I'm using Powershell to set up IIS bindings on a web server, and having a problem with the following code:
$serverIps = gwmi Win32_NetworkAdapterConfiguration
| Where { $_.IPAddress }
| Select -Expand IPAddress
| Where { $_ -like '*.*.*.*' }
| Sort
if ($serverIps.length -le 1) {
Write-Host "You need at least 2 IP addresses for this to work!"
exit
}
$primaryIp = $serverIps[0]
$secondaryIp = $serverIps[1]
If there's 2+ IPs on the server, fine - Powershell returns an array, and I can query the array length and extract the first and second addresses just fine.
Problem is - if there's only one IP, Powershell doesn't return a one-element array, it returns the IP address (as a string, like "192.168.0.100") - the string has a .length property, it's greater than 1, so the test passes, and I end up with the first two characters in the string, instead of the first two IP addresses in the collection.
How can I either force Powershell to return a one-element collection, or alternatively determine whether the returned "thing" is an object rather than a collection?
Define the variable as an array in one of two ways...
Wrap your piped commands in parentheses with an # at the beginning:
$serverIps = #(gwmi Win32_NetworkAdapterConfiguration
| Where { $_.IPAddress }
| Select -Expand IPAddress
| Where { $_ -like '*.*.*.*' }
| Sort)
Specify the data type of the variable as an array:
[array]$serverIps = gwmi Win32_NetworkAdapterConfiguration
| Where { $_.IPAddress }
| Select -Expand IPAddress
| Where { $_ -like '*.*.*.*' }
| Sort
Or, check the data type of the variable...
IF ($ServerIps -isnot [array])
{ <error message> }
ELSE
{ <proceed> }
Force the result to an Array so you could have a Count property. Single objects (scalar) do not have a Count property. Strings have a length property so you might get false results, use the Count property:
if (#($serverIps).Count -le 1)...
By the way, instead of using a wildcard that can also match strings, use the -as operator:
[array]$serverIps = gwmi Win32_NetworkAdapterConfiguration -filter "IPEnabled=TRUE" | Select-Object -ExpandProperty IPAddress | Where-Object {($_ -as [ipaddress]).AddressFamily -eq 'InterNetwork'}
You can either add a comma(,) before return list like return ,$list or cast it [Array] or [YourType[]] at where you tend to use the list.
If you declare the variable as an array ahead of time, you can add elements to it - even if it is just one...
This should work...
$serverIps = #()
gwmi Win32_NetworkAdapterConfiguration
| Where { $_.IPAddress }
| Select -Expand IPAddress
| Where { $_ -like '*.*.*.*' }
| Sort | ForEach-Object{$serverIps += $_}
You can use Measure-Object to get the actual object count, without resorting to an object's Count property.
$serverIps = gwmi Win32_NetworkAdapterConfiguration
| Where { $_.IPAddress }
| Select -Expand IPAddress
| Where { $_ -like '*.*.*.*' }
| Sort
if (($serverIps | Measure).Count -le 1) {
Write-Host "You need at least 2 IP addresses for this to work!"
exit
}
Return as a referenced object, so it never converted while passing.
return #{ Value = #("single data") }
I had this problem passing an array to an Azure deployment template. If there was one object, PowerShell "converted" it to a string. In the example below, $a is returned from a function that gets VM objected according to the value of a tag. I pass the $a to the New-AzureRmResourceGroupDeployment cmdlet by wrapping it in #(). Like so:
$TemplateParameterObject=#{
VMObject=#($a)
}
New-AzureRmResourceGroupDeployment -ResourceGroupName $RG -Name "TestVmByRole" -Mode Incremental -DeploymentDebugLogLevel All -TemplateFile $templatePath -TemplateParameterObject $TemplateParameterObject -verbose
VMObject is one of the template's parameters.
Might not be the most technical / robust way to do it, but it's enough for Azure.
