Single label domain in AD (Single label domain) - Needs to be renamed. It was firma. - needed in firma.local?

Question

System administration

So the question is - what pitfalls do I expect when renaming and is it worth renaming at all, maybe it's easier to break everything and create another forest?
I’ll clarify right away:
- the domain and the forest are old - it has been stretching since 2000
- several domain controllers (3pcs)
- the level of the forest and the domain (2008)
- a lot of servers and workstations, terminals and the like ...
- No Exchange
In general, I understand what to break and build again - this is "Best Practice" as they say ... but I want to understand all aspects of the problem

Answer 1

info sea just ad renaming the domain
10 years ago renamed xxx to xxx.local- no pitfalls happened
ps and the best-of-the-best-practices - make backups of everything and everything, as if you would break and raise everything a new forest with 0. and if you have a normal 5-day week, then on Friday evening, stock up pizza / tea / coffee:
- dispersal of accountants and other workaholics
- backups, with the expectation of "everything from 0"
- and with a light soul try to spend renaming. if you break everything - by Monday you will have time to create a new world forest
pps why do you need? maybe it's easier not to break, but to create subdomains in the forest? *.com *.ru *.local and so on, between them there is a trust by design, and a variegated transfer of servers / jobs, who goes where (although for the internal kitchen OU seemed to be enough for the ears)

Answer 2

There are no big problems. The procedure is repeatedly described in the documentation. The only thing .local is not needed is not supported in certificates (you will have to use only self-signed ones).