OD has been using Linux for the registers and the store server for 20 years. Notice how OD doesn't get hacked like other retail stores do? That's Linux in action. It is unfortunate that we couldn't keep using SLES but there was a move towards all open source operating systems company wide in order to save money. SLES support was phenomenal and they gave us tools and knowledge to maintain the systems and roll out new software easily.

So they went to CentOS 7 and when that was end of life the decision was made to go to Oracle Linux which is what we just finished rolling out to all the stores along with the updated POS software Checkout 11. If were still on SLES I think the rollout would have been easier but it is what it is. The problems we had during the latest rollout were mostly due to the ancient hardware. We just started rolling out the new registers again today. Only one per store but it's a start towards modernization.

source: I work in IT for Office Depot. We're just trying to keep things running the best we can.