There is a procedure for this. You file your divorce petition and apply to the court for an "order of notice". The court will then order you to provide notice to your ex, most often by way of publication in a newspaper. You need to follow that order by publishing the exact words of the court order exactly as the court tells you, and then you make a return of service sending a copy of the legal notice and signing a statement that you are in compliance with the order of notice. After that, the case proceeds as usual, and if he does not show up for various hearings, he can be held in default and the divorce will eventually be granted.
I highly reccoment that you retain a divorce practitioner to do this for you because the rules of procedure can present a bit of a challenge.
This answer is provided for informational purposes only. Actual legal advice can only be provided in an office consultation by an attorney licensed in your jurisdiction, with experience in the area of law in which your concern lies.
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