Using Switch -RegEx to create Custom Object (Getting HBA Info)
The other day I had a need to collect HBA (Host Base Fiber Adapters) from all my Servers. So the first place I looked was at WMI, but unfortunately… no dice. It didnt have the information I needed. The only way I knew to get the info I needed was to use was HBACmd.exe (utility to collect HBA information remotely.) So I went to writing a wrapper script in powershell to call the exe and then grep the text for what I was looking for, but I thought… HEY! Thats not the powershell thing to do! We do objects not text. So I went to parsing the text and making an object out of it. The script below is the result and while I dont believe many of you will find it particularly useful as it has a VERY specific use, I wanted to share with you how I went about objectizing the output.
Here is a littel Q and A on the script
Q: Purpose?
A: To get all the HBA information include Type, Firmware, Bios, Target Lun, WWN and a slew of other stuff.
Q: Why Did I objectize my text?
A: Because I know can simply use properties to filter and output data. Like what Machines have what Bios and what type of HBAs they have. Before I would have the parse the text for every different senario… now I just use where-object and filter away.
I few things that I wanted to point out here are the use of Switch to create the Custom Objects. IMO, Switch is one of the most powerful commands in the Powershell Language. It is INSANELY Powerfull. To be honest, It is pretty much the only one you need.
To compare it “Select Case” in vbscript would be insulting, but it can peform a similar function Like
Value1 {"It was Value 1"}
Value2 {"It was Value 2"}
Value3 {"It was Value 3"}
Value4 {"It was Value 4"}
}
It would take a whole series of post to completely cover switch, but for this one I only want to go over -regex use. For complete use read the help located:
PS> Get-help About_Switch # Read it, Learn it, Love it
Some Quick Notes about Switch
- Can use RegEx, WildCard, Exact, CaseSensitive, or File options.
- It takes input via Pipeline {expression} or File. The cool thing is the pipeline can be any expression that results in piped output.
- For each match it can perform any ScritpBlock use $_ as the current Item
- It performs EVERY match on each element unless you use Continue after a match to stop processing that record
Like I said, Switch is insanely powerful. Just one of those powers is using RegEx for comparison.
Here is an example of using the -RegEx option
{
"^\d" {"Starts with number: " + $_.FullName}
"\d" {"Has a number in it: " + $_.FullName}
"[^A-Za-z]" {"Does NOT start with Number: " + $_.FullName}
"tmp" {"Has ‘tmp’ in it: " + $_.FullName}
# Notice that you can even use and expression to match
{$_.Mode -match "-a"} {"Has Archive Bit Set: " + $_.FullName}
}
Now.. lets look at the script below. You will noticed I used RegEx to decide what value gets put in to what property of the object.
The script converts the output of three commands into two different objects. Lets look at one of them
It takes text like This
Port WWN : 10:00:00:00:11:11:11:11
Node WWN : 20:00:00:00:11:11:11:11
Fabric Name: 00:00:00:00:00:00:00:00
Flags : 0000f0a5
Host Name : Server1
Mfg : Emulex Corporation
Port WWN : 10:00:00:00:22:22:22:22
Node WWN : 20:00:00:00:22:22:22:22
Fabric Name: 00:00:00:00:00:00:00:00
Flags : 0000f0a5
Host Name : Server1
Mfg : Emulex Corporation
And converts Into an object like This
Name MemberType Definition
—- ———- ———-
Equals Method System.Boolean Equals(Object obj)
GetHashCode Method System.Int32 GetHashCode()
GetType Method System.Type GetType()
ToString Method System.String ToString()
Fabric NoteProperty System.String Fabric=00:00:00:00:00:00:00:00
Flags NoteProperty System.String Flags=0000f0a5
HBADetail NoteProperty System.Object[] HBADetail=System.Object[]
Host NoteProperty System.String Host=Server1
LUN NoteProperty System.String LUN=01
MFG NoteProperty System.String MFG=Emulex Corporation
NodeWWN NoteProperty System.String NodeWWN=20:00:00:00:11:11:11:11
PortWWN NoteProperty System.String PortWWN=10:00:00:00:11:11:11:11
Here is the Script
Begin{
$erroractionpreference = "SilentlyContinue"
$HBACMDPath = "<path To HbaCmd.exe>"
function CreateHBAListObj{
Param($srv)
$objCol = @()
$result = &"$HBACMDPath" "h=$srv" ListHBAs
foreach($item in $result)
{
$parsd = $item.split([string[]](": "),[system.StringSplitOptions]::RemoveEmptyEntries)
