Running into this error?

502 Bad Gateway
The server returned an invalid or incomplete response.

This error only popped up when keepalived was started.  Otherwise just with HAproxy, a timeout was seen. It appeared as if it was a keepalived config error.  In this case, it was due to a faulty HAproxy configuration:

[root@jenkins01 jenkins]# diff /etc/haproxy/haproxy.cfg-diff01 /etc/haproxy/haproxy.cfg
46c46
<     server         jenkins01.nix.mds.xyz    jenkins01.nix.mds.xyz:10443 ssl check check-ssl verify none
—
>     server         jenkins01.nix.mds.xyz    jenkins01.nix.mds.xyz:10443 check check-ssl verify none
[root@jenkins01 jenkins]#

The ssl directive was missing from one of the lines above.

Cheers,
Tom
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