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Im still new to visual basic and im trying to figure out how i can scan my subnet which is: 10.158.0.1 to 10.158.2.254, i want to get the Names of all the computers, the ip of all the computers and a comment (if possible?) I have seen it done in a batch file Here but i dont know how to do it in vb.
Any starting help would be greatly appreciated.
You can ping each of those IP addresses and then make use of the results. My.Computer.Network.Ping method or System.Net.NetworkInformation.Ping class.
the trick is adding one to the host field, especial when the mask is not octet aligned. what is the mask for this subnet?
i have some code that i think i can lift from an app i wrote that
a - produces a range of ip's based on ip and mask
b - produces a list of ip subnets based on two masks (as CIDR)
is anyone interested?
here we go
Code:'place this code in a separate module
'originally written by Dewayne Basnett in VBA - 1997
'converted to VB .Net - 2007
Option Strict On : Option Explicit On
Imports System.Net, System.Text
Module IPStuff
Const IPbrdcst As Long = 4294967295 '255.255.255.255 FF.FF.FF.FF
Dim aIP, aMSK As IPAddress
Dim nIP, nMSK, nNET, nHOST, addrs As Long 'numeric equivalents
Dim nCIDR, CIDR As Integer
Const shBits As Boolean = True 'True = show debug with bits using showBits function
Public Function ipRange(ByVal ipAddr As String, _
ByVal ipMask As String) As List(Of String)
'returns a list of all ip addresse on a given network
'
'ipRange("192.168.3.133", "255.255.254.0") '512 hosts - octet crossing
'
'255.255.254.0 is /23
'List(Of String) - partial output
'192.168.2.0
'192.168.2.1
'192.168.2.2
'...
'192.168.2.254
'192.168.2.255
'192.168.3.0
'192.168.3.1
'...
'192.168.3.253
'192.168.3.254
'192.168.3.255
'note
'first entry in list is THE network number
'last entry in list is the directed broadcast
'
nMSK = IPasNum(ipMask) 'get the Mask as number
CIDR = nCIDR 'get CIDR
nIP = IPasNum(ipAddr) 'get the IP address as number
nNET = IPnetAsNum(nIP, nMSK) 'get THE network number as number
addrs = nNET 'addrs = THE network number as number
nHOST = IPnumOfHosts(nMSK) 'get the number of hosts
If shBits Then
Debug.WriteLine("")
Debug.WriteLine("IP".PadRight(10, " "c) & showBits(nIP) & " " & ipAddr)
Debug.WriteLine("Mask".PadRight(10, " "c) & showBits(nMSK) & " " & ipMask)
Debug.WriteLine("Net".PadRight(10, " "c) & showBits(nNET) & " " & NumToIp(nNET))
Debug.WriteLine("Hosts".PadRight(10, " "c) & showBits(nHOST) & " " & nHOST.ToString)
Debug.WriteLine("CIDR".PadRight(10, " "c) & CIDR.ToString)
'Stop
End If
If nIP < 0 OrElse nMSK < 0 OrElse nNET = 0 OrElse nHOST = 0 Then
Return New List(Of String) 'error
End If
ipRange = New List(Of String)
For x As Long = 0 To nHOST
ipRange.Add(NumToIp(addrs)) 'add host to list
addrs += 1 'increment it
Next
End Function
Public Function IPnets(ByVal ipAddr As String, _
ByVal curCIDR As Integer, _
ByVal newCIDR As Integer) As List(Of String)
'returns a list of sub-nets using any IP in the current network,
'the current mask as CIDR and new mask as CIDR.
'192.168.3.? /23 to /25 - octet crossing
'
'IPnets("192.168.3.128", 23, 25)
'
'List(Of String)
'255.255.255.128
'192.168.2.0
'192.168.2.128
'192.168.3.0
'192.168.3.128
'
Dim curMASK, newMASK, netPlus1 As Long, numOfNets As Integer
nIP = IPasNum(ipAddr) 'get the IP address as number
If nIP < 0 OrElse curCIDR < 2 OrElse curCIDR > newCIDR OrElse newCIDR > 30 Then
Return New List(Of String) 'error
End If
IPnets = New List(Of String)
curMASK = MaskFromCidr(curCIDR) 'convert CIDR's to mask as number
newMASK = MaskFromCidr(newCIDR)
nHOST = IPnumOfHosts(newMASK)
netPlus1 = nHOST + 1 'used to add 1 to the network portion of the ip address
nNET = IPnetAsNum(nIP, curMASK) 'get THE network number as number
numOfNets = CInt(2 ^ (newCIDR - curCIDR)) 'number of networks
IPnets.Add(NumToIp(newMASK)) '<<<<<<<<<<<<<<<<<<<<< first entry in list is the new mask
If shBits Then
Debug.WriteLine("")
Debug.WriteLine("IP".PadRight(10, " "c) & showBits(nIP) & " " & ipAddr)
Debug.WriteLine("Network".PadRight(10, " "c) & showBits(nNET) & " " & NumToIp(nNET))
Debug.WriteLine("Cur. Mask".PadRight(10, " "c) & showBits(curMASK) & " " & NumToIp(curMASK))
Debug.WriteLine("New Mask".PadRight(10, " "c) & showBits(newMASK) & " " & NumToIp(newMASK))
Debug.WriteLine("Plus 1".PadRight(10, " "c) & showBits(netPlus1) & " " & NumToIp(netPlus1))
Debug.WriteLine("Num. Nets".PadRight(10, " "c) & numOfNets.ToString)
'Stop
End If
For x As Integer = 0 To numOfNets - 1
IPnets.Add(NumToIp(nNET))
'to get last address(broadcast) Dim BrdCst as long = nNET Or nHOST
nNET += netPlus1 'add one network number
Next
End Function
Private Function MaskFromCidr(ByVal CIDR As Integer) As Long
'x = 32 - CIDR
'z = (2^x)-1
'return z xor 255.255.255.255
MaskFromCidr = CLng(2 ^ ((32 - CIDR)) - 1) Xor IