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vbscript reading Cisco switch interfaces


Trying to create a script that will send a 'sh run | b interface' to a Cisco switch. Write the output to an array. Split that array with a vbcr so each line of the config is in a sep elemant of the array.

I have tried to skin the cat many ways and still I am struggling.

Logic in English: Send command to Cisco device Capture the output to an array define expected lines 'This are lines that are required under each 'interface' of the switch Match the 'interface' name and corresponding number and write it to a file. Check under that interface for the specific lines in the expected If it finds it, write the line & ", YES" If it does not find it, write the line & ", NO" Keep doing this until you do not find any more '^interface\s[FG][a-z].+'

Output should look like this: Interface GigabitEthernet 0/2 spanning-tree portfast, YES

This is the sample code that is failing:

'These are the expected line (not being compared in the script below but is my intention to have it compare the matched elements)
Dim vExpectedINT(4)
vExpectedINT(0)  = "spanning-tree portfast"
vExpectedINT(1)  = "switchport access vlan 17"
vExpectedINT(2)  = "switchport mode access"
vExpectedINT(3)  = "ip mtu 1400"    


'objStream.Write "######################################################### " & vbcrlf
'objStream.Write "#                  I N T E R F A C E                    # " & vbcrlf
'objStream.Write "######################################################### " & vbcrlf


nCount = 0
vConfigLines = Split(strResultsINT, vbcr)

Set re = new RegExp
re.Global = False
re.IgnoreCase = True
re.Multiline = False
re.Pattern = "^interface [FG]"

' Regex Ex Definition
Set re2 = new RegExp
re2.Global = False
re2.IgnoreCase = True
re2.Multiline = False
re2.Pattern = "\sspanning-tree\sportfast"

' Regex Ex Definition
Set re3 = new RegExp
re3.Global = False
re3.IgnoreCase = True
re3.Multiline = False
re3.Pattern = "ip\smtu\s1400"

Set re4 = new RegExp
re4.Global = False
re4.IgnoreCase = True
re4.Multiline = False
re4.Pattern = "!"

' Compares the information
x = 1
Do While x <= Ubound(vConfigLines) - 1 do 
    MsgBox chr(34) & strLine & chr(34)
    If re.Test(vConfigLines(x)) Then
        ' Write data to not expected section
        x=x+1
        do
            If ! re4.Test(vConfigLines(x)) Then
                MsgBox vConfigLines(x)
                'objStream.Write vConfigLines(x) & vbcr
                elseif re2.Test(vConfigLines(x)) Then
                MsgBox vConfigLines(x)
                elseif re3.Test(vConfigLines(x)) Then
                MsgBox vConfigLines(x)
            else
                exit do
            end if
            x=x+1
        loop
        end IF
   End If
Loop    

This is a sample of the vConfigLines output:

There could be 48+ port per switch.

interface FastEthernet1/0/1
 switchport access vlan 127
 switchport mode access
 switchport voice vlan 210
 srr-queue bandwidth share 10 10 60 20
 srr-queue bandwidth shape 0 3 0 0
 priority-queue out 
 mls qos trust cos
 auto qos voip trust 
 spanning-tree portfast
!
interface FastEthernet1/0/2
 switchport access vlan 127
 switchport mode access
 switchport voice vlan 210
 srr-queue bandwidth share 10 10 60 20
 srr-queue bandwidth shape 0 3 0 0
 priority-queue out 
 mls qos trust cos
 auto qos voip trust 
 spanning-tree portfast
!
interface FastEthernet1/0/3
 switchport access vlan 127
 switchport mode access
 switchport voice vlan 210
 srr-queue bandwidth share 10 10 60 20
 srr-queue bandwidth shape 0 3 0 0
 priority-queue out 
 mls qos trust cos
 auto qos voip trust 
 spanning-tree portfast

Solution

  • When facing a difficult and complex task, just follow these rules:

    Divide the task in independently solvable subproblems
      getting the info from Cisco
      processing the resulting file
        gather interesting info
        output
    
