Hi, I work on an ecommerce website that has a Windows ERP server (like a mainframe, but newer, that has our product data) that I need to connect to from both a test Linux (Redhat) web server and a live Linux (Redhat) web server. I want to be able to copy files from both of them to the Windows Server, and to contact the Windows Server's SQL Server.

I have implemented stunnel and am able to contact SQL Server correctly from both right now, but I want to move to a site-to-site VPN now that I have to also copy files up to the Windows server. I also imagine there will be more passing of things back and forth between each Linux box and the Windows server in the future. VPN seems like the easiest and most streamlined way for me to go.

Question 1: Can there be 2 site-to-site VPNs, one from each of the Linux servers, set up to access the same Windows server?

Question 2: Should I use samba for file transfer, or something else? If samba, do I just need to install the samba client on the Linux boxes, or is there a Windows component to this as well?

I'm kind of a newb about Linux/Windows interconnections and the best way to do these things. Any help or further information to read would be really appreciated. Thank you!