HAProxy Enterprise Documentation 1.8r2
connect directive to enable SNI, connect over SSL/TLS, perform health checks over SOCKS4, and choose the protocol, such as HTTP/2 or FastCGI. Here's an example where health checks are performed using HTTP/2 and SSL:
backend be_myapp option httpchk http-check connect ssl alpn h2 http-check send meth HEAD uri
/healthver HTTP/2 hdr Host www.test.local server srv1 192.168.1.5:443 check
To close a connection cleanly instead of sending a RST, use the
For the complete list of parameters that can be specified on the
connect line, see http-check connect.
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