    Concentrate on the difficult subtask(s)
      processing the resulting file
    
    Solve a simplified but generalized version of (each) subtask using handmade data
    for easy testing
      You have items and are interested in whether they (don't) have given properties
    

    Data to play with:

    Item 0 (both props)
     prop_a
     prop_b
    !
    Item 1 (just b)
     prop_b
    !
    Item 2 (a only)
     prop_a
    !
    Item 3 (none)
    !
    Item 4 (irrelevant prop)
     prop_c
    !
    Item 5 (Richy)
     prop_c
     prop_b
     prop_a
    !
    Item 6 (Junky)
     junk
    
     prop_b
     whatever
    
    !
    #Item 7 (Nasty)
    # prop_a_like_but_not_prop_a
    # prop_b
    #!
    
    Keep it simple
      don't do more than absolutely necessary
      don't use variables/components you can do without
    

    So let's start:

    You have to deal with a text file (lines). So don't do more than

      Dim tsIn : Set tsIn = goFS.OpenTextFile("..\data\TheProblem.txt")
      Dim sLine
      Do Until tsIn.AtEndOfStream
          sLine = Trim(tsIn.ReadLine())
          If "" <> sLine Then
          End If
      Loop
      tsIn.Close
    

    90 % of the code using Split on .ReadAll is just fat. Yes, it's Do Until tsIn.AtEndOfStream and not Do While tsIn.AtEndOfStream = False. No Set tsIn = Nothing, please.

    The data is organized in blocks (Item n ... !), so make sure you recognize the parts and know what to do when finding them:

      Dim tsIn : Set tsIn = goFS.OpenTextFile("..\data\TheProblem.txt")
      Dim sItem  : sItem    = "Item"
      Dim sEnd   : sEnd     = "!"
      Dim sLine
      Do Until tsIn.AtEndOfStream
          sLine = Trim(tsIn.ReadLine())
          If "" <> sLine Then
             Select Case True
               Case 1 = Instr(sLine, sItem)
                 WScript.Echo "Begin, note item (name)"
               Case 1 = Instr(sLine, sEnd)
                 WScript.Echo "End, output info"
                 WScript.Echo "----------"
               Case Else
                 WScript.Echo "Middle, gather info"
             End Select
          End If
      Loop
      tsIn.Close
    

    output:

    Begin, note item (name)
    Middle, gather info
    Middle, gather info
    End, output info
    ----------
    Begin, note item (name)
    Middle, gather info
    End, output info
    ----------
    ...
    

    For each item the output should be:

    name, property, yes|no
    

    The easiest way to do that is

    WScript.Echo Join(aData, ", ")
    

    Joining beats concatenation, especially if you want to set/manipulate the parts independently and/or to pre-set some of them in the beginning.

      Dim aData  : aData    = Array( _
          Array( "Item?", "prop_a", "NO") _
        , Array( "Item?", "prop_b", "NO") _
      )
      Dim sLine, aTmp, nIdx
      Do Until tsIn.AtEndOfStream
          sLine = Trim(tsIn.ReadLine())
          If "" <> sLine Then
             Select Case True
               Case 1 = Instr(sLine, sItem)
                 aTmp = aData
                 For nIdx = 0 To UBound(aTmp)
                     aTmp(nIdx)(0) = sLine
                 Next
               Case 1 = Instr(sLine, sEnd)
                 For nIdx = 0 To UBound(aTmp)
                     WScript.Echo Join(aTmp(nIdx), ", ")
                 Next
                 WScript.Echo "----------"
               Case Else
                 WScript.Echo "Middle, gather info"
             End Select
          End If
      Loop
      tsIn.Close
    

    The output

    ...
    Item 3 (none), prop_a, NO
    Item 3 (none), prop_b, NO
    ...
    

    shows that by setting sensible defaults (NO), this version of the script deals correctly with items having none of the interesting properties.

