3rd party VPN on dual NIC system problems

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1

I am running F42 server on a machine with two NICs. One NIC is connected to secure LAN. The other is connected to DMZ. Appropriate firewall rules are in place. For routing, the default route is set for the WAN NIC, and all local traffic is set for the LAN NIC. On the LAN, there is a DHCP/DNS server that handles local queries. All of this works fine, and has for several years.

Now I am using a 3rd party VPN, NordVPN, for WAN traffic. . But when the VPN is connected, I get only half speed throughput.to the WAN. I think the routing may be mixed up:


[ken@Foghorn openvpn]$ ip r
default via 10.100.0.1 dev tun0 proto static metric 50 
default via 192.168.0.1 dev enp2s0 proto dhcp src 192.168.0.109 metric 100 
10.100.0.0/16 dev tun0 proto kernel scope link src 10.100.0.2 metric 50 
185.255.130.119 via 192.168.0.1 dev enp2s0 proto static metric 50 
192.168.0.0/24 dev enp2s0 proto kernel scope link src 192.168.0.109 metric 100 
192.168.0.1 dev enp2s0 proto static scope link metric 50 
192.168.1.0/24 dev enp0s31f6 proto kernel scope link src 192.168.1.107 metric 101 
[ken@Foghorn openvpn]$

Nord’s DNS leak test shows the two DNS servers for my ISP (which I believe it shouldn’t). What am I missing?

All help appreciated.

TIA

ken

2

VPN overrides you default WAN route.
Any VPN negatively affects performance due to encryption overhead.
OpenVPN is particularly slow as it runs in user space.
Use WireGuard for better performance.

Check the output while the VPN is connected:

resolvectl status --no-pager