I am unable to connect to APNs sandbox push endpoint from our backend servers. It works fine when hitting the request from my local machine but it fails from the infra servers. Here are the complete curl details. Endpoint: https://api.sandbox.push.apple.com:443 CURL request and response: curl -v https://api.sandbox.push.apple.com:443 Trying 17.188.168.149:443... Connected to api.sandbox.push.apple.com (17.188.168.149) port 443 ALPN: curl offers h2,http/1.1 Cipher selection: ALL:!EXPORT:!EXPORT40:!EXPORT56:!aNULL:!LOW:!RC4:@STRENGTH TLSv1.2 (OUT), TLS handshake, Client hello (1): CAfile: /etc/pki/tls/certs/ca-bundle.crt CApath: none OpenSSL SSL_connect: SSL_ERROR_SYSCALL in connection to api.sandbox.push.apple.com:443 Closing connection curl: (35) OpenSSL SSL_connect: SSL_ERROR_SYSCALL in connection to api.sandbox.push.apple.com:443 There are no issues with Production endpoint. Can someone help? Verified all certificates. Everything worked fine until 29th July but started failing since 30th July Here is the PCAP file. Additionally, Here is the outbound public IP : 3.251.214.255 apple_push_sandbox_pcap.txt

I am unable to connect to APNs sandbox push endpoint from our backend servers. It works fine when hitting the request from my local machine but it fails from the infra servers. Here are the complete curl details. Endpoint: https://api.sandbox.push.apple.com:443 CURL request and response: curl -v https://api.sandbox.push.apple.com:443 Trying 17.188.168.149:443... Connected to api.sandbox.push.apple.com (17.188.168.149) port 443 ALPN: curl offers h2,http/1.1 Cipher selection: ALL:!EXPORT:!EXPORT40:!EXPORT56:!aNULL:!LOW:!RC4:@STRENGTH TLSv1.2 (OUT), TLS handshake, Client hello (1): CAfile: /etc/pki/tls/certs/ca-bundle.crt CApath: none OpenSSL SSL_connect: SSL_ERROR_SYSCALL in connection to api.sandbox.push.apple.com:443 Closing connection curl: (35) OpenSSL SSL_connect: SSL_ERROR_SYSCALL in connection to api.sandbox.push.apple.com:443 There are no issues with Production endpoint. Can someone help? Verified all certificates. Everything worked fine until 29th July but started failing since 30th July