    So lets tackle the middle/Case Else part:

       Case Else
         For nIdx = 0 To UBound(aTmp)
             If 1 = Instr(sLine, aTmp(nIdx)(1)) Then
                aTmp(nIdx)(2) = "YES"
                Exit For
             End If
         Next
    

    output now:

    Item 0 (both props), prop_a, YES
    Item 0 (both props), prop_b, YES
    ----------
    Item 1 (just b), prop_a, NO
    Item 1 (just b), prop_b, YES
    ----------
    Item 2 (a only), prop_a, YES
    Item 2 (a only), prop_b, NO
    ----------
    Item 3 (none), prop_a, NO
    Item 3 (none), prop_b, NO
    ----------
    Item 4 (irrelevant prop), prop_a, NO
    Item 4 (irrelevant prop), prop_b, NO
    ----------
    Item 5 (Richy), prop_a, YES
    Item 5 (Richy), prop_b, YES
    ----------
    Item 6 (Junky), prop_a, NO
    Item 6 (Junky), prop_b, YES
    ----------
    

    But what about Nasty:

    #Item 7 (Nasty)
    # prop_a_like_but_not_prop_a
    # prop_b
    #!
    

    The simple Instr() will fail, if one property name is a prefix of another. To prove that starting simple and add complexity later is good strategy:

      Dim sFSpec : sFSpec   = "..\data\TheProblem.txt"
      WScript.Echo goFS.OpenTextFile(sFSpec).ReadAll
      Dim tsIn   : Set tsIn = goFS.OpenTextFile(sFSpec)
      Dim sItem  : sItem    = "Item"
      Dim sEnd   : sEnd     = "!"
      Dim aData  : aData    = Array( _
          Array( "Item?", "prop_a", "NO") _
        , Array( "Item?", "prop_b", "NO") _
      )
      Dim aRe    : aRe      = Array(New RegExp, New RegExp)
      Dim nIdx
      For nIdx = 0 To UBound(aRe)
          aRe(nIdx).Pattern = "^" & aData(nIdx)(1) & "$"
      Next
      Dim sLine, aTmp
      Do Until tsIn.AtEndOfStream
          sLine = Trim(tsIn.ReadLine())
          If "" <> sLine Then
             Select Case True
               Case 1 = Instr(sLine, sItem)
                 aTmp = aData
                 For nIdx = 0 To UBound(aTmp)
                     aTmp(nIdx)(0) = sLine
                 Next
               Case 1 = Instr(sLine, sEnd)
                 For nIdx = 0 To UBound(aTmp)
                     WScript.Echo Join(aTmp(nIdx), ", ")
                 Next
                 WScript.Echo "----------"
               Case Else
                 For nIdx = 0 To UBound(aTmp)
                     If aRe(nIdx).Test(sLine) Then
                        aTmp(nIdx)(2) = "YES"
                        Exit For
                     End If
                 Next
             End Select
          End If
      Loop
      tsIn.Close
    

    output:

    Item 0 (both props)
     prop_a
     prop_b
    !
    Item 1 (just b)
     prop_b
    !
    Item 2 (a only)
     prop_a
    !
    Item 3 (none)
    !
    Item 4 (irrelevant prop)
     prop_c
    !
    Item 5 (Richy)
     prop_c
     prop_b
     prop_a
    !
    Item 6 (Junky)
     junk
    
     prop_b
     whatever
    
    !
    Item 7 (Nasty)
     prop_a_like_but_not_prop_a
     prop_b
    !
    
    Item 0 (both props), prop_a, YES
    Item 0 (both props), prop_b, YES
    ----------
    Item 1 (just b), prop_a, NO
    Item 1 (just b), prop_b, YES
    ----------
    Item 2 (a only), prop_a, YES
    Item 2 (a only), prop_b, NO
    ----------
    Item 3 (none), prop_a, NO
    Item 3 (none), prop_b, NO
    ----------
    Item 4 (irrelevant prop), prop_a, NO
    Item 4 (irrelevant prop), prop_b, NO
    ----------
    Item 5 (Richy), prop_a, YES
    Item 5 (Richy), prop_b, YES
    ----------
    Item 6 (Junky), prop_a, NO
    Item 6 (Junky), prop_b, YES
    ----------
    Item 7 (Nasty), prop_a, NO
    Item 7 (Nasty), prop_b, YES
    ----------