Good afternoon everybody.
Can I migrate version 9 to version 2021? Is there a lot of incompatibility?
Version 2021 can be installed on a server with how many cores?
You can install a new cf version alongside another. There is no provision to upgrade a cf version. At first launch of the cf admin, it would try to identify and offer to import the admin settings of a previous version...but it won't offer that for such a large jump as 9 to 2021.
As for what to expect compatibility-wise, it will vary. Some find the move trivial, some atrocious. No single document or tool exists that will help assess that move. There's a deprecated features page in the cf docs but that covers only a subset of possible compact errors. There's nothing to do but try it. (And while of course you can seek help in the community for issues you may hit, it can be helpful to have the guidance of someone experienced in solving such migrations. I can offer that on a consulting basis, as can others.)
Finally, as for cores, cf imposes no limit on how many it can use. But as for licensing, cf Standard is priced per 2 cores while cf Enterprise is priced per 8 cores.
To add to Charlie's post, I shall say a bit more on code compatibility.
> Can I migrate version 9 to version 2021?
Yes, you can.
> Is there a lot of incompatibility?
No, not a lot. The ColdFusion Team strives to maintain as much backward-compatibility as possible.
You could already check the compatibility of your ColdFusion 9 code as follows:
Analyze subdirectories (checked checkbox)
Analyze file types: CFM, CFC
Validate CFML (checked checkbox)
Version of code to test: CF11