one domain return 502

[lemon9921010]

Many upstream works, but this domain return 502 How can I debug? conf like this local ok, err = hc.spawn_checker{ shm = 'healthcheck', -- defined by 'lua_shared_dict' upstream = 'test', -- defined by 'upstream' type = 'http',

        http_req = 'GET /status HTTP/1.0\r\nHost: healthcheck.nxin.com\r\n\r\n',
                -- raw HTTP request for checking

        interval = 2000,  -- run the check cycle every 2 sec
        timeout = 1000,   -- 1 sec is the timeout for network operations
        fall = 3,  -- # of successive failures before turning a peer down
        rise = 2,  -- # of successive successes before turning a peer up
        valid_statuses = {200, 302, 301,401,402,403, 404},  -- a list valid HTTP status code
        concurrency = 10,  -- concurrency level for test requests
    }

request respones below

curl 10.21.1.11:8080/status -v

• About to connect() to 10.21.1.11 port 8080 (#0)
• Trying 10.21.1.11...
• Connected to 10.21.1.11 (10.21.1.11) port 8080 (#0)

  GET /status HTTP/1.1 User-Agent: curl/7.29.0 Host: 10.221.14.110:8080 Accept: /

  < HTTP/1.1 302 < Location: https:

[lemon9921010]

app need agent, conf like below. closed http_req = 'GET /status HTTP/1.0\r\nUser-Agent: LuaSocket 3.0-rc1\r\n\r\n'