(SQL Server) Check Internet Connectivity

Demonstrates an efficient way to test for Internet connectivity.

Chilkat ActiveX Downloads ActiveX for 32-bit and 64-bit Windows

-- Important: See this note about string length limitations for strings returned by sp_OAMethod calls.
--
CREATE PROCEDURE ChilkatSample
AS
BEGIN
    DECLARE @hr int
    -- Important: Do not use nvarchar(max).  See the warning about using nvarchar(max).
    DECLARE @sTmp0 nvarchar(4000)
    DECLARE @success int
    SELECT @success = 0

    DECLARE @socket int
    EXEC @hr = sp_OACreate 'Chilkat.Socket', @socket OUT
    IF @hr <> 0
    BEGIN
        PRINT 'Failed to create ActiveX component'
        RETURN
    END

    -- 1. Use a reliable Anycast IP. 
    --    8.8.8.8 (Google) or 1.1.1.1 (Cloudflare) are the industry standards.
    DECLARE @targetIp nvarchar(4000)
    SELECT @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).
    DECLARE @port int
    SELECT @port = 53

    -- 3. Disable SSL (0). 
    --    We are not doing a handshake, just a TCP connection.
    DECLARE @ssl int
    SELECT @ssl = 0

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

    -- Connect
    EXEC sp_OAMethod @socket, 'Connect', @success OUT, @targetIp, @port, @ssl, @timeoutMs
    IF @success = 0
      BEGIN
        EXEC sp_OAGetProperty @socket, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @socket
        RETURN
      END

    EXEC sp_OAMethod @socket, 'Close', @success OUT, 10


    PRINT 'We have Internet connectivity.'

    EXEC @hr = sp_OADestroy @socket


END
GO