Elastic basic License version ELK use in production server

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1

i saw both apache 2 version and elastic license version when i am downloading ELK.

Can i use elastic basic license version ELK for my customer in their production server ?

or should i use apache 2.0 versioned ELK ?

2

Yes you can.

3

do I need to pay for the basic license to use in production?

currently I am using apache 2 version

4

No you don't have to pay for the basic license.
You don't even have to tell elastic you are using it.