[Error] SNX VPN in rootful container: Connection NetworkManager possible?

**Describe the bug**
My university uses SNX VPN to connect to internal resources. The client is quite outdated, but I managed to install it successfully in a rootful distrobox container. It also says that it connected successfully after installing kmod in the container. However, I still can't access internal web pages. The weird thing is: After some time, it started working and I could access internal pages, but after a reboot, it doesn't work again. ip link and ip route show that it is able to do something, but I'm not sure why it isn't connecting.

**To Reproduce**
Create distrobox using this command: `distrobox-create --name Tumbleweed-SNX --image opensuse/distrobox:latest --additional-flags "--cap-add=ALL -v /lib/modules:/lib/modules --privileged" --root`
Install SNX VPN in container
Try to connect to a supported VPN

**Expected behavior**
The connections should work, I should be able to access internal resources

**Logs**
Run the commands with `--verbose` and post the log here as a file upload
Attach also the output of `podman logs` or `docker logs`, possibly with `--latest` flag
podman logs doesn't find the container help?

**Desktop (please complete the following information):**
- Are you using podman, docker or lilipod? podman
- Which version or podman, docker or lilipod? podman version 5.4.0
- Which version of distrobox? distrobox: 1.8.1.2
- Which host distribution? Aeon
- How did you install distrobox? was preinstalled

