Tag Archives: powershell

Monitoring, Powershell, Script, Windows, Zabbix

Zabbix Error “an array is expected” with Powershell

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When trying to interact with the Zabbix-API via Powershell one might run into the problem, that an API request will not be executed successfully, but an error similar to the following one, will be displayed:

  code message         data                                                           
  ---- -------         ----                                                           
-32602 Invalid params. Invalid parameter "/1/filter/conditions": an array is expected.

Especially when using some code like in the below snippet which uses @(…) and @{…} to define data via arrays and hashtables:

function ZbxUpdateTestAction
{

    $params = @{
        body =  @{
            "jsonrpc"= "2.0"
            "method"= "action.update"
            "params"= @{
                "actionid" = "117"
                "status" = 0
                "filter" = @{
                    "evaltype" = 0
                    "conditions" = @(
                        @{
                            "conditiontype" = 4
                            "operator" = 5
                            "value"= 3
                        }
                        @{
                            "conditiontype" = 0
                            "operator" = 0
                            "value"= 435
                        }
                    )
                }
            }
            "id"= 1
            "auth" = "$api_token"
        } | ConvertTo-Json
        uri = $zbx_api_uri
        headers = @{
            "Content-Type" = "application/json"
            "Authorization" = "Bearer $api_token"
            }
        method = "Post"
    }
    $result = Invoke-WebRequest @params
    return $result.Content | ConvertFrom-Json
}

The above snippet just shows a test function to manually update an action and set conditions to send out alerts for severities of warning or higher for a specific host group.

However – when executed it will fail with the error from snippet 1.

This is because Powershell does the JSON-conversion only to a certain depth. If your structure reaches a deeper level, it will simply stop converting the dict or array which results in the above error.

Troubleshooting it, could be quite a pain in the ass as it’s not that simple to spot and when gradually extending the object it just works fine till you exceed a depth of 2.

To fix this – simple specify the depth for ConvertTo-Json

e.g. 

function ZbxUpdateTestAction
{

    $params = @{
        body =  @{
            "jsonrpc"= "2.0"
            "method"= "action.update"
            "params"= @{
                "actionid" = "117"
                "status" = 0
                "filter" = @{
                    "evaltype" = 0
                    "conditions" = @(
                        @{
                            "conditiontype" = 4
                            "operator" = 5
                            "value"= 3
                        }
                        @{
                            "conditiontype" = 0
                            "operator" = 0
                            "value"= 435
                        }
                    )
                }
            }
            "id"= 1
            "auth" = "$api_token"
        } | ConvertTo-Json -Depth 5
        uri = $zbx_api_uri
        headers = @{
            "Content-Type" = "application/json"
            "Authorization" = "Bearer $api_token"
            }
        method = "Post"
    }
    $result = Invoke-WebRequest @params
    return $result.Content | ConvertFrom-Json
}

Compare line 29 between the two snippets

Refs:

Powershell, Windows

Running into “The parameter is incorrect.” / “HRESULT 0x80070057” when managing scheduled tasks via powershell

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It took me quite some troubleshooting time, but in the end it’s a quite interessting conclusion.

After trying to create a scheduled task that runs every second Saturday per month, I ran into the following error:

Set-ScheduledTask : The parameter is incorrect.
At C:\ITX\itxWindowsUpdate.ps1:436 char:5
+     Set-ScheduledTask -InputObject $task -User $(Get-LocalUser -Name  ...
+     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : InvalidArgument: (PS_ScheduledTask:Root/Microsoft/...S_ScheduledTask) [Set-ScheduledTask], CimException
    + FullyQualifiedErrorId : HRESULT 0x80070057,Set-ScheduledTask

As Windows Powershell is not able to create monthly tasks I used schtasks.exe utility to create the skeleton for the task/minimal task containing the trigger-definition and afterwards manipulate it via powershell to add the missing configuration.

To do so i used Get-ScheduledTask to obtaint he object references for the task and Set-ScheduledTask to write the object again.

Turns out – the task obtained via Get-ScheduledTask contains the trigger defintion for the montly repetition which can’t be handled by powershell and therefor the task itself can not be saved again but results in the above error. 😜

As it seems there are only two ways on how to deal with that problem:
Export the task-definition as an XML and just reimport it via powershell on other systems which require the same configuration (currently untested) or run it daily and deal with the problem within the script.

Lil bit of the debugging-code as a reference for future projects.

Write-Host -ForegroundColor Yellow "Modifying the task"
$action=New-ScheduledTaskAction -Execute "C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe" -Argument '-NoProfile -command "& C:\BLUB\WindowsUpdate\WindowsUpdate.ps1 -reboot_machine 0"'
$principal = New-ScheduledTaskPrincipal -LogonType Password -RunLevel Highest -UserId "$($env:COMPUTERNAME)\Administrator"
#$principal = New-ScheduledTaskPrincipal -RunLevel Highest -UserId "$($env:COMPUTERNAME)\Administrator"

#$task=New-ScheduledTask -Action $action -Description "Daily Update Task for Monitoring and Defender Updates" -Trigger $trigger -Settings $settings -Principal $

$task=$(Get-ScheduledTask -TaskName $task_name -TaskPath \BLUB\)
#$task.Actions=$action
$task.Description="TEST_test"
#$task.Principal=$principal
#Register-ScheduledTask -TaskName $task_name -InputObject $task -TaskPath BLUB -User $(Get-LocalUser -Name Administrator) -Password $password
$task | Set-ScheduledTask -User $(Get-LocalUser -Name Administrator) -Password $password
#-User $(Get-LocalUser -Name Administrator) -Password $password 
#Set-ScheduledTask -TaskPath "BLUB" -TaskName $task_name -Action $action -Principal $principal
#-Principal $principal
# -User $(Get-LocalUser -Name Administrator)

Powershell, Windows

PowerShell AD Snippet

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Simple snippet to get a list when the passwort of a service user was set the last time.

Get-ADUser -Filter 'Name -like "svc*"' -Properties * | select Name,@{name ="pwdLastSet"; expression={[datetime]::FromFileTime($_.pwdLastSet)}}

Requires the Active Directory Powershell module to run.

Command must also be run in an elevated powershell session (Run as Administrator)

Otherwise the pwdLastSet attribute will not be obtained!

Sid To Username

Param
(
    [parameter(
        Mandatory=$true,
        HelpMessage="User SID"
        )
    ]
    [String]
    [alias("sid")]
    $user_sid
)
$objSID = New-Object System.Security.Principal.SecurityIdentifier $user_sid 
$objUser = $objSID.Translate( [System.Security.Principal.NTAccount]) 
$objUser.Value