I can ping google.com but nothing else?

[dj5000]

Something got messed up with my network setting after I defined a static IP. it took me a while to make it working again but now there some weird symptoms. One of those is that can't resolve dns anymore. I can ping google.com with no problem but pinging microsoft.com, godaddy.com or even 8.8.8.8 gets me ping: connect: Network is unreachable


The machine is an I7, 32Gb ram, running Ubuntu server 20.04, mostly headless. using ssh.


Other devices on my network doesn't have the problem.

$ ifconfig

docker0: flags=4099<UP,BROADCAST,MULTICAST> mtu 1500

inet 172.17.0.1 netmask 255.255.0.0 broadcast 172.17.255.255

ether 02:42:22:f6:ee:c8 txqueuelen 0 (Ethernet)

RX packets 0 bytes 0 (0.0 B)

RX errors 0 dropped 0 overruns 0 frame 0

TX packets 0 bytes 0 (0.0 B)

TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0

eno1: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500

inet 192.168.1.101 netmask 255.255.255.0 broadcast 192.168.1.255

inet6 2a02:14c:805f:ffc5:1ac0:4dff:fe41:3e93 prefixlen 64 scopeid 0x0<global>

inet6 fe80::1ac0:4dff:fe41:3e93 prefixlen 64 scopeid 0x20<link>

ether 18:c0:4d:41:3e:93 txqueuelen 1000 (Ethernet)

RX packets 331527 bytes 83760648 (83.7 MB)

RX errors 0 dropped 0 overruns 0 frame 0

TX packets 182973 bytes 52213897 (52.2 MB)

TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0

device interrupt 16 memory 0x53200000-53220000

lo: flags=73<UP,LOOPBACK,RUNNING> mtu 65536

inet 127.0.0.1 netmask 255.0.0.0

inet6 ::1 prefixlen 128 scopeid 0x10<host>

loop txqueuelen 1000 (Local Loopback)

RX packets 209338 bytes 12397801 (12.3 MB)

RX errors 0 dropped 0 overruns 0 frame 0

TX packets 209338 bytes 12397801 (12.3 MB)

TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0

my /etc/resolv.conf keeps getting cleaned up every reboot to this state:

# This file is managed by man:systemd-resolved(8). Do not edit.

#

# This is a dynamic resolv.conf file for connecting local clients to the

# internal DNS stub resolver of systemd-resolved. This file lists all

# configured search domains.

#

# Run "resolvectl status" to see details about the uplink DNS servers

# currently in use.

#

# Third party programs must not access this file directly, but only through the

# symlink at /etc/resolv.conf. To manage man:resolv.conf(5) in a different way,

# replace this symlink by a static file or a different symlink.

#

# See man:systemd-resolved.service(8) for details about the supported modes of

# operation for /etc/resolv.conf.

nameserver 127.0.0.53

options edns0 trust-ad

$ netstat -r

Kernel IP routing table

Destination Gateway Genmask Flags MSS Window irtt Iface

172.17.0.0 0.0.0.0 255.255.0.0 U 0 0 0 docker0

192.168.1.0 0.0.0.0 255.255.255.0 U 0 0 0 eno1

/etc/netplan/00-installer-config.yaml

network:

version: 2

renderer: networkd

ethernets:

eno1:

addresses: ['192.168.1.101/24']

nameservers:

addresses: [8.8.8.8, 8.8.4.4, 192.168.1.1, 212.143.0.1, 194.90.0.1, '2a02:148::1', '2a02:149::>
(yaml formatting is correct in source file)

Any ideas what went wrong and how to fix it?
Please help...


Btw, pinging IP6 addresses does work!

[TheFu]

(yaml formatting is correct in source file)

Prove it. What you've posted above has errors besides wrong indentation. Details matter.

Use code-tags in the post above. Just edit the post. https://ubuntuforums.org/misc.php?do=bbcode#code
All text, commands, and command output should be posted wrapped in 'code tags'.

Please.

I don't use IPv6.
I don't use docker.
I don't use resolvconf or systemd-resolved. If you have a DNS server on your LAN, then you don't want/need these.

Simplify. I suspect that IPv6 is taking priority.
Try this:
$ more /etc/netplan/01-static.yaml

network:
  version: 2
  renderer: networkd
  ethernets:
     eno1:
       addresses:
          - 192.168.1.101/24
       dhcp4: false
       dhcp6: false
       gateway4: 192.168.1.1
       nameservers:
         addresses: [ 8.8.8.8,8.8.4.4 ]

to get started.
That's the shortest netplan for a static IP that I know works. Notice the indentation is all spaces (never tabs) and that there aren't any spaces between nameservers.

Sorry, I didn't post this earlier. I was on a different machine with a terrible keyboard.

[SeijiSensei]

$ netstat -r
Kernel IP routing table
Destination Gateway Genmask Flags MSS Window irtt Iface
172.17.0.0 0.0.0.0 255.255.0.0 U 0 0 0 docker0
192.168.1.0 0.0.0.0 255.255.255.0 U 0 0 0 eno1

You don't have a default route to an upstream router. I'm guessing it's some machine with a 192.168.1.something address. Let's call it 192.168.1.1. Then you need

sudo ip route add default via 192.168.1.1

or whatever the correct upstream address may be.

[The Cog]

Without an IPv4 default route, only IPv6 destinations will be reachable. I presume you have working IPv6.
Try

ping google.com

and I expect to see successful pings to an IPv6 destination.
Also to be sure, post the output of

ip -4 route
ip -6 route