**Additional context**
Add any other context about the problem here.
ip link and ip route on the host and in the container are identical.
They show:
with VPN:
```
ip link
1: lo: mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
2: wlp1s0: mtu 1500 qdisc noqueue state UP mode DORMANT group default qlen 1000
link/ether 14:ac:60:d8:3f:1f brd ff:ff:ff:ff:ff:ff
altname wlx14ac60d83f1f
15: tunsnx: mtu 1350 qdisc pfifo_fast state UNKNOWN mode DEFAULT group default qlen 100
link/none
```

```
ip route
0.0.0.0 dev tunsnx src 192.168.26.249
default via 192.168.1.10 dev wlp1s0 proto dhcp src 192.168.1.142 metric 600
10.0.4.0/29 dev tunsnx src 192.168.26.249
10.10.10.0/24 dev tunsnx src 192.168.26.249
10.60.0.0/18 dev tunsnx src 192.168.26.249
10.60.64.1 dev tunsnx src 192.168.26.249
10.60.64.3 dev tunsnx src 192.168.26.249
10.61.0.0/27 dev tunsnx src 192.168.26.249
10.61.1.0/24 dev tunsnx src 192.168.26.249
10.61.2.0/24 dev tunsnx src 192.168.26.249
10.61.200.1 dev tunsnx src 192.168.26.249
10.149.0.0/18 dev tunsnx src 192.168.26.249
10.170.1.1 dev tunsnx src 192.168.26.249
10.170.2.1 dev tunsnx src 192.168.26.249
10.170.3.1 dev tunsnx src 192.168.26.249
10.224.0.0/13 dev tunsnx src 192.168.26.249
141.89.221.0/25 dev tunsnx src 192.168.26.249
141.89.224.0/24 dev tunsnx src 192.168.26.249
141.89.225.0/25 dev tunsnx src 192.168.26.249
141.89.225.145 dev tunsnx src 192.168.26.249
141.89.225.160/27 dev tunsnx src 192.168.26.249
141.89.225.192/26 dev tunsnx src 192.168.26.249
141.89.226.1 dev tunsnx src 192.168.26.249
141.89.226.64/27 dev tunsnx src 192.168.26.249
141.89.226.97 dev tunsnx src 192.168.26.249
141.89.226.136/29 dev tunsnx src 192.168.26.249
141.89.226.161 dev tunsnx src 192.168.26.249
141.89.226.192/26 dev tunsnx src 192.168.26.249
172.16.1.0/28 dev tunsnx src 192.168.26.249
172.16.16.0/20 dev tunsnx src 192.168.26.249
172.16.48.1 dev tunsnx src 192.168.26.249
172.16.52.0/22 dev tunsnx src 192.168.26.249
172.16.56.0/22 dev tunsnx src 192.168.26.249
172.16.60.1 dev tunsnx src 192.168.26.249
172.16.60.34 dev tunsnx src 192.168.26.249
172.16.64.0/22 dev tunsnx src 192.168.26.249
172.16.68.1 dev tunsnx src 192.168.26.249
172.16.72.1 dev tunsnx src 192.168.26.249
172.16.254.1 dev tunsnx src 192.168.26.249
172.17.0.0/20 dev tunsnx src 192.168.26.249
172.17.16.0/21 dev tunsnx src 192.168.26.249
172.17.24.0/22 dev tunsnx src 192.168.26.249
172.17.128.0/20 dev tunsnx src 192.168.26.249
172.18.0.0/20 dev tunsnx src 192.168.26.249
172.18.16.0/21 dev tunsnx src 192.168.26.249
172.18.24.0/22 dev tunsnx src 192.168.26.249
172.18.128.0/21 dev tunsnx src 192.168.26.249
172.18.136.0/22 dev tunsnx src 192.168.26.249
172.19.0.0/20 dev tunsnx src 192.168.26.249
172.19.16.0/21 dev tunsnx src 192.168.26.249
172.19.24.0/22 dev tunsnx src 192.168.26.249
172.20.1.0/24 dev tunsnx src 192.168.26.249
172.20.2.0/23 dev tunsnx src 192.168.26.249
172.20.4.0/22 dev tunsnx src 192.168.26.249
172.20.8.0/21 dev tunsnx src 192.168.26.249
172.20.16.0/22 dev tunsnx src 192.168.26.249
172.20.20.0/24 dev tunsnx src 192.168.26.249
172.20.21.1 dev tunsnx src 192.168.26.249
172.20.22.0/23 dev tunsnx src 192.168.26.249
172.20.24.0/22 dev tunsnx src 192.168.26.249
172.20.28.0/23 dev tunsnx src 192.168.26.249
172.20.30.0/24 dev tunsnx src 192.168.26.249
172.20.32.0/23 dev tunsnx src 192.168.26.249
172.20.34.1 dev tunsnx src 192.168.26.249
172.20.40.0/23 dev tunsnx src 192.168.26.249
172.21.0.1 dev tunsnx src 192.168.26.249
172.21.4.1 dev tunsnx src 192.168.26.249
172.21.8.1 dev tunsnx src 192.168.26.249
172.21.12.1 dev tunsnx src 192.168.26.249
172.21.16.1 dev tunsnx src 192.168.26.249
172.21.20.1 dev tunsnx src 192.168.26.249
172.21.24.1 dev tunsnx src 192.168.26.249
172.22.0.1 dev tunsnx src 192.168.26.249
172.22.4.1 dev tunsnx src 192.168.26.249
172.22.8.1 dev tunsnx src 192.168.26.249
172.22.12.1 dev tunsnx src 192.168.26.249
172.22.16.1 dev tunsnx src 192.168.26.249
172.22.20.1 dev tunsnx src 192.168.26.249
172.22.24.1 dev tunsnx src 192.168.26.249
172.23.0.1 dev tunsnx src 192.168.26.249
172.23.4.1 dev tunsnx src 192.168.26.249
172.23.8.1 dev tunsnx src 192.168.26.249
172.23.12.1 dev tunsnx src 192.168.26.249
172.23.16.1 dev tunsnx src 192.168.26.249
172.23.20.1 dev tunsnx src 192.168.26.249
172.23.24.1 dev tunsnx src 192.168.26.249
172.23.28.1 dev tunsnx src 192.168.26.249
172.23.128.1 dev tunsnx src 192.168.26.249
172.24.1.0/24 dev tunsnx src 192.168.26.249
172.24.2.0/24 dev tunsnx src 192.168.26.249
172.24.4.0/24 dev tunsnx src 192.168.26.249
172.24.6.0/24 dev tunsnx src 192.168.26.249
172.24.9.0/24 dev tunsnx src 192.168.26.249
172.24.10.0/24 dev tunsnx src 192.168.26.249
172.25.0.0/24 dev tunsnx src 192.168.26.249
172.25.3.0/24 dev tunsnx src 192.168.26.249
172.25.5.0/24 dev tunsnx src 192.168.26.249
172.25.6.0/23 dev tunsnx src 192.168.26.249
172.25.8.0/24 dev tunsnx src 192.168.26.249
172.25.10.0/23 dev tunsnx src 192.168.26.249
172.25.12.0/22 dev tunsnx src 192.168.26.249
172.25.17.0/24 dev tunsnx src 192.168.26.249
172.25.18.0/23 dev tunsnx src 192.168.26.249
172.25.23.0/24 dev tunsnx src 192.168.26.249
172.25.50.0/23 dev tunsnx src 192.168.26.249
172.25.52.0/24 dev tunsnx src 192.168.26.249
192.168.0.0/23 dev tunsnx src 192.168.26.249
192.168.1.0/24 dev wlp1s0 proto kernel scope link src 192.168.1.142 metric 600
192.168.5.1 dev tunsnx src 192.168.26.249
192.168.8.0/24 dev tunsnx src 192.168.26.249
192.168.26.248 dev tunsnx proto kernel scope link src 192.168.26.249
192.168.30.0/23 dev tunsnx src 192.168.26.249
192.168.32.0/23 dev tunsnx src 192.168.26.249
192.168.44.0/23 dev tunsnx src 192.168.26.249
192.168.52.0/24 dev tunsnx src 192.168.26.249
192.168.55.1 dev tunsnx src 192.168.26.249
192.168.66.0/24 dev tunsnx src 192.168.26.249
192.168.68.0/23 dev tunsnx src 192.168.26.249
192.168.75.0/24 dev tunsnx src 192.168.26.249
192.168.77.1 dev tunsnx src 192.168.26.249
192.168.78.1 dev tunsnx src 192.168.26.249
192.168.88.0/24 dev tunsnx src 192.168.26.249
192.168.99.0/24 dev tunsnx src 192.168.26.249
192.168.130.1 dev tunsnx src 192.168.26.249
192.168.131.1 dev tunsnx src 192.168.26.249
192.168.144.0/24 dev tunsnx src 192.168.26.249
192.168.166.1 dev tunsnx src 192.168.26.249
192.168.188.1 dev tunsnx src 192.168.26.249
192.168.205.0/28 dev tunsnx src 192.168.26.249
192.168.244.0/24 dev tunsnx src 192.168.26.249
```

