Yes it is possible and users on here have acheived it. I recommend doing a search to find these posts. However, Pi 4 isnt a supported configuration yet by 3CX so I would wait if you can or continue down the unsupported route if not.
I have it over 6 sites with no issue.
If you follow that post you can get it working (unsupported) as 3CX server. Or you wait until the upcoming release 16 update 6.You mean as an SBC or 3CX server?
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