Moving the route definitions to global scope, and defining an address
pool, will allow other clients besides *dhatch-d4b* to connect to and
use the OpenVPN tunnel service. This may be useful in situations where
IPsec is blocked
The VPN capability of the UniFi Security Gateway is extremely limited.
It does not support road-warrior IPsec/IKEv2 configuration, and its
OpenVPN configuration is inflexible. As with DHCP, the best solution is
to simply move service to another machine.
To that end, I created a new VM, *vpn0.pyrocufflink.blue*, to host both
strongSwan and OpenVPN. For this to work, the necessary TCP/UDP ports
need to be forwarded, of course, and all of the remote subnets need
static routes on the gateway, specifying this machine as the next hop.
Additionally, ICMP redirects need to be disabled, to prevent confusing
the routing tables of devices on the same subnet as the VPN gateway.
The routes to FireMon networks are now defined using the
`firemon_networks` Ansible variable. The global `iroute` and
client-specific `route` options are generated from the CIDR blocks
specified in this list.
The `ifconfig` global directive specifies the IP address added to the
tunnel interface device, not the network. The `push route` directives
need to include this address to correctly send route information to
clients.
The *dch-openvpn-server* role installs and configures OpenVPN and
stunnel to provide both native OpenVPN service as well as
OpenVPN-over-TLS. The latter uses stunnel, listening on TCP port 9876,
to allow better firewall traversal and TCP port sharing via reverse
proxy.
Dustin