我写了一个python应用程序，它向Apple设备发送推送通知。
所有iOS应用程序都不再收到通知。
看起来Apple在发送通知后会返回错误。
我想知道以下回复是否正常？或者证书是否存在问题？
$ openssl s_client -connect gateway.push.apple.com:2195 -cert /home/ubuntu/webapps/notification/certificates/relax_app/production/apns-dev-cert.pem -key /home/ubuntu/webapps/notification/certificates/relax_app/production/apns-dev-key-noenc.pem
CONNECTED(00000003)
depth=1 C = US, O = "Entrust, Inc.", OU = www.entrust.net/rpa is incorporated by reference, OU = "(c) 2009 Entrust, Inc.", CN = Entrust Certification Authority - L1C
verify error:num=20:unable to get local issuer certificate
verify return:0
140149704410784:error:14094415:SSL routines:SSL3_READ_BYTES:sslv3 alert certificate expired:s3_pkt.c:1195:SSL alert number 45
140149704410784:error:1409E0E5:SSL routines:SSL3_WRITE_BYTES:ssl handshake failure:s3_pkt.c:591:
---
Certificate chain
0 s:/C=US/ST=California/L=Cupertino/O=Apple Inc./OU=iTMS Engineering/CN=gateway.push.apple.com
i:/C=US/O=Entrust, Inc./OU=www.entrust.net/rpa is incorporated by reference/OU=(c) 2009 Entrust, Inc./CN=Entrust Certification Authority - L1C
1 s:/C=US/O=Entrust, Inc./OU=www.entrust.net/rpa is incorporated by reference/OU=(c) 2009 Entrust, Inc./CN=Entrust Certification Authority - L1C
i:/O=Entrust.net/OU=www.entrust.net/CPS_2048 incorp. by ref. (limits liab.)/OU=(c) 1999 Entrust.net Limited/CN=Entrust.net Certification Authority (2048)
---
Server certificate
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
subject=/C=US/ST=California/L=Cupertino/O=Apple Inc./OU=iTMS Engineering/CN=gateway.push.apple.com
issuer=/C=US/O=Entrust, Inc./OU=www.entrust.net/rpa is incorporated by reference/OU=(c) 2009 Entrust, Inc./CN=Entrust Certification Authority - L1C
---
No client certificate CA names sent
---
SSL handshake has read 2670 bytes and written 2047 bytes
---
New, TLSv1/SSLv3, Cipher is AES256-SHA
Server public key is 2048 bit
Secure Renegotiation IS supported
Compression: NONE
Expansion: NONE
SSL-Session:
Protocol : SSLv3
Cipher : AES256-SHA
Session-ID:
Session-ID-ctx:
Master-Key: F2FEDB49795DA0B3084B850521A514EB60EE9959C40753AB79B799CA4F6225DAA4FE7084B8CF6D7BF9A4AEB92B9B3A06
Key-Arg : None
PSK identity: None
PSK identity hint: None
Start Time: 1385498375
Timeout : 7200 (sec)
Verify return code: 20 (unable to get local issuer certificate)
---
注意
响应返回以下内容： 验证错误：num = 20：无法获得本地颁发者证书
此错误会阻止发送推送通知吗？还是可以忽略？
提前致谢。