[root@mx etc]# openssl s_client -starttls smtp -crlf -connect mx.bestariwebhost.co.id:587
CONNECTED(00000003)
depth=0 CN = mx.bestariwebhost.co.id
verify error:num=20:unable to get local issuer certificate
verify return:1
depth=0 CN = mx.bestariwebhost.co.id
verify error:num=27:certificate not trusted
verify return:1
depth=0 CN = mx.bestariwebhost.co.id
verify error:num=21:unable to verify the first certificate
verify return:1
---
Certificate chain
0 s:/CN=mx.bestariwebhost.co.id
i:/C=US/O=Let's Encrypt/CN=Let's Encrypt Authority X3
---
Server certificate
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
subject=/CN=mx.bestariwebhost.co.id
issuer=/C=US/O=Let's Encrypt/CN=Let's Encrypt Authority X3
---
No client certificate CA names sent
Server Temp Key: ECDH, prime256v1, 256 bits
---
SSL handshake has read 2268 bytes and written 408 bytes
---
New, TLSv1/SSLv3, Cipher is ECDHE-RSA-AES256-GCM-SHA384
Server public key is 2048 bit
Secure Renegotiation IS supported
Compression: NONE
Expansion: NONE
SSL-Session:
Protocol : TLSv1.2
Cipher : ECDHE-RSA-AES256-GCM-SHA384
Session-ID: FD2D45A8F2B155E74D85CBE41F9D4B323A31348913801536E6139387B7868653
Session-ID-ctx:
Master-Key: 88AA5937AEB2B74B229F4760DA7E07499778DF54908C0473B2998984FF6DCA667AEA67A74D994E3F75987E8B46AFF40F
Key-Arg : None
Krb5 Principal: None
PSK identity: None
PSK identity hint: None
TLS session ticket lifetime hint: 200 (seconds)
TLS session ticket:
0000 - 6a d4 c3 e5 2a 99 e1 c2-f0 00 88 ed b5 46 e3 8c j...*........F..
0010 - fd cf 63 f2 0d b9 21 96-a9 19 28 70 28 9d 98 b5 ..c...!...(p(...
0020 - e1 97 e8 61 b6 86 a0 bd-2c 62 2c 9e eb bb a5 3a ...a....,b,....:
0030 - be 52 2f 50 3e ad 09 4d-03 e3 c3 cf 8b 38 76 a2 .R/P>..M.....8v.
0040 - 48 0b 2e 66 0e 27 ff 43-4c 8e 84 2f 0f cc c6 9c H..f.'.CL../....
0050 - 7a 35 1e 31 38 10 0f 38-a3 cd c8 3b 9d 3e e0 54 z5.18..8...;.>.T
0060 - 21 61 7b 93 dc 59 5d b5-44 55 44 49 8b c0 a6 6d !a{..Y].DUDI...m
0070 - 99 74 85 a9 b6 c0 30 f1-e3 ee d1 71 49 5d 1e 19 .t....0....qI]..
0080 - 10 70 3f fd 42 fc d4 66-e6 22 09 eb 1e 92 92 08 .p?.B..f."......
0090 - bf d4 7e a7 8e 3f 38 b1-9d 10 00 6e 55 fe a6 9d ..~..?8....nU...
Start Time: 1501647417
Timeout : 300 (sec)
Verify return code: 21 (unable to verify the first certificate)
---
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