switch -regex ($parsd[0])
{
"^Port" {
$myobj = "" | Select-Object Host,PortWWN,NodeWWN,Fabric,Flags,LUN,MFG
$myobj.PortWWN = $parsd[1]
$myobj.Lun = GetTargetLun $srv $myobj.PortWWN
}
"^Node" {$myobj.NodeWWN = $parsd[1]}
"^Fabr" {$myobj.Fabric = $parsd[1]}
"^Flag" {$myobj.Flags = $parsd[1]}
"^Host" {$myobj.Host = $parsd[1]}
"^MFG " {
$myobj.MFG = $parsd[1]
$objCol += $myObj
}
}
}
$objCol
}
function CreateHBAInfoObj{
Param($srv,$wwn)
$objCol = @()
$result = &"$HBACMDPath" "h=$srv" HBAAttrib $wwn
$myobj = "" |Select-Object Host,MFG,SN,Model,ModelDesc,NodeWWN,NodeSymname,
HWVersion,ROM,FW,VenderID,Ports,DriverName,DeviceID,HBAType,
OpFW,SLT1FW,SLT2FW,IEEEAddress,BootBios,DriverVer,KernelVer
foreach($item in $result)
{
$parsd = $item.split([string[]](": "),[system.StringSplitOptions]::RemoveEmptyEntries)
switch -regex ($parsd[0])
{
"^Host" {$myobj.Host = $parsd[1]}
"^Manufacturer" {$myobj.MFG = $parsd[1]}
"^Serial" {$myobj.Sn = $parsd[1]}
"^Model " {$myobj.Model = $parsd[1]}
"^Model Desc" {$myobj.ModelDesc = $parsd[1]}
"^Node WWN " {$myobj.NodeWWN = $parsd[1]}
"^Node Symname" {$myobj.NodeSymname = $parsd[1]}
"^HW" {$myobj.HWVersion = $parsd[1]}
"^Opt" {$myobj.ROM = $parsd[1]}
"^FW" {$myobj.FW = $parsd[1]}
"^Vender" {$myobj.VenderID = $parsd[1]}
"^Number" {$myobj.Ports = $parsd[1]}
"^Driver Name" {$myobj.DriverName = $parsd[1]}
"^Device" {$myobj.DeviceID = $parsd[1]}
"^HBA Type" {$myobj.HBAType = $parsd[1]}
"^Operational" {$myobj.OpFW = $parsd[1]}
"^SLI1 FW" {$myobj.SLT1FW = $parsd[1]}
"^SLI2 FW" {$myobj.SLT2FW = $parsd[1]}
"^IEEE" {$myobj.IEEEAddress = $parsd[1]}
"^Boot " {$myobj.BootBios = $parsd[1]}
"^Driver Ver" {$myobj.DriverVer = $parsd[1]}
"^Kernel " {$myobj.KernelVer = $parsd[1]
$objCol += $myObj}
}
}
$objCol
}
function GetTargetLun{
Param($srv,$wwn)
$objCol = @()
$result = &"$HBACMDPath" "h=$srv" TargetMapping $wwn
[int]$lun = 0
switch -regex ($result)
{
"^SCSI OS Lun" {$lun = $_.split([string[]](": "),[system.StringSplitOptions]::RemoveEmptyEntries)[1].trim()}
}
"{0:x}" -f $lun
}
function Ping-Server {
Param([string]$srv)
if($srv -eq ""){return $false}
$pingresult = Get-WmiObject win32_pingstatus -f "address=’$srv’"
if($pingresult.statuscode -eq 0) {$true} else {$false}
}
Write-Host
if($verbose){$VerbosePreference = "Continue"}
}
Process{
if($_)
{
Write-Host "Getting HBA Info from $_"
if($FullDetail)
{
$MyObject = CreateHBAListObj $_
$HBADetail = $MyObject | %{CreateHBAInfoObj $_.Host $_.PortWWN}
$MyObject | add-Member -Name HBADetail -type NoteProperty -Value $HBADetail -force
$MyObject
}
else
{
$MyObject = CreateHBAListObj $_
$MyObject
}
}
}
End{
if($list)
{
$servers = Get-Content $list
Write-Host "Running HBA Check against Servers in $list"
foreach($server in $servers)
{
if($server -ne "")
{
if(ping-server $server)
{
Write-Host "Getting HBA Info from $server"
if($FullDetail)
{
$MyObject = CreateHBAListObj $server
$HBADetail = $MyObject | %{CreateHBAInfoObj $_.Host $_.PortWWN}
$MyObject | add-Member -Name HBADetail -type NoteProperty -Value $HBADetail -force
$MyObject
}
else
{
$MyObject = CreateHBAListObj $server
$MyObject
}
}
else
{
Write-Host "$Server not Pingable `n" -foregroundcolor RED
}
}
}
}
if($HostName)
{
Write-Host "Running HBA Check against Servers in $HostName"
if(ping-server $HostName)
{
Write-Host "Getting HBA Info from $HostName"
if($FullDetail)
{
$MyObject = CreateHBAListObj $HostName
$HBADetail = $MyObject | %{CreateHBAInfoObj $_.Host $_.PortWWN}
$MyObject | add-Member -Name HBADetail -type NoteProperty -Value $HBADetail -force
$MyObject
}
else
{
$MyObject = CreateHBAListObj $HostName
$MyObject
}
}
else
{
Write-Host "$HostName not Pingable `n" -foregroundcolor RED
}
}
Write-Host
}
tshell :: Nov.08.2007 :: Custom Objects, HowTo, Powershell, Scripting, functions :: No Comments »
Great article. I really, really like the simple way how you create custom object. See my blog entry regarding this http://msgoodies.blogspot.com/2008/01/simple-and-clever-way-to-create-custom.html
Nice. It seems like the ability to create custom objects is essential if PS is going to meet the objective of providing that “last mile” of a management solution. Unforunatly creating them seems to be a rather inelegant proposition. I’ve turned to PSCX’s new-hashobject cmdlet for the task on occasion even though I dislike having to rely on non-native solutions because it complicates distribution. Hopefully V2 will have some better options.