Thanks one more time for your help
 
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Post ip a from Proxmox host.
Does the Proxmox host have a full internet connection?
 
i have access to everything iallready tried to ping those ips without any problems, that's why i have no more ideas :)
1736686880328.png
 
nborges said:
here the "ip a", and promox host have internet connection without any problem... i

View attachment 80618
Click to expand...
Your Proxmox host is on the WAN side of your OpenWRT (vmbr0), while your VMs are on the LAN size of your OpenWRT (vmbr1). That explains the difference but not why the VMs don't get internet.

I can only assume that it's a OpenWRT configuration issue with routing or DNS. I could not find a reply from you that shows ping 8.8.8.8 and ping google.com and ip r from inside a (Linux) VM, to determine whether it's just a DNS problem or not.
Maybe move your Proxmox from vmbr0 to vmbr1 and run those commands?
 
leesteken said:
Your Proxmox host is on the WAN side of your OpenWRT (vmbr0), while your VMs are on the LAN size of your OpenWRT (vmbr1). That explains the difference but not why the VMs don't get internet.

I can only assume that it's a OpenWRT configuration issue with routing or DNS. I could not find a reply from you that shows ping 8.8.8.8 and ping google.com and ip r from inside a (Linux) VM, to determine whether it's just a DNS problem or not.
Click to expand...
1736688435276.png
leesteken said:
Maybe move your Proxmox from vmbr0 to vmbr1 and run those commands?
Click to expand...

you saying change vmbr1 as wan and vmbr0 as lan?

Thanks again for help everyone...
 
nborges said:
you saying change vmbr1 as wan and vmbr0 as lan?
Click to expand...
No. I'm saying to give the Proxmox host an IP address om vmbr1 (which is your new LAN) instead of vmbr0. However, it might be wise to wait until you fix the LAN problems.

nborges said:
View attachment 80620
Click to expand...
It's clearly not just a DNS issue. The OpenWRT appears to reply with 192.168.10.254 as the gateway but that's the broadcast address and not usable as a normal IP address. Please do not use 192.168.10.254 as the OpenWRT LAN IPv4 address! Have you tried using 192.168.10.1 as the IP for eth0 instead?

EDIT: Turns out I'm wrong about the broadcast address, sorry.
 
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leesteken said:
No. I'm saying to give the Proxmox host an IP address om vmbr1 (which is your new LAN) instead of vmbr0. However, it might be wise to wait until you fix the LAN problems.


It's clearly not just a DNS issue. The OpenWRT appears to reply with 192.168.10.254 as the gateway but that's the broadcast address and not usable as a normal IP address. Please do not use 192.168.10.254 as the OpenWRT LAN IPv4 address! Have you tried using 192.168.10.1 as the IP for eth0 instead?

EDIT: Turns out I'm wrong about the broadcast address, sorry.
Click to expand...
When you said to change the promox ip adress on vmbr1 to vmbr0 of promox, that's what i am going to do after fixing this LAN issue, what i am doing first is put everything work before anything else...

I allready change the configuration from 192.168.10.254 to 192.168.10.1 to test, on desktop allready update the change1736690952201.png
but still no internet...
1736691017553.png
1736691066385.png
Configured this things o OpenWRT, and in my thoughts should be only the configuration that need to be done in OpenWRT....
 
Finally fixed the things... the problem was not in promox but in OpenWRT, i did not activate "Masquerating" without this option internet does not work... thank you everyone to the help that you told me to do... i allready have learned a lot in promox.. configuration... one more time thank you from heart

Kind Regards
Nuno Borges
 
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Maybe you need to tell us more about how your LAN is set up. You have private IP addresses on both sides of your OpenWRT. Is there another router somewhere? There kind of has to be for anything to get out to the Internet.

THAT router is almost certainly doing NAT aka Masquerading, which means it is going to rewrite packets from it's LAN side to be a real IP address for outbound packets. It will track connection state so as to be able to also rewrite the responses. But it can't do that for 192.168.10.xx because those will appear to be just bogus packets.

Assuming that there is another router provided by your ISP operating as I described above, you should enable the Masqerading check-box on the WAN zone of this router. Otherwise you will be sending packets with a source IP of 192.168.10.xx to a router that does not know about that network. So they will get dropped.

ETA: I was writing this while you were writing your last response <g>.
 
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BobhWasatch said:
Maybe you need to tell us more about how your LAN is set up. You have private IP addresses on both sides of your OpenWRT. Is there another router somewhere? There kind of has to be for anything to get out to the Internet.

THAT router is almost certainly doing NAT aka Masquerading, which means it is going to rewrite packets from it's LAN side to be a real IP address for outbound packets. It will track connection state so as to be able to also rewrite the responses. But it can't do that for 192.168.10.xx because those will appear to be just bogus packets.

Assuming that there is another router provided by your ISP operating as I described above, you should enable the Masqerading check-box on the WAN zone of this router. Otherwise you will be sending packets with a source IP of 192.168.10.xx to a router that does not know about that network. So they will get dropped.

ETA: I was writing this while you were writing your last response <g>.
Click to expand...
yes, that was it... my god,,, my head hearts hahahah appreciate one more time your help and everyone too
 
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