we have a 4 root (dedicated) servers (no virtual servers/vservers, full hardware servers with asus mainboards and 6 real Intel cores) running Debian hosted by another company and standing in their location. Each server has its own IPv4 and multiple services are running on those machines.
My aim is to connect all 4 server to a private network with private IP addresses (something 192.168.x.x) on a virtual network interface. Later I would like to bind special services like mysql database only to the virtual interface and block most traffic on the public interface (eth0) with iptables. Also there should be a directory somewhere in the filesystem of each server which holds synched content for all 4 servers.
What kind of software solution should I use to configure this setup? Is this done with OpenVPN? Or some other solution?
We don't need hard encryption on the wire with big keys as the speed matters most.
Thanks for any hint, Simon
I would split your case to 2 separate questions:
Yeah sounds doable with openvpn, however keep in mind that you need to have openvpn server somewhere. This will be single point of failure and also potential perf. bottleneck.
What I would do: In case I had money to spent : I would contact ISP/DataCenter you're using, and ask for L2VPN solution. What they usually do is they are using MPLS to get you the transparent and scalable configuration between DCs. In case of not having the shitload of money, I would research multipoint VPN software. Example : http://sourceforge.net/projects/opennhrp/ . IMO a lot better approach then OpenVPN one.
You can either use plain NFS to get this going (again - single point of failure and bottleneck though). Or try to see if any of distributed shared FS would work work you. Examples : GPFS, glusterfs