Update
Well the above did work. I've tried all the above and some, but the only way I have managed to pass $vmObject as an array, compatible with the deployment template, with one element is as follows (I expect MS have been playing again (this was a report and fixed bug in 2015)):
[void][System.Reflection.Assembly]::LoadWithPartialName("System.Web.Extensions")
foreach($vmObject in $vmObjects)
{
#$vmTemplateObject = $vmObject
$asJson = (ConvertTo-Json -InputObject $vmObject -Depth 10 -Verbose) #-replace '\s',''
$DeserializedJson = (New-Object -TypeName System.Web.Script.Serialization.JavaScriptSerializer -Property #{MaxJsonLength=67108864}).DeserializeObject($asJson)
}
$vmObjects is the output of Get-AzureRmVM.
I pass $DeserializedJson to the deployment template' parameter (of type array).
For reference, the lovely error New-AzureRmResourceGroupDeployment throws is
"The template output '{output_name}' is not valid: The language expression property 'Microsoft.WindowsAzure.ResourceStack.Frontdoor.Expression.Expressions.JTokenExpression'
can't be evaluated.."
There is a way to deal with your situation. Leave most of you code as-is, just change the way to deal with the $serverIps object. This code can deal with $null, only one item, and many items.
$serverIps = gwmi Win32_NetworkAdapterConfiguration
| Where { $_.IPAddress }
| Select -Expand IPAddress
| Where { $_ -like '*.*.*.*' }
| Sort
# Always use ".Count" instead of ".Length".
# This works on $null, only one item, or many items.
if ($serverIps.Count -le 1) {
Write-Host "You need at least 2 IP addresses for this to work!"
exit
}
# Always use foreach on a array-possible object, so that
# you don't have deal with this issue anymore.
$serverIps | foreach {
# The $serverIps could be $null. Even $null can loop once.
# So we need to skip the $null condition.
if ($_ -ne $null) {
# Get the index of the array.
# The #($serverIps) make sure it must be an array.
$idx = #($serverIps).IndexOf($item)
if ($idx -eq 0) { $primaryIp = $_ }
if ($idx -eq 1) { $secondaryIp = $_ }
}
}
In PowerShell Core, there is a .Count property exists on every objects. In Windows PowerShell, there are "almost" every object has an .Count property.
I'm building a script that will compare the last octed of in-use IPv4 addreses, with all the available octeds (2 till 254).
I am already this far that I do get a result by comparing array's, but my end-result is also an array, and I cannot seem to get only the number.
My script:
$guestIP = #("192.168.31.200","192.168.31.31","192.168.31.90","192.168.31.25","192.168.31.100")
$AllLastOcted = $("2","3","4","5","6","7","8","9","10","11","12","13","14","15","16","17","18","19","20","21","22","23","24","25","26","27","28","29","30","31","32","33","34","35","36","37","38","39","40","41","42","43","44","45","46","47","48","49","50","51","52","53","54","55","56","57","58","59","60","61","62","63","64","65","66","67","68","69","70","71","72","73","74","75","76","77","78","79","80","81","82","83","84","85","86","87","88","89","90","91","92","93","94","95","96","97","98","99","100","101","102","103","104","105","106","107","108","109","110","111","112","113","114","115","116","117","118","119","120","121","122","123","124","125","126","127","128","129","130","131","132","133","134","135","136","137","138","139","140","141","142","143","144","145","146","147","148","149","150","151","152","153","154","155","156","157","158","159","160","161","162","163","164","165","166","167","168","169","170","171","172","173","174","175","176","177","178","179","180","181","182","183","184","185","186","187","188","189","190","191","192","193","194","195","196","197","198","199","200","201","202","203","204","205","206","207","208","209","210","211","212","213","214","215","216","217","218","219","220","221","222","223","224","225","226","227","228","229","230","231","232","233","234","235","236","237","238","239","240","241","242","243","244","245","246","247","248","249","250","251","252","253","254")
$guestIP = $guestIP | sort -Property {$_-replace '[\d]'},{$_-replace '[a-zA-Z\p{P}]'-as [int]}
$AllLastOcted = $AllLastOcted | sort -Property {$_-replace '[\d]'},{$_-replace '[a-zA-Z\p{P}]'-as [int]}
$guestIP = $guestIP -replace('192.168.31.','')
Compare-Object -ReferenceObject ($AllLastOcted ) -DifferenceObject ($guestIP) | select -Property InputObject -First 1 | set-Variable AvailableOcted -PassThru
$AvailableOcted
My goal is, is that I have as result the first-available octed that I can use.
