NGX_EHOSTUNREACH 1255 src/core/ngx_connection.c         || err == NGX_EHOSTUNREACH)
NGX_EHOSTUNREACH  141 src/event/ngx_event_connect.c                 || err == NGX_EHOSTUNREACH)
NGX_EHOSTUNREACH 1884 src/event/ngx_event_openssl.c             || err == NGX_EHOSTUNREACH)