openssl s_client -host linkedin.com -port 443
CONNECTED(00000003)
depth=0 C = US, ST = California, L = Mountain View, O = LinkedIn Corporation, CN = www.linkedin.com
verify error:num=20:unable to get local issuer certificate
verify return:1
depth=0 C = US, ST = California, L = Mountain View, O = LinkedIn Corporation, CN = www.linkedin.com
verify error:num=27:certificate not trusted
verify return:1
depth=0 C = US, ST = California, L = Mountain View, O = LinkedIn Corporation, CN = www.linkedin.com
verify error:num=21:unable to verify the first certificate
verify return:1
---
Certificate chain
0 s:/C=US/ST=California/L=Mountain View/O=LinkedIn Corporation/CN=www.linkedin.com
i:/C=US/O=DigiCert Inc/CN=DigiCert ECC Secure Server CA
---
Server certificate
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
subject=/C=US/ST=California/L=Mountain View/O=LinkedIn Corporation/CN=www.linkedin.com
issuer=/C=US/O=DigiCert Inc/CN=DigiCert ECC Secure Server CA
---
No client certificate CA names sent
---
SSL handshake has read 1281 bytes and written 431 bytes
---
New, TLSv1/SSLv3, Cipher is ECDHE-ECDSA-AES128-GCM-SHA256
Server public key is 256 bit
Secure Renegotiation IS supported
Compression: NONE
Expansion: NONE
SSL-Session:
Protocol : TLSv1.2
Cipher : ECDHE-ECDSA-AES128-GCM-SHA256
Session-ID: 74B5DBAC65147881A14F49AEB0A4D1CC95365582AF19E845486B1FDF002B55D9
Session-ID-ctx:
Master-Key: 30C4A0BB9BE20C920717ED0EF6DB3429A6149E1B8200AF5B3A20B5AB05A44AF5EA29078A81A337D7E602A560B84A674C
Key-Arg : None
PSK identity: None
PSK identity hint: None
SRP username: None
Start Time: 1428608115
Timeout : 300 (sec)
**Verify return code: 21 (unable to verify the first certificate)**
