We use Windows Server for three things: 1. Directory services/DC 2. Windows file shares 3. Exchange I have to buy user CALs for #1 and #2. One CAL gives me

We use Windows Server for three things: 1. Directory services/DC 2. Windows file shares 3. Exchange I have to buy user CALs for #1 and #2. One CAL gives me the right to connect that user to any of our file shares and to AD. IIRC, that cost when we last purchased was around $50/user. We also have to buy a separate CAL for Exchange. I would love to replace AD and our Windows file shares with Samba 4, provided that it was a stable, viable replacement which didn't add a lot of overhead for our admins. Exchange is a separate issue, and one we're currently exploring Zimbra as a possibility. It's early days yet there. Almost everything else in our environment is Linux.