curl liefert das auf Port 443:
--- curl Start
C:\Users\<DerUser>>curl -v -X POST -d 'bla3000' https://www.<DerServer>.de:443/gateway_callback
Note: Unnecessary use of -X or --request, POST is already inferred.
* Trying <DieAdresse>...
* TCP_NODELAY set
* Connected to www.<DerServer>.de (<DieAdresse>) port 443 (#0)
* schannel: SSL/TLS connection with www.<DerServer>.de port 443 (step 1/3)
* schannel: checking server certificate revocation
* schannel: sending initial handshake data: sending 186 bytes...
* schannel: sent initial handshake data: sent 186 bytes
* schannel: SSL/TLS connection with www.<DerServer>.de port 443 (step 2/3)
* schannel: failed to receive handshake, need more data
* schannel: SSL/TLS connection with www.<DerServer>.de port 443 (step 2/3)
* schannel: encrypted data got 1832
* schannel: encrypted data buffer: offset 1832 length 4096
* schannel: sending next handshake data: sending 126 bytes...
* schannel: SSL/TLS connection with www.<DerServer>.de port 443 (step 2/3)
* schannel: encrypted data got 274
* schannel: encrypted data buffer: offset 274 length 4096
* schannel: SSL/TLS handshake complete
* schannel: SSL/TLS connection with www.<DerServer>.de port 443 (step 3/3)
* schannel: stored credential handle in session cache
> POST /gateway_callback HTTP/1.1
> Host: www.<DerServer>.de
> User-Agent: curl/7.55.1
> Accept: */*
> Content-Length: 9
> Content-Type: application/x-www-form-urlencoded
>
* upload completely sent off: 9 out of 9 bytes
* schannel: client wants to read 102400 bytes
* schannel: encdata_buffer resized 103424
* schannel: encrypted data buffer: offset 0 length 103424
* schannel: encrypted data got 520
* schannel: encrypted data buffer: offset 520 length 103424
* schannel: decrypted data length: 491
* schannel: decrypted data added: 491
* schannel: decrypted data cached: offset 491 length 102400
* schannel: encrypted data buffer: offset 0 length 103424
* schannel: decrypted data buffer: offset 491 length 102400
* schannel: schannel_recv cleanup
* schannel: decrypted data returned 491
* schannel: decrypted data buffer: offset 0 length 102400
< HTTP/1.1 301 Moved Permanently
< Date: Thu, 20 Feb 2020 16:41:02 GMT
< Content-Type: text/html; charset=iso-8859-1
< Content-Length: 255
< Connection: keep-alive
< Server: Apache
< Location: https://www.<DerServer>.de/gateway_callback/
<
<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN">
<html><head>
<title>301 Moved Permanently</title>
</head><body>
<h1>Moved Permanently</h1>
<p>The document has moved <a href="https://www.<DerServer>.de/gateway_callback/">here</a>.</p>
</body></html>
* Connection #0 to host www.<DerServer>.de left intact