FortiClient disconnecting immediatly after clicking CONNECT - no error code visible

[NPN]

FortiClient is disconnecting immediatly after clicking connect, debug shows SSL error:

2024-05-29 11:23:15 [308:PLATTLING:1263]allocSSLConn:310 sconn 0x7f47c7b8b000 (1:PLATTLING)
2024-05-29 11:23:15 [308:PLATTLING:1263]SSL state:before SSL initialization (62.159.210.6)
2024-05-29 11:23:15 [308:PLATTLING:1263]SSL state:fatal decode error (62.159.210.6)
2024-05-29 11:23:15 [308:PLATTLING:1263]SSL state:error:(null)(62.159.210.6)
2024-05-29 11:23:15 [308:PLATTLING:1263]SSL_accept failed, 1:unexpected eof while reading
2024-05-29 11:23:15 [308:PLATTLING:1263]Destroy sconn 0x7f47c7b8b000, connSize=0. (PLATTLING)
2024-05-29 11:23:15 [309:PLATTLING:1274]allocSSLConn:310 sconn 0x7f47c7b21000 (1:PLATTLING)
2024-05-29 11:23:15 [309:PLATTLING:1274]SSL state:before SSL initialization (62.159.210.6)
2024-05-29 11:23:15 [309:PLATTLING:1274]SSL state:fatal decode error (62.159.210.6)
2024-05-29 11:23:15 [309:PLATTLING:1274]SSL state:error:(null)(62.159.210.6)
2024-05-29 11:23:15 [309:PLATTLING:1274]SSL_accept failed, 1:unexpected eof while reading
2024-05-29 11:23:15 [309:PLATTLING:1274]Destroy sconn 0x7f47c7b21000, connSize=0. (PLATTLING)

It goes on a loop like that, anybody had this problem?

FortiClient#FortiGate #VPN #SSL

[hbac]

Hi @NPN,

FortiClient logs will be useful. Please refer to this article: https://community.fortinet.com/t5/FortiClient/Technical-Tip-How-to-enable-debug-log-in-FortiClient/t...

Regards, 

[Pittstate]

@NPN Is there any additional debugging info before or after this for additional context?

Grasping, but maybe a protocol mismatch between server and client that won't allow them to progress in negotiations?

I've had something similar appear in logs, but this has not been a show stopper:

2024-06-12 14:59:22 [24619:root:1db]allocSSLConn:312 sconn 0x7f4338a34800 (0:root)
2024-06-12 14:59:22 [24619:root:1db]SSL state:before SSL initialization (104.143.49.76)
2024-06-12 14:59:22 [24619:root:1db]SSL state:fatal decode error (104.143.49.76)
2024-06-12 14:59:22 [24619:root:1db]SSL state:error:(null)(104.143.49.76)
2024-06-12 14:59:22 [24619:root:1db]SSL_accept failed, 1:unexpected eof while reading
2024-06-12 14:59:22 [24619:root:1db]Destroy sconn 0x7f4338a34800, connSize=0. (root)
2024-06-12 14:59:22 [24620:root:1da]allocSSLConn:312 sconn 0x7f4338a34800 (0:root)
2024-06-12 14:59:22 [24620:root:1da]SSL state:before SSL initialization (104.143.49.76)
2024-06-12 14:59:22 [24620:root:1da]SSL state:before SSL initialization (104.143.49.76)
2024-06-12 14:59:22 [24620:root:1da]got SNI server name: test-vpn.pittstate.edu realm (null)
2024-06-12 14:59:22 [24620:root:1da]client cert requirement: no
2024-06-12 14:59:22 [24620:root:1da]SSL state:SSLv3/TLS read client hello (104.143.49.76)
2024-06-12 14:59:22 [24620:root:1da]SSL state:SSLv3/TLS write server hello (104.143.49.76)
2024-06-12 14:59:22 [24620:root:1da]SSL state:SSLv3/TLS write change cipher spec (104.143.49.76)
2024-06-12 14:59:22 [24620:root:1da]SSL state:TLSv1.3 early data (104.143.49.76)
2024-06-12 14:59:22 [24620:root:1da]SSL state:TLSv1.3 early data:(null)(104.143.49.76)
2024-06-12 14:59:22 [24620:root:1da]SSL state:TLSv1.3 early data (104.143.49.76)