HTTP健康检查过数据不正确

[zhanglaotang2020]

nginx/1.17.9
built by gcc 4.8.5 20150623 (Red Hat 4.8.5-39) (GCC)
built with OpenSSL 1.0.2k-fips 26 Jan 2017
TLS SNI support enabled
configure arguments: --with-http_ssl_module --with-pcre --with-http_stub_status_module --add-module=../nginx_upstream_check_module-master/

健康检查配置监控：
location /upstream_status {
check_status json;

        access_log   off;
    }

配置集群：
upstream test {
server 172.16.74.200:8090 weight=1;
server 172.16.74.200:8100 weight=1;
check interval=1000 rise=2 fall=3 timeout=1000 type=http;
check_keepalive_requests 1000;
check_http_send "HEAD /api/a/b/c/getversion HTTP/1.0\r\n\r\n";
check_http_expect_alive http_2xx http_3xx;
}
在生产场景中，172.16.74.200:8090 节点端口不通，但是返回的json数据正常。
未在其他场景复现

[yaoweibin]

后端的响应是怎么样的？