[WSL2/Ubuntu/Debian/Kali] Network not configured

[ericct]

Windows build number: version 2004 Build 19041.264

I've removed all WSL/WSL2 components and Docker before installing only WSL/WSL2. I have the same behaviour on 4 distributions (Ubuntu 18.04/20.04, Debian 10, Kali Linux 2020.1).

All coming lines are from Ubuntu 20.04.

When started, I cannot get any connection. eth0 interface is down and not configured:

ip addr show eth0
4: eth0: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN group default qlen 1000
    link/ether 00:15:5d:3c:76:f7 brd ff:ff:ff:ff:ff:ff

Using ipconfig from Windows gives me information about needed network configuration:

Ethernet adapter vEthernet (WSL):

   Connection-specific DNS Suffix  . :
   Link-local IPv6 Address . . . . . : fe80::a0cf:c53c:da4:86ef%53
   IPv4 Address. . . . . . . . . . . : 172.31.208.1
   Subnet Mask . . . . . . . . . . . : 255.255.240.0
   Default Gateway . . . . . . . . . :

I then manually configure eth0 and add a default route:

sudo ip address add 172.31.208.10/20 broadcast 172.31.223.255 dev eth0
sudo ip route add default via 172.31.208.1

Now the interface:

ip addr show eth0
4: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP group default qlen 1000
    link/ether 00:15:5d:3c:76:f7 brd ff:ff:ff:ff:ff:ff
    inet 172.31.208.10/20 brd 172.31.223.255 scope global eth0
       valid_lft forever preferred_lft forever
    inet6 fe80::215:5dff:fe3c:76f7/64 scope link
       valid_lft forever preferred_lft forever

and the route:

ip route
default via 172.31.208.1 dev eth0
172.31.208.0/20 dev eth0 proto kernel scope link src 172.31.208.10

are correct (network connections are working).

What's not working: network is not fully configured
Expected behaviour: have inet fully configured without manual intervention. Also, the network settings change at each reboot, raising the need for this operation after each reboot.

[betancour]

Hello Fellow Devs 😊

I had an error using WSL2 and Ubuntu 20.04
Seems like the /etc/resolv.conf generates an incorrect nameserver
adjusting this nameserver manually my connection start to working again.

I've tried to disable the auto-generation of this nameserver adjusting the /etc/wsl.conf
with:

[network]
generateResolvConf = false

this creates a linked file with .../run/resolvconf/resolv.conf that don't allows me to create a fixed one.

please let me know if you have any patch or remedy to this error.

Best regards.

[skippednote]

@betancour I set my DNS to the one being used on the host but that didn't help. I've tried solutions on the other issues and none of it has worked so far.

[betancour]

@betancour I set my DNS to the one being used on the host but that didn't help. I've tried solutions on the other issues and none of it has worked so far.

Hi skippednote
Regarding your message
Did you use your router IP as the nameserver?

[skippednote]

@betancour By default it points to 172.20.32.1 which is Ethernet (WSL).
I've tried changing it to 8.8.8.8 as well but that didn't help either.

[betancour]

@betancour By default it points to 172.20.32.1 which is Ethernet (WSL).
I've tried changing it to 8.8.8.8 as well but that didn't help either.

Hi Again @skippednote

I've tried using Google DNS unsuccessfully.

The way that works is when I use my router ip as nameserver
Example:

 betancour  Inspiron-5570  mnt  d  Dev  $  sudo apt-get update
[sudo] password for betancour:
Err:1 https://deb.nodesource.com/node_12.x focal InRelease
  Temporary failure resolving 'deb.nodesource.com'
Err:2 http://archive.ubuntu.com/ubuntu focal InRelease
  Temporary failure resolving 'archive.ubuntu.com'
Err:3 http://security.ubuntu.com/ubuntu focal-security InRelease
  Temporary failure resolving 'security.ubuntu.com'
Err:4 https://dl.yarnpkg.com/debian stable InRelease
  Temporary failure resolving 'dl.yarnpkg.com'
Get:5 http://archive.ubuntu.com/ubuntu focal-updates InRelease [107 kB]
Get:6 http://archive.ubuntu.com/ubuntu focal-backports InRelease [98.3 kB]
Fetched 205 kB in 39s (5261 B/s)
Reading package lists... Done
W: Failed to fetch http://archive.ubuntu.com/ubuntu/dists/focal/InRelease  Temporary failure resolving 'archive.ubuntu.com'
W: Failed to fetch http://security.ubuntu.com/ubuntu/dists/focal-security/InRelease  Temporary failure resolving 'security.ubuntu.com'
W: Failed to fetch https://deb.nodesource.com/node_12.x/dists/focal/InRelease  Temporary failure resolving 'deb.nodesource.com'
W: Failed to fetch https://dl.yarnpkg.com/debian/dists/stable/InRelease  Temporary failure resolving 'dl.yarnpkg.com'
W: Some index files failed to download. They have been ignored, or old ones used instead.
 betancour  Inspiron-5570  mnt  d  Dev  $  echo 'nameserver 192.168.1.1' >> /etc/resolv.conf
 betancour  Inspiron-5570  mnt  d  Dev  $  sudo apt-get update
Get:1 http://security.ubuntu.com/ubuntu focal-security InRelease [107 kB]
Hit:2 http://archive.ubuntu.com/ubuntu focal InRelease
Get:3 http://archive.ubuntu.com/ubuntu focal-updates InRelease [107 kB]
Hit:4 https://dl.yarnpkg.com/debian stable InRelease
Hit:5 https://deb.nodesource.com/node_12.x focal InRelease
Get:6 http://archive.ubuntu.com/ubuntu focal-backports InRelease [98.3 kB]
Fetched 312 kB in 18s (17.8 kB/s)
Reading package lists... Done

[skippednote]

@betancour I'm seeing a similar output. What DNS address is working for you?

[betancour]

Hi @skippednote as you can see I am using the 192.168.1.1

[skippednote]

@betancour This doesn't work for me. Only thing that work is reverting to WSL1

[ericct]

There are two different things here:

• one is to have a network route (initial topic), which sometimes apprently is not set (initial topic here)
• another one is indeed name resolution

Default is to rely on the host machine for name resolution. /etc/resolv.conf is dynamically generated when WSL2 kernel starts. One can of course set another DNS IP.

But, there may also be a third problem with the firewall on the host, blocking communication for WSL2.

At the end, apt update problem can have multiple reasons.

[skippednote]

@ericct I don't have a VPN or Antivirus installed. I have tried with Windows Defender Firewall disabld.

[skippednote]

@betancour @ericct For me it was an issue with the ISP who had disabled post routing. After enabling it internet is working fine in WSL2.

[tokiedokie]

same here

eth0 is down every after reboot
but i configure eth0 up, eth0 can't ip addr
when i configure ip addr and route, network works fine

[ericct]

same here

eth0 is down every after reboot
but i configure eth0 up, eth0 can't ip addr
when i configure ip addr and route, network works fine

Yes, this is the same case. I'm not alone!

It's really that the network is not fully configured, the other cases are other issues.

So, does anyone have a solution for this uncomplete network configuration (inside WSL2)?

[tokiedokie]

clean install windows works for me.

[betancour]

clean install windows works for me.

Anotherway is deleting the account and log again with your account to set default parameters. thanks so much.