a 502, 503, or 504 return
code qualifies as a gateway error. When the upstream host is accessed over
an opaque TCP connection, connect timeouts and connection error/failure
events qualify as a gateway error.
This feature is disabled by default or when set to the value 0.</p>
<p>Note that <code>consecutiveGatewayErrors</code> and <code>consecutive5xxErrors</code> can be
used separately or together. Because the errors counted by
<code>consecutiveGatewayErrors</code> are also included in <code>consecutive5xxEr