{"id":1296,"date":"2009-03-19T05:40:33","date_gmt":"2009-03-19T13:40:33","guid":{"rendered":"http:\/\/www.sapien.com\/blog\/2009\/03\/19\/get-network-connections\/"},"modified":"2009-03-19T05:40:33","modified_gmt":"2009-03-19T13:40:33","slug":"get-network-connections","status":"publish","type":"post","link":"https:\/\/dev.sapien.com\/blog\/2009\/03\/19\/get-network-connections\/","title":{"rendered":"Get Network Connections"},"content":{"rendered":"

I love that part of my job is helping people out in the forums as ScriptingAnswers.com<\/a>. A recent post asked about finding out what network drives were mapped on a remote computer using PowerShell. The task sounded familiar so I poked around my script pile and found an old VBScript that used WMI and the Win32_NetworkConnection class. Great. Get-WMIObject to the rescue:<\/p>\n

PS C:\\> Get-WMIObject win32_networkconnection -computername Desk23<\/font><\/p>\n

You even get a nicely formatted summary. But you me, I can’t resist tinkering so I wrote a function that enhances this basic command I call Get-NetConnections.<\/p>\n

\n
\n
Function Get-NetConnections {<\/pre>\n
    Param([string]$computername=$env:computername,<\/pre>\n
          [switch<\/span>]$progress)<\/pre>\n
 <\/pre>\n
   #turn off the error pipeline<\/span><\/pre>\n
   $ErrorActionPreference=\"SilentlyContinue\"<\/span><\/pre>\n
 <\/pre>\n
    #trap errors, display a message and continue<\/span><\/pre>\n
    Trap {<\/pre>\n
        Write-Warning \"Error connecting to $computername\"<\/span><\/pre>\n
        Continue<\/pre>\n
    }<\/pre>\n
 <\/pre>\n
    #make $computername upper case for looks<\/span><\/pre>\n
    $computername=$computername.ToUpper()<\/pre>\n
    <\/pre>\n
    if<\/span> ($progress) {<\/pre>\n
    #if -progress is specified use Write-Progress to display what<\/span><\/pre>\n
    #is happening<\/span><\/pre>\n
     Write-Progress -Activity \"Getting Network Connections\"<\/span> -status $computername `<\/pre>\n
     -currentoperation \"Executing Get-WMIObject Win32_NetworkConnection -computername $computername\"<\/span><\/pre>\n
    }<\/pre>\n
    #get WMI information. Turn off error notification<\/span><\/pre>\n
    $connections=Get-WmiObject win32_networkconnection -computername $computername -ea \"Stop\"<\/span><\/pre>\n
    <\/pre>\n
    #validate connections were returned<\/span><\/pre>\n
    if<\/span> (!$connections) {<\/pre>\n
        Write-Host \"No network connections found on $computername\"<\/span> -foregroundcolor RED -backgroundcolor Yellow<\/pre>\n
        Return $null<\/pre>\n
    }<\/pre>\n
    <\/pre>\n
    if<\/span> ($progress) {<\/pre>\n
    Write-Progress -Activity \"Getting Network Connections\"<\/span> -status $computername `<\/pre>\n
    -currentoperation \"Parsing results\"<\/span><\/pre>\n
    }<\/pre>\n
    <\/pre>\n
    $connections | select @{Name=\"Computer\"<\/span>;Expression={$_.__SERVER}},`<\/pre>\n
    @{Name=\"LocalName\"<\/span>;Expression = {$_.LocalName.toUpper()}},`<\/pre>\n
    @{Name=\"RemoteComputer\"<\/span>;Expression={<\/pre>\n
    #use regular expression to match the first part of the UNC<\/span><\/pre>\n
    $_.RemotePath -match<\/span> \"[^\\\\]+\"<\/span> | Out-Null<\/pre>\n
    ($matches.Item(0)).ToUpper()<\/pre>\n
    }},RemotePath,Status,ConnectionState<\/pre>\n
}<\/pre>\n<\/div>\n<\/div>\n
The function takes a computername as a parameter but defaults to the local computername. Because I realized you may want to process a list of computers and the WMI command takes a little bit of time to run, I thought having some sort of progress indication would be helpful. If you use -progress, then Write-Progress<\/strong> is called to display the current operation and status.<\/p>\n
\n
\n
if<\/span> ($progress) {<\/pre>\n
    #if -progress is specified use Write-Progress to display what<\/span><\/pre>\n
    #is happening<\/span><\/pre>\n
     Write-Progress -Activity \"Getting Network Connections\"<\/span> -status $computername `<\/pre>\n
     -currentoperation \"Executing Get-WMIObject Win32_NetworkConnection -computername $computername\"<\/span><\/pre>\n
    }<\/pre>\n<\/div>\n<\/div>\n
The main part of the function is the WMI command.<\/p>\n
\n
\n
#get WMI information. Turn off error notification<\/span><\/pre>\n
    $connections=Get-WmiObject win32_networkconnection -computername $computername -ea \"Stop\"<\/span><\/pre>\n
 <\/pre>\n<\/div>\n<\/div>\n
You’ll notice that I’m setting the common parameter -ErrorAction to “Stop”. This is because if there is an error connecting to the computer I want an exception to be raised so my Trap handler will be called.<\/p>\n
\n
\n
#turn off the error pipeline<\/span><\/pre>\n
   $ErrorActionPreference=\"SilentlyContinue\"<\/span><\/pre>\n
 <\/pre>\n
    #trap errors, display a message and continue<\/span><\/pre>\n
    Trap {<\/pre>\n
        Write-Warning \"Error connecting to $computername\"<\/span><\/pre>\n
        Continue<\/pre>\n
    }<\/pre>\n<\/div>\n<\/div>\n