like:
write-host "IP that can be used is 192.168.31.$AvailableOcted"
PS > IP that can used is 192.168.31.2
You can simplify this a lot.
Instead of defining all numbers from 2 to 254 you can use the range operator to create the array. You also don't need the [int] casts. Instead of using the Compare-Object cmdlet to filter the octeds, you can use the Where-Object cmdlet:
$guestIP = #("192.168.31.200","192.168.31.31","192.168.31.90","192.168.31.25","192.168.31.100")
$AllLastOcted = 2 .. 254
$usedOcted = $guestIP -replace '.*\.'
$nextAvailableOcted = $AllLastOcted | Where { $_ -NotIn $usedOcted } | select -first 1
write-host "IP that can be used is 192.168.31.$nextAvailableOcted"
Output:
IP that can be used is 192.168.31.2
Well, as simple as:
$AvailableOcted.InputObject
would return only the value.
So it would look like this:
write-host ("IP that can be used is 192.168.31." + $AvailableOcted.InputObject)
I'm using Powershell to set up IIS bindings on a web server, and having a problem with the following code:
$serverIps = gwmi Win32_NetworkAdapterConfiguration
| Where { $_.IPAddress }
| Select -Expand IPAddress
| Where { $_ -like '*.*.*.*' }
| Sort
if ($serverIps.length -le 1) {
Write-Host "You need at least 2 IP addresses for this to work!"
exit
}
$primaryIp = $serverIps[0]
$secondaryIp = $serverIps[1]
If there's 2+ IPs on the server, fine - Powershell returns an array, and I can query the array length and extract the first and second addresses just fine.
Problem is - if there's only one IP, Powershell doesn't return a one-element array, it returns the IP address (as a string, like "192.168.0.100") - the string has a .length property, it's greater than 1, so the test passes, and I end up with the first two characters in the string, instead of the first two IP addresses in the collection.
How can I either force Powershell to return a one-element collection, or alternatively determine whether the returned "thing" is an object rather than a collection?
Define the variable as an array in one of two ways...
Wrap your piped commands in parentheses with an # at the beginning:
$serverIps = #(gwmi Win32_NetworkAdapterConfiguration
| Where { $_.IPAddress }
| Select -Expand IPAddress
| Where { $_ -like '*.*.*.*' }
| Sort)
Specify the data type of the variable as an array:
[array]$serverIps = gwmi Win32_NetworkAdapterConfiguration
| Where { $_.IPAddress }
| Select -Expand IPAddress
| Where { $_ -like '*.*.*.*' }
| Sort
Or, check the data type of the variable...
IF ($ServerIps -isnot [array])
{ <error message> }
ELSE
{ <proceed> }
Force the result to an Array so you could have a Count property. Single objects (scalar) do not have a Count property. Strings have a length property so you might get false results, use the Count property:
if (#($serverIps).Count -le 1)...
By the way, instead of using a wildcard that can also match strings, use the -as operator:
[array]$serverIps = gwmi Win32_NetworkAdapterConfiguration -filter "IPEnabled=TRUE" | Select-Object -ExpandProperty IPAddress | Where-Object {($_ -as [ipaddress]).AddressFamily -eq 'InterNetwork'}
You can either add a comma(,) before return list like return ,$list or cast it [Array] or [YourType[]] at where you tend to use the list.
