Lowercase, no punctuation
Names are all lowercase with no hyphens or underscores inside. Each part is recognised by its position and length.
A name is for life
A machine keeps its name until it's retired. If its job or location changes, it's rebuilt under a new name rather than renamed.
Friendly names are aliases
Easy names like wiki.internode.in are just pointers to a real machine name. When a service moves, the pointer moves with it.
The provider isn't in the name
Machines move between cloud providers more often than they change city or job, so the provider is recorded internally instead.
Backup sites are still production
A disaster-recovery copy of a live system is named as production, just at a different site.
Retired names rest for a year
When a machine is retired, its number isn't reused for 12 months, so old references can't point at a new machine by accident.