Invoke-WebRequest -Login

I am trying to loginto a web application called Thruk… it is using the OMD version.

I am using invoke-webrequest to use a websession to try and connect to a local thruk omd instance. I am trying to correlate the forms the best i can from the examples but when I try and submit the web session the output just keeps going back to the login page.

This is the following code I run:

add-type @"
using System.Net;
using System.Security.Cryptography.X509Certificates;
public class TrustAllCertsPolicy : ICertificatePolicy {
    public bool CheckValidationResult(
        ServicePoint srvPoint, X509Certificate certificate,
        WebRequest request, int certificateProblem) {
            return true;
[System.Net.ServicePointManager]::CertificatePolicy = New-Object TrustAllCertsPolicy

$login = Invoke-WebRequest "https://icinga/bcmonitoring/thruk/cgi-bin/login.cgi?bcmonitoring/thruk/" -SessionVariable fb
$login.Forms[0].Fields.loginuser = $cred.UserName
$login.Forms[0].Fields.password = $cred.GetNetworkCredential().Password
$UAstring = "Firefox"
$mainPage = Invoke-WebRequest ("https://icinga/bcmonitoring/thruk/cgi-bin/login.cgi?bcmonitoring/thruk/") -WebSession $fb -Body $login -Method Post -UserAgent $UAstring 

This is the output:

The above is just an excerpt. Any help will be most appreciated…

Here’s what I came up with using the Thrunk Demo page.

#Initialize Session
$R=Invoke-WebRequest -SessionVariable thrunksession

#Set Login and Password

$R=Invoke-WebRequest -Uri ("" + $R.Forms[0].Action) -WebSession $thrunksession -Method POST -Body $R.Forms[0].Fields

$R=Invoke-WebRequest -Uri ("") -WebSession $thrunksession -Method POST

Thanks @Curtis!

I compared and contrasted your code and saw that the difference that you had was


where I put it as loginuser

Thats because that is what i see in the output:

Id Method Action    Fields                                                     
-- ------ ------    ------                                                     
   post   login.cgi {[referer, ], [loginuser, ], [password, ], [submit, Login]}

I am curious why is that powershell understood login instead of login user. Is this how it is designed?

loginuser is the ID of the field, but the name of the filed is login.

Oh, so i am assuming you were looking at the inputfields property?

innerHTML : 
innerText : 
outerHTML : 
outerText : 
tagName   : INPUT
id        : loginuser
class     : logininput
name      : login

I actually used the developer tools of IE and/or Chrome to look at the form html on the page.