document the ganeti naming convention

policy/tpa-rfc-6-naming-convention.md

@@ -76,6 +76,16 @@ Another naming scheme is `role-ID`, where:
    one, to distinguish between multiple instances of the same server
    (e.g. `mon-01`, `mon-02`)
 
+Some machines do include a location name, when their location is
+actually at least as important as their function. For example, the
+Ganeti clusters are named like `gnt-LOC` where `LOC` is the location
+(example, `gnt-fsn` is in Falkenstein, Germany). Nodes inside the
+cluster are named `LOC-node-ID` (e.g. `fsn-node-01` for the first
+Ganeti node in the `gnt-fsn` cluster).
+
+Other servers may be named using that convention, for example,
+`dal-rescue-01` is a rescue box hosted near the `gnt-dal` cluster.
+
 ## Location
 
 Note that this naming scheme is deprecated. Favor role-based names,