[PeterisP]

Something like this to obviously distinguish environments is good practice - at one company we implemented scripts for terminal color-coding like this after some downtime caused by a destructive backup restore accidentally being run in the production environment instead of an acceptance testing system, which was in all aspects identical to the production system.

And I've seen a solution for more secure environments where physical separation was used with the operator having separate monitors/keyboards, and the "important" system having a different color keyboard and monitor frame.