Make HAProxy match multiple conditions for HTTP health checking

The solution is to use to the raw tcp-check and write a health check script sequence which match all the conditions.

For example, you want to ensure the server’s response has: 

HTTP status code is 200 

absence of keyword Error

1 2 3 4 5 6 7 8 9 10

backend myapp [...]  option tcp-check  tcp-check send GET\ /my/check/url\ HTTP/1.1\r\n  tcp-check send Host:\ myhost\r\n  tcp-check send Connection:\ close\r\n  tcp-check send \r\n  tcp-check expect string HTTP/1.1\ 200\ OK  tcp-check expect ! string Error

Source: https://alohalb.wordpress.com/2012/10/12/scalable-waf-protection-with-haproxy-and-apache-with-modsecurity/

https://alohalb.wordpress.com/2012/10/12/scalable-waf-protection-with-haproxy-and-apache-with-modsecurity/


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https://www.haproxy.com/documentation/aloha/10-0/traffic-management/lb-layer7/health-checks/

Equivalent of the configuration above, with all default options:

backend bk_myapp
        [...]
        option httpchk OPTIONS / HTTP/1.0
        http-check expect rstatus (2|3)[0-9][0-9]
        default-server inter 3s fall 3 rise 2
        server srv1 10.0.0.1:80 check
        server srv2 10.0.0.2:80 check