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Docker container unable to access resources via VPN

Hi all,

I’m running an Ubuntu docker container on my Windows 10 host machine. Both the host and the container have internet connectivity.

I use a remote access VPN (Cisco AnyConnect) to access external resources from my Host machine. I now also want to access them from the docker container. Here is the issue, the host win10 machine can access the resources via the VPN fine BUT the container cannot access SOME of the resources.

My Remote VPN adds the following routes to the Host PC [10.0.0.0/8] and [172.16.0.0/12] these routes are for the external resources accessible over the VPN. Both of the above mentioned subnets are accessible from the windows Host machine. However, only 10.0.0.0/8 is accessible from the ubuntu container, 172.16.0.0/12 is not.

My 1st thought was that the containers IP addressing was conflicting with the VPN resources’ subnet So I created a new docker network which uses [172.32.0.0/16] which falls outside the /12 subnet the VPN adds. But I still can’t access resources belonging to [172.16.0.0/12]. Not sure why as there isn’t any conflict of subnets.

Any idea how I can fix this?

Kind regards