Air carrier Captain reported GPS interference during cruise. One GPS receiver later recovered and the flight re-established a GPS signal for flight navigation.

Narrative

25 mi east of Cairo FIR boundary (Position KITOT) started to pick up signs of GPS interference. ADS-B R Out; GPS positions L & R blank and GPS display replaced with inertial. We followed FM checklist and guidance for GPS interference or spoofing. We advised Cairo ATC and entered Cairo airspace. GPS interference lasted approximately 65 min until we cleared approximately 12 mi north of the Cairo FIR(position KAVOS). We were able to reestablish GPS navigation but with only one sensor recovered. GPS L remained blank for duration of flight and we received EICAS display GPS L. A maintenance write up was automatically transmitted via the ACARS Left Global Positioning System(GPS) unit failure. Dispatch was notified about the GPS interference as well as an additional maintenance write-up made describing the interference incident as directed by the checklist. Second time I have had a GPS unit not recover while flying this trip. Last time both GPS sensors failed to recover. I thought then that it was due to continued interference but now having only one fail I am wondering if the GPS interference causes some kind of fault in the system that makes it unrecoverable in flight and can only be reset by maintenance on the ground. We may need to look into a software solution or possibly a inflight procedure where we can recover the sensor and or sensors.