Returns the wrong HTTP state

[Rhythmicc]

Hello, HTTP LOAD cannot return the correct response code when using HTTP LOAD for LAN access.

I've tried following ways to prove the url is accessible.

import requests

res = requests.get('http://ip:port/index.html')
print(res.status_code) # output 200

and I managed to access the url using my browser.

but if I run: http_load -p 5 -s 5 urls, it returns:

1018 fetches, 5 max parallel, 189348 bytes, in 5.00144 seconds
186 mean bytes/connection
203.541 fetches/sec, 37858.7 bytes/sec
msecs/connect: 3.77434 mean, 16.716 max, 1.92 min
msecs/first-response: 3.95721 mean, 16.698 max, 2.099 min
HTTP response codes:
  code 403 -- 1018

I wonder why it returns code 403?