境内服务器无法获取到api.weixin.qq.com返回的证书。SSL handshake失败。

境外服务器可以正常进行SSL通信并拿到返回的证书。

具体测试命令如下：

openssl s_client -connect api.weixin.qq.com:443 -servername api.weixin.qq.com -tls1_2

CONNECTED(00000003)

write:errno=104

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no peer certificate available

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No client certificate CA names sent

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SSL handshake has read 4320 bytes and written 0 bytes

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New, (NONE), Cipher is (NONE)

Secure Renegotiation IS supported

Compression: NONE

Expansion: NONE

No ALPN negotiated

SSL-Session:

    Protocol  : TLSv1.2

    Cipher    : 0000

    Session-ID:

    Session-ID-ctx:

    Master-Key:

    Key-Arg   : None

    Krb5 Principal: None

    PSK identity: None

    PSK identity hint: None

    Start Time: 1552387922

    Timeout   : 7200 (sec)

    Verify return code: 0 (ok)