The user manual and interface for setting up OpenVPN on Advantek’s SR305 leaves much to be desired. I’m going to post what I did to successfully configure it for certificate-based authentication and handling multiple users. Also, since most of the SR305’s I deal with are on machine type internet connections where data use matters, this how-to is for a split-tunnel where OpenVPN clients can access the network they are connecting to, but they will not have access to the remote network’s internet connection.

I think this post will evolve a little over time as I deploy OpenVPN on more of the routers I like to access remotely, this post represents my start. First, we need to set up certificates for the SR305. I did this from my MacBook Pro where I can levereage more computing power, but I think the Advantek SR305 is likely able to do the same stuff if you log into via ssh. Here’s a code dump of what I did to configure certificates and transfer them from the MacBook Pro to the SR305: cd Desktop mkdir SR305 #I made this folder to keep all the certificates and keys in one place for transferring later cd SR305 openssl genrsa -out ca.key 4096 openssl req -x509 -new -nodes -key ca.key -sha256 -days 3650 -out ca.crt -subj "/CN=SR305-CA" openssl genrsa -out sr305-server.key 2048 openssl req -new -key sr305-server.key -out sr305-server.csr -subj "/CN=sr305-server" cat > server_ext.cnf < (switch to a machine that has an OpenVPN server running on it, I happen to have access to a machine that runs fine software from Cutedge Systems, specifically OpenVPN Enabler) cd /usr/local/cutedge/openvpn/sbin ./openvpn --genkey secret ~/Desktop/ta.key (transfer above "ta.key" file to my MacBook Pro's SR305 folder on the desktop and continue there) openssl ca -gencrl -out crl.pem -config openssl.cnf #this command/line can likely be removed openssl genrsa -out client01.key 2048 openssl req -new -key client01.key -out client01.csr -subj "/CN=client01" cat > client_ext.cnf < The commands are mostly done, now we must configure some additional software through the SR305's web interface as follows: ** I forgot what I was going to add here, will get to it later. **