Java – What happens if the IPN service for PayPal cannot connect to the IPN destination?

I was wondering about this when writing the IPN receiver in Java, it will be used to handle IPN automatically because the actual software runs in Java. The IPN processor is a class in my project to speed up processing and avoid PHP in the middle.

However, this question comes to mind when I think of notification guarantees. When the host is unavailable, PayPal resend the IPN post request? Or is it just discarded and handled by the administrator? This is because it is highly likely that the server will undergo maintenance every two days, at which point the server will not be in an active state.

What is the delay if the notification is resent?

Thanks in advance. 🙂

Please check the details:

Does PayPal resend IPN publish requests when the host is unavailable? Or is it simply discarded and handled by the administrator?

Yes. If your server does not acknowledge the POST message or your server is unreachable, PayPal will continue to send you IPN messages.

What is the

delay if the notification is resent?

According to PayPal document , PayPal will periodically resend the message until you respond, but the interval between retries increases with each attempt. The IPN will be resent for up to four days with up to 15 retries. After each failed attempt, the interval increases.