Server's internet intermitent

[Jeremyy44]

Hi,

So recently I have been getting some problems with my server's internet.
So my server is on Ubuntu Server 20.04 and whats been happening is that my internet will be fine and working for a while like for exemple it has been working fine for the past week but all of a suden with no good reason or me doing anything it stops. Im noticing it stop since im using Healthcheck.io to monitor my cron jobs and on of them is updating my subdomain wan ip so it needs internet acces to work and when it dosnt I get notifies. The cron job works every hour.
Im using NetworkManager to manage my ip adresse since im using Cockpit as a web GUI to manage my server.
Lan acces is working perfectly fine. Even the DNS server running on it works fine and my devices that only use my servers ip has their dns can connect to the internet. Using PiHole as a DNS server but not as a DHCP server.
Plex also works for outside uses like if im on LTE I can connect and watch anything fine.
I can even have a ssh session work on LTE using my wan ip but my server cannot download any packages, update, run a speedtest.
Pinging 8.8.8.8 also works

This the result of ifconfig

enp9s0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet 192.168.2.10  netmask 255.255.255.0  broadcast 192.168.2.255
        inet6 fe80::e26e:da2f:7003:6cab  prefixlen 64  scopeid 0x20<link>
        ether b4:2e:99:9a:ed:3f  txqueuelen 1000  (Ethernet)
        RX packets 3219472  bytes 997293081 (997.2 MB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 2562698  bytes 5032040808 (5.0 GB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0
        device interrupt 60  base 0x1000

 

[jj9987]

Since you don't mention whether it is a homelab server or a rented one (what parts of the server and network do you control), I'm gonna give quite a general answer.

 

Start with basic connectivity debugging when it loses connection. Test your DNS, test pinging the gateway as well as a public host (like 1.1.1.1 or 8.8.8.8), run traceroutes, test ICMP and TCP/UDP traffic. Are other devices/servers/clients affected? When and how does it recover? Try to find patterns.

[Ubuntu is love]

On 11/1/2021 at 3:46 PM, Jeremyy44 said:

week but all of a suden with no good reason or me doing anything it stops.

Sounds like it creates a network loop, can you post the full netplan or interfaces file

[Jeremyy44]

On 11/4/2021 at 6:31 PM, Ubuntu is love said:

Sounds like it creates a network loop, can you post the full netplan or interfaces file

Hi 

Sry for the late response.

I dont use networkd so no netplan config file is being use. Im using NetworkManager instead and I will post them if that can be of any help.

enp9s0-04111eca-7087-4cd5-8e77-352c6c21e726.nmconnection enp9s0.nmconnection

[Jeremyy44]

On 11/1/2021 at 10:53 AM, jj9987 said:

Since you don't mention whether it is a homelab server or a rented one (what parts of the server and network do you control), I'm gonna give quite a general answer.

 

Start with basic connectivity debugging when it loses connection. Test your DNS, test pinging the gateway as well as a public host (like 1.1.1.1 or 8.8.8.8), run traceroutes, test ICMP and TCP/UDP traffic. Are other devices/servers/clients affected? When and how does it recover? Try to find patterns.

Hi sry for the late response.

When loosing connection I have tried pinging 8.8.8.8 and 1.1.1.1 and I always get a response.

No none of my other are affected even the one connected to my dns server running on my server. They still have perfectly good working internet acces.

It recovers randomly but always seems to happen around every 12h I have attached a pic of my heatlcheck.io logs.

I will also try the tools you recomended once the problem reapears.

[Ubuntu is love]

On 11/10/2021 at 1:41 AM, Jeremyy44 said:

Hi 

Sry for the late response.

I dont use networkd so no netplan config file is being use. Im using NetworkManager instead and I will post them if that can be of any help.

enp9s0-04111eca-7087-4cd5-8e77-352c6c21e726.nmconnection 441 B · 0 downloads enp9s0.nmconnection 360 B · 0 downloads

There files are correctly set up, but like @jj9987 said: Could you try a trace route to see if there happens something weird.

[Jeremyy44]

8 hours ago, Ubuntu is love said:

There files are correctly set up, but like @jj9987 said: Could you try a trace route to see if there happens something weird.

Well when running 

traceroute6 -i enp9s0 google.com

I get 

traceroute6: google.com: Name or service not known

So idk if im doing something wrong or its just caused by not having internet acces but thats what I get.

[Ubuntu is love]

23 minutes ago, Jeremyy44 said:

Well when running 

traceroute6 -i enp9s0 google.com

I get 

traceroute6: google.com: Name or service not known

So idk if im doing something wrong or its just caused by not having internet acces but thats what I get.

It's tracing IPv6... is that supposed to?

[Jeremyy44]

5 minutes ago, Ubuntu is love said:

It's tracing IPv6... is that supposed to?

No its just the package that was installed by default.

I rebooted which like always brings back my internet temporarily so I could install traceroute.

This is the result I get when running the same command but now with traceroute instead of *6

traceroute to google.com (172.217.13.142), 30 hops max, 60 byte packets
 1  192.168.2.1 (192.168.2.1)  0.207 ms  0.293 ms  0.262 ms
 2  10.11.16.25 (10.11.16.25)  1.774 ms  2.287 ms  2.986 ms
 3  * * *
 4  tcore4-montreal02_44.net.bell.ca (64.230.36.102)  8.455 ms  8.431 ms  8.409 ms
 5  cr02-mtrlpq02ho6_bundle-ether1.net.bell.ca (142.124.127.251)  5.692 ms  5.663 ms  7.878 ms
 6  bx2-montrealgz_et-0-0-11.net.bell.ca (64.230.33.167)  5.255 ms  4.266 ms  4.337 ms
 7  google_bx2-montrealgz.net.bell.ca (184.150.180.17)  4.505 ms  4.409 ms  4.502 ms
 8  108.170.251.49 (108.170.251.49)  4.967 ms  5.060 ms 108.170.251.1 (108.170.251.1)  4.835 ms
 9  108.170.231.55 (108.170.231.55)  5.895 ms  5.956 ms  6.134 ms
10  yul02s05-in-f14.1e100.net (172.217.13.142)  5.152 ms  5.138 ms  5.235 ms

Mind you right now after the reboot my server's internet is fine so ill rerun it once my server's internet goes down again.

[Jeremyy44]

Was finnaly able to be logged in my server when having my internet problems.

This is the ouput of traceroute

google.com: Name or service not known
Cannot handle "host" cmdline arg `google.com' on position 1 (argc 3)