I also turned off the Error pipeline to suppress any messages. But this makes me responsible for any error handling, which I do here. I also create my own notification should there be no mapped drives.<\/p>\n
\n
\n
#validate connections were returned<\/span><\/pre>\n
    if<\/span> (!$connections) {<\/pre>\n
        Write-Host \"No network connections found on $computername\"<\/span> -foregroundcolor RED -backgroundcolor Yellow<\/pre>\n
        Return $null<\/pre>\n
    }<\/pre>\n<\/div>\n<\/div>\n
Assuming there are mapped drives found, I picked some properties that I felt you would be most interested in and tried to make them a little more user friendly. One property that I added is the remote computer name which I pull from the remote path using a regular expression.<\/p>\n
\n
\n
$connections | select @{Name=\"Computer\"<\/span>;Expression={$_.__SERVER}},`<\/pre>\n
   @{Name=\"LocalName\"<\/span>;Expression = {$_.LocalName.toUpper()}},`<\/pre>\n
   @{Name=\"RemoteComputer\"<\/span>;Expression={<\/pre>\n
   #use regular expression to match the first part of the UNC<\/span><\/pre>\n
   $_.RemotePath -match<\/span> \"[^\\\\]+\"<\/span> | Out-Null<\/pre>\n
   ($matches.Item(0)).ToUpper()<\/pre>\n
   }},RemotePath,Status,ConnectionState<\/pre>\n<\/div>\n<\/div>\n
I realize there are other ways to use REGEX here  but I wanted to stick with basic PowerShell. Here’s a sample of what you can expect:<\/p>\n
Computer        : CHAOS
LocalName       : M:
RemoteComputer  : JDH-NVNAS
RemotePath      : \\\\jdh-nvnas\\media
Status          : OK
ConnectionState : Connected <\/font><\/p>\n
Computer        : CHAOS
LocalName       : W:
RemoteComputer  : WIN2K801
RemotePath      : \\\\win2k801\\c$
Status          : Unavailable
ConnectionState : Disconnected <\/font><\/p>\n
Computer        : CHAOS
LocalName       : X:
RemoteComputer  : JDH-NVNAS
RemotePath      : \\\\jdh-nvnas\\files\\vms\\esx
Status          : OK
ConnectionState : Connected <\/font><\/p>\n
Computer        : CHAOS
LocalName       : Y:
RemoteComputer  : JDHIT-DC01
RemotePath      : \\\\jdhit-dc01\\c$
Status          : OK
ConnectionState : Connected <\/font><\/p>\n
Computer        : CHAOS
LocalName       : Z:
RemoteComputer  : JDH-NVNAS
RemotePath      : \\\\jdh-nvnas\\files\\vms
Status          : OK
ConnectionState : Connected<\/font> <\/p>\n
Naturally there are many ways you can use this function.  Here are some examples.<\/p>\n
PS C:\\>Get-NetConnections -computer “File01” -progress 
<\/font>PS C:\\> get-content computers.txt | foreach {
<\/font>>> get-netconnections -computer $_ -progress} | 
<\/font>>> Where {$_.status -ne “OK”} | Export-CSV problems.csv
<\/font>>>
<\/font>PS C:\\> #if you have the Quest cmdlets installed
PS C:\\> $data=get-qadcomputer | foreach {
>> <\/font>get-netconnections -computer $_.name -progress}
>><\/font>
PS C:\\> $data | sort RemotePath | 
>> format-table -groupby RemotePath Computer,LocalName,Status<\/font> <\/p>\n
These examples assume you’ve loaded the function into your PowerShell session.<\/p>\n<\/p>\n
\n
Download the script file here.<\/a><\/p>\n<\/div>\n
Enjoy!<\/p>\n","protected":false},"excerpt":{"rendered":"
I love that part of my job is helping people out in the forums as ScriptingAnswers.com. A recent post asked about finding out what network drives were mapped on a remote computer using PowerShell. The task sounded familiar so I poked around my script pile and found an old VBScript that used WMI and the Win32_NetworkConnection class. Great. Get-WMIObject to the rescue:<\/p>\n
Get-WMIObject win32_networkconnection -computername Desk23<\/p>\n
You even get a nicely formatted summary. But you me, I can’t resist tinkering so I wrote a function that enhances this basic command I call Get-NetConnection<\/p>\n","protected":false},"author":3,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"footnotes":""},"categories":[25],"tags":[475,198,221,28,477,476,474,35,275],"class_list":["post-1296","post","type-post","status-publish","format-standard","hentry","category-windows-powershell","tag-erroractionpreference","tag-function","tag-network","tag-powershell","tag-regular-expression","tag-trap","tag-win32_netconnection","tag-wmi","tag-write-progress"],"jetpack_featured_media_url":"","_links":{"self":[{"href":"https:\/\/dev.sapien.com\/blog\/wp-json\/wp\/v2\/posts\/1296","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/dev.sapien.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/dev.sapien.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/dev.sapien.com\/blog\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/dev.sapien.com\/blog\/wp-json\/wp\/v2\/comments?post=1296"}],"version-history":[{"count":0,"href":"https:\/\/dev.sapien.com\/blog\/wp-json\/wp\/v2\/posts\/1296\/revisions"}],"wp:attachment":[{"href":"https:\/\/dev.sapien.com\/blog\/wp-json\/wp\/v2\/media?parent=1296"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/dev.sapien.com\/blog\/wp-json\/wp\/v2\/categories?post=1296"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/dev.sapien.com\/blog\/wp-json\/wp\/v2\/tags?post=1296"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}