Lua

Check Internet Connectivity

See more Socket/SSL/TLS Examples

Demonstrates an efficient way to test for Internet connectivity. Lua

local chilkat = require("chilkat")

local socket = chilkat.Socket.new()
-- 1. Use a reliable Anycast IP.
--    8.8.8.8 (Google) or 1.1.1.1 (Cloudflare) are the industry standards.
local targetIp = "8.8.8.8"

-- 2. Use Port 53 (DNS).
--    DNS servers typically listen on TCP Port 53 as well as UDP.
--    (Alternatively, use port 443 if you suspect port 53 is blocked).
local port = 53

-- 3. Disable SSL (0).
--    We are not doing a handshake, just a TCP connection.
local ssl = false

-- 4. Short Timeout (1500ms).
--    If you can't reach Google in 1.5 seconds, the connection is
--    likely too poor for practical use anyway.
local timeoutMs = 1500

-- Connect
local success = socket:connect(targetIp, port, ssl, timeoutMs)
if not success then
    print(socket.last_error_text)
    return
end

socket:close(10)

print("We have Internet connectivity.")