SYMPTOM:
In a scenario where push notifications aren't being delivered, the DSSErrors.log may contain the following error messages:
MSIDeliveryEngine::hDelivery(): Unknown Delivery Failed. Error string from ExecuteMultiProcess Error: MMobile::MobileSenderImpl::hSendToAPNS - couldn't connect a socket. Error Code 0x800647C2. MMobile::MobileSenderImpl::hSendToAPNS - couldn't resolve a host. Error Code 0x800647C2.
The Apple push service uses a load balancing scheme that yields a different IP address for the same hostname. However, the entire 17.0.0.0/8 address block is assigned to Apple - this range can be specified in firewall rules.
WARNING:
The third-party product(s) discussed in this technical note is manufactured by vendors independent of Strategy. Strategy makes no warranty, express, implied or otherwise, regarding this product, including its performance or reliability.