If you declare the variable as an array ahead of time, you can add elements to it - even if it is just one...
This should work...
$serverIps = #()
gwmi Win32_NetworkAdapterConfiguration
| Where { $_.IPAddress }
| Select -Expand IPAddress
| Where { $_ -like '*.*.*.*' }
| Sort | ForEach-Object{$serverIps += $_}
You can use Measure-Object to get the actual object count, without resorting to an object's Count property.
$serverIps = gwmi Win32_NetworkAdapterConfiguration
| Where { $_.IPAddress }
| Select -Expand IPAddress
| Where { $_ -like '*.*.*.*' }
| Sort
if (($serverIps | Measure).Count -le 1) {
Write-Host "You need at least 2 IP addresses for this to work!"
exit
}
Return as a referenced object, so it never converted while passing.
return #{ Value = #("single data") }
I had this problem passing an array to an Azure deployment template. If there was one object, PowerShell "converted" it to a string. In the example below, $a is returned from a function that gets VM objected according to the value of a tag. I pass the $a to the New-AzureRmResourceGroupDeployment cmdlet by wrapping it in #(). Like so:
$TemplateParameterObject=#{
VMObject=#($a)
}
New-AzureRmResourceGroupDeployment -ResourceGroupName $RG -Name "TestVmByRole" -Mode Incremental -DeploymentDebugLogLevel All -TemplateFile $templatePath -TemplateParameterObject $TemplateParameterObject -verbose
VMObject is one of the template's parameters.
Might not be the most technical / robust way to do it, but it's enough for Azure.
Update
Well the above did work. I've tried all the above and some, but the only way I have managed to pass $vmObject as an array, compatible with the deployment template, with one element is as follows (I expect MS have been playing again (this was a report and fixed bug in 2015)):
[void][System.Reflection.Assembly]::LoadWithPartialName("System.Web.Extensions")
foreach($vmObject in $vmObjects)
{
#$vmTemplateObject = $vmObject
$asJson = (ConvertTo-Json -InputObject $vmObject -Depth 10 -Verbose) #-replace '\s',''
$DeserializedJson = (New-Object -TypeName System.Web.Script.Serialization.JavaScriptSerializer -Property #{MaxJsonLength=67108864}).DeserializeObject($asJson)
}
$vmObjects is the output of Get-AzureRmVM.
I pass $DeserializedJson to the deployment template' parameter (of type array).
For reference, the lovely error New-AzureRmResourceGroupDeployment throws is
"The template output '{output_name}' is not valid: The language expression property 'Microsoft.WindowsAzure.ResourceStack.Frontdoor.Expression.Expressions.JTokenExpression'
can't be evaluated.."
There is a way to deal with your situation. Leave most of you code as-is, just change the way to deal with the $serverIps object. This code can deal with $null, only one item, and many items.
$serverIps = gwmi Win32_NetworkAdapterConfiguration
| Where { $_.IPAddress }
| Select -Expand IPAddress
| Where { $_ -like '*.*.*.*' }
| Sort
# Always use ".Count" instead of ".Length".
# This works on $null, only one item, or many items.
if ($serverIps.Count -le 1) {
Write-Host "You need at least 2 IP addresses for this to work!"
exit
}
# Always use foreach on a array-possible object, so that
# you don't have deal with this issue anymore.
$serverIps | foreach {
# The $serverIps could be $null. Even $null can loop once.
# So we need to skip the $null condition.
if ($_ -ne $null) {
# Get the index of the array.
# The #($serverIps) make sure it must be an array.
$idx = #($serverIps).IndexOf($item)
if ($idx -eq 0) { $primaryIp = $_ }
if ($idx -eq 1) { $secondaryIp = $_ }
}
}
In PowerShell Core, there is a .Count property exists on every objects. In Windows PowerShell, there are "almost" every object has an .Count property.