without VPN:
```
ip link
1: lo: mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
2: wlp1s0: mtu 1500 qdisc noqueue state UP mode DORMANT group default qlen 1000
link/ether 14:ac:60:d8:3f:1f brd ff:ff:ff:ff:ff:ff
altname wlx14ac60d83f1f
```

```
ip route
default via 192.168.1.10 dev wlp1s0 proto dhcp src 192.168.1.142 metric 600
192.168.1.0/24 dev wlp1s0 proto kernel scope link src 192.168.1.142 metric 600
```

Since the connection already worked, I know that there is a way to get it to work, but I don't know why it mysteriously started working and I don't know why it stopped working now. :(

The VPN needs access to kernel modules and the network, so I didn't try unshare options yet.

EDIT: I am able to ping the internal DNS servers, so maybe it is a DNS issue?

EDIT 2: Under /etc/resolve.conf the VPN DNS servers are entered correctly:
```
# Generated by NetworkManager
search hpi.uni-potsdam.de hpi.de openhpi.net openhpi.cloud openhpicloud.de fritz.box
nameserver 10.10.10.12
nameserver 10.10.10.13
nameserver 10.10.10.11
nameserver 191.168.1.10
```

The 10.XX... are the VPN DNS servers

EDIT 3:
Aha, after I verified that the DNS servers are in the resolve.conf, the websites were reachable again. I disconnected and reconnected and now the /etc/resolv.conf only shows:
```
cat /etc/resolv.conf
# Generated by NetworkManager
search fritz.box
nameserver 192.168.1.10
```

So the DNS servers were not entered correctly. Could it be that NetworkManager would need to be triggered to add the DNS servers?

EDIT 4: I can confirm, after manually adding the dns servers to the resolv.conf, the websites are all reachable. :)
Is there a way to make the hosts NetworkManager aware that it needs to update the DNS entries or bind something into the container so snx can tell NetworkManager to update the DNS servers?