Symptoms
The following errors appear in /var/log/watchdog/instance1.log:
Checking ApacheAdmin@test.tld
====================
Logging in...
==> curl https://test.tld/servlet/Turbine/frm/single/event1234submit/doLogin/action/PLoginHandler/op_name/0/referer/test.tld
ApacheAdmin responce on login:
empty
bw_id:
No cookie received
or
Checking Apache@test.tld
====================
Sending HTTPS request:
==> GET / HTTPS/1.1 Host: test.tld:443
Reply received:
HTTP/1.0 900 NET OR SSL ERROR
SSL_connect 17815: 1 - error:1407742E:SSL routines:SSL23_GET_SERVER_HELLO:tlsv1 alert protocol version
Web page received:
Server returrned empty page
or
Checking Apache@test.tld
====================
Sending HTTPS request:
==> GET / HTTPS/1.1 Host: resellers.test.tld:443
Reply received:
HTTP/1.0 900 NET OR SSL ERROR
SSL_connect 17821: 1 - error:1407742E:SSL routines:SSL23_GET_SERVER_HELLO:tlsv1 alert protocol version
Web page received:
Server returrned empty page
Such errors began to appear as soon as the list of available SSL protocols was changed in /etc/httpd/conf.d/ssl.conf on the 'affected' servers:
# grep SSLProtocol /etc/httpd/conf.d/ssl.conf
SSLProtocol -all +TLSv1.2
Cause
Watchdog server is deployed on RHEL 5 which does not support TLS higher than v1.0. This information could be found on the official RHEL site.
Resolution
Currently there is no stable workaround. Please check the following knowledge base article.