I am trying to access Kafka installed on WSL from a docker container running on the same Windows 11 Pro box.

I can successfully access the WSL from the host Windows but the network interface visible inside the docker container reports the target IP as unreachable.

So, the setup in more details:

Windows Pro:

ipconfig

Ethernet adapter Ethernet:

   Connection-specific DNS Suffix  . :
   Link-local IPv6 Address . . . . . : fe80::81b0:aa6c:3acb:52fb%7
   IPv4 Address. . . . . . . . . . . : 192.168.56.1
   Subnet Mask . . . . . . . . . . . : 255.255.255.0
   Default Gateway . . . . . . . . . :

Wireless LAN adapter Local Area Connection* 1:

   Media State . . . . . . . . . . . : Media disconnected
   Connection-specific DNS Suffix  . :

Wireless LAN adapter Local Area Connection* 2:

   Media State . . . . . . . . . . . : Media disconnected
   Connection-specific DNS Suffix  . :

Wireless LAN adapter Wi-Fi:

   Connection-specific DNS Suffix  . : dhcp.ucom.am
   Link-local IPv6 Address . . . . . : fe80::40d7:4b84:b264:183f%19
   IPv4 Address. . . . . . . . . . . : 192.168.1.109
   Subnet Mask . . . . . . . . . . . : 255.255.255.0
   Default Gateway . . . . . . . . . : 192.168.1.1

Ethernet adapter Bluetooth Network Connection:

   Media State . . . . . . . . . . . : Media disconnected
   Connection-specific DNS Suffix  . :

Ethernet adapter vEthernet (Default Switch):

   Connection-specific DNS Suffix  . :
   Link-local IPv6 Address . . . . . : fe80::17f5:3dc0:93a3:7e6d%30
   IPv4 Address. . . . . . . . . . . : 172.19.112.1
   Subnet Mask . . . . . . . . . . . : 255.255.240.0
   Default Gateway . . . . . . . . . :

Ethernet adapter vEthernet (WSL (Hyper-V firewall)):

   Connection-specific DNS Suffix  . :
   Link-local IPv6 Address . . . . . : fe80::a5b4:8ccc:77a7:8c75%48
   IPv4 Address. . . . . . . . . . . : 172.27.80.1
   Subnet Mask . . . . . . . . . . . : 255.255.240.0
   Default Gateway . . . . . . . . . :

The interface in question’s IP 172.27.80.1:

Docker Engine: v25.0.3

WSL Ubuntu Linux:

uname: Linux Utopia 5.15.133.1-microsoft-standard-WSL2 #1 SMP Thu Oct 5 21:02:42 UTC 2023 x86_64 x86_64 x86_64 GNU/Linux

ifconfig:

eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet **172.27.88.164**  netmask 255.255.240.0  broadcast 172.27.95.255
        inet6 fe80::215:5dff:feea:c915  prefixlen 64  scopeid 0x20<link>
        ether 00:15:5d:ea:c9:15  txqueuelen 1000  (Ethernet)
        RX packets 546948  bytes 728340481 (728.3 MB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 142803  bytes 10004297 (10.0 MB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

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 118326  bytes 20003490 (20.0 MB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 118326  bytes 20003490 (20.0 MB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

Docker container:

uname: Linux docker-desktop 5.15.133.1-microsoft-standard-WSL2 #1 SMP Thu Oct 5 21:02:42 UTC 2023 x86_64 Linux

docker run: docker run --name=kafka --network=host -it python3.10.14-alpine3.19 sh

ifconfig (cut out other irrelevant interfaces):

...
br-2b3932ab9cca Link encap:Ethernet  HWaddr 02:42:94:44:16:A5
          inet addr:172.27.0.1  Bcast:172.27.255.255  Mask:255.255.0.0
          inet6 addr: fe80::42:94ff:fe44:16a5/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:81 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:0 (0.0 B)  TX bytes:3786 (3.6 KiB)

...
eth0      Link encap:Ethernet  HWaddr 22:7F:BA:C1:AE:F3
          inet addr:192.168.65.3  Bcast:192.168.65.255  Mask:255.255.255.0
          inet6 addr: fe80::207f:baff:fec1:aef3/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:1230322 errors:0 dropped:0 overruns:0 frame:0
          TX packets:1183700 errors:0 dropped:102 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:117289185 (111.8 MiB)  TX bytes:469511171 (447.7 MiB)

lo        Link encap:Local Loopback
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:65536  Metric:1
          RX packets:113 errors:0 dropped:0 overruns:0 frame:0
          TX packets:113 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:10510 (10.2 KiB)  TX bytes:10510 (10.2 KiB)

...

ip route:

default via 192.168.65.1 dev eth0
127.0.0.0/8 dev lo scope host
172.17.0.0/16 dev docker0 scope link  src 172.17.0.1
172.24.0.0/16 dev br-e19898417128 scope link  src 172.24.0.1
172.25.0.0/16 dev br-69c5956ec8b4 scope link  src 172.25.0.1
172.26.0.0/16 dev br-e492384c3d90 scope link  src 172.26.0.1
172.27.0.0/16 dev br-2b3932ab9cca scope link  src 172.27.0.1
192.168.49.0/24 dev br-5e9534f79c66 scope link  src 192.168.49.1
192.168.65.0/24 dev eth0 scope link
192.168.65.1 dev eth0 scope link
192.168.65.7 dev services1 scope link
192.168.176.0/20 dev br-cc0f94b89d47 scope link  src 192.168.176.1
192.168.192.0/20 dev br-f33839247be2 scope link  src 192.168.192.1

I successfully connect to the WSL services from Windows host:

curl 172.27.88.164

<!DOCTYPE html>
<html>
...

ping 172.27.88.164

Pinging 172.27.88.164 with 32 bytes of data:
Reply from 172.27.88.164: bytes=32 time<1ms TTL=64
Reply from 172.27.88.164: bytes=32 time<1ms TTL=64
Reply from 172.27.88.164: bytes=32 time<1ms TTL=64
Reply from 172.27.88.164: bytes=32 time<1ms TTL=64

Anyhow, if a try to access the same IP address from within the docker container, I get this:

# traceroute 172.27.88.164
traceroute to 172.27.88.164 (172.27.88.164), 30 hops max, 46 byte packets
 1  172.27.0.1 (172.27.0.1)  3140.671 ms **!H**  3111.142 ms **!H**  3119.825 ms **!H**

I tried to disable/enable the vEthernet (WSL (Hyper-V firewall)) internet adapter but nothing changes.