<div dir="ltr">Hi<br><br>I have a problem with the upstream round robin mechanism.<br>in
ngx_http_upstream.c ngx_http_upstream_server function the hostname that
is added in the configuration file under upstream directive is added to
the upstream server list.<br>
the function uses ngx_parse_url which in turn uses ngx_parse_inet_url that calls ngx_inet_resolve_host.<br>ngx_inet_resolve_host
tries to resolve the host name from the configuration file by calling
gethostbyname. for each url gethostbyname return the list of ip's that
are associated with this url and these ip's are added to the list of
upstream servers.<br>
This results in a situation that if there are three servers defined in
an upstream directive, each with an equal weight, but one of those
server is associated with two ip's (for example internal and an external
ip) then the round robin weight will not be equal for each server. The
server which has two ip's will get a double weight.<br>
i can add a log if required or if my explanation is not good enough.<br>i
saw that a url has a flag called one_addr that if is set to true will
get resolved to a single ip only, but this flag is not used.<br><br>adding the host ip address is one way to solve this, is there another way?</div>