Check your gateway
this post was submitted on 01 Apr 2024
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It is set to my router IP
Can you ping 1.1.1.1?
no
What message are you seeing?
Nothing, and it just reports 100% packet loss when I terminate the ping command.
What is the output of ip route?
That looks good. I also have a Proxmox cluster so if you want something to compare too. Maybe try deleting your network settings and then recreating.
In the UI, go to your host -> system -> network and confirm that you have a default gateway set.
I have, and it's correct.
That doesn't match your ip route. And the gateway 10.99.3.1 is not on the CIDR of that bridge.
That image is not mine, it's just for reference by the other user to show me where to look
Damn, apparently I mixed that up when I was looking at it on my phone app.
Sounds like potentially a DNS issue
This is what I'm thinking too, but I don't know how to fix it.
Do you have a nameserver set under System > DNS?
It's pointing to the IP of my Adguard (located on a different machine)
Have you tried setting the nameserver to Google or Cloudflare to see if that works?
i have, it doesn't work. I can ping my Adguard without issues though.
I suppose you have also logged into your Adguard server to verify that it can ping the internet?
In other words, you have successfully pinged Proxmox --> Adguard and Adguard --> Internet?
Yes, adguard has access to internet
Can you dig @9.9.9.9? If so, its certainly DNS. If it's not DNS, perhaps try to check your iptables iptables -L && iptables -t nat -L.
I'm not really sure what to look for, I'm not very experienced in network, but this is the output i get
From the output, you don't have any routing rules for your machine that block outgoing traffic. The dig command confirms that you can talk to servers. 9.9.9.9 is a common DNS Server. Based off of this, it seems like your problem is that your system has a bad DNS configuration (it's always DNS).
Can you parhaps cat /etc/resolv.con? This file normally contains the used DNS servers for Linux systems, unless using special software.
sure
Okay, no external software for DNS management present here. Is that ip a working DNS Server? Is it your server itself perhaps?
192.168.68.210 is my adguard, it's on a different machine. It should be working, all my other devices use it and I can see the traffic going through it. My servers IP is 192.168.68.120, and I can't see traffic from that on my adguard at all. But it can ping my adguard.
Okay, so if that's your actual DNS Server, can you confirm that it works? dig @yourdns debian.org, for example. Afterwards try to use the default DNS of your system dig debian.org. If both works, your DNS config should be fine. Try a curl debian.org -v too.
debian.org is just a random domain for this, use whatever you want. I don't see anything badly configured so far.
as far as i can tell from the output, i think my DNS is working?
Is the host configured with static IP or DHCP? Either way, verify it has the correct DNS config.
Personally I use static for any device that hosts a service.
What happens if you ping Yahoo.com from the console in Proxmox? It should show the DNS server IP it's using for resolution.
It's set to static, I also do that for anything that hosts something.
It won't ping yahoo.com at all, it just reports 100% packet loss.
Edit: just realised that it won't ping my gateway/router either. It's pinging all other devices on my network just fine though.
can you ping 8.8.8.8?
Not dns then. For some reason you can’t reach the default gateway
Nope, same result
If you can't ping your gateway, then you have a problem with your interface configuration.
Do you need it to be on a specific VLAN or something else?
No i haven't split anything in to separate VLANs
This really sounds like a problem with the default route. What’s the output of ip route? That should give us some hints about what’s up.
this is the output of ip route.
192.168.68.1 is my router, 192.168.68.120 is the proxmox host
Cool. That looks right. Have you checked that the bridge is set up properly and that the router doesn’t have anything silly going on for that subnet?
PVE’s network settings are in /etc/network/interfaces and that’s where you can see how the bridge is set up.
It might be beneficial to know more about your network. Is this the only subnet or do you have a bunch of VLANs? Can other devices on the subnet ping outbound? Have you looked at the firewall on PVE?
this is the contents of the interfaces file
I don't have anythiung seperated in to different VLANs, and i only use this single subnet. all other devices can ping outbound without issues.
Acronyms, initialisms, abbreviations, contractions, and other phrases which expand to something larger, that I've seen in this thread:
| Fewer Letters | More Letters |
|---|---|
| DHCP | Dynamic Host Configuration Protocol, automates assignment of IPs when connecting to a network |
| DNS | Domain Name Service/System |
| IP | Internet Protocol |
| PCIe | Peripheral Component Interconnect Express |
[Thread #648 for this sub, first seen 1st Apr 2024, 16:45] [FAQ] [Full list] [Contact] [Source code]
Does it work after a reboot? I vaguely remember having this problem on my old motherboard. Adding a PCIe LAN adapter and switching everything over solved it for me. Now I have a new mobo and it doesn't have any network problems.
Nope, reboot doesn't change anything
Try a traceroute to something like 9.9.9.9 and google's IP. You're able to resolve things ok. So, not DNS. Need to find out where the traffic is going to die.
Also, try a curl https://google.com -vvv. This should give some more info on what is happening to TCP traffic.
this is the output when i run curl httpS://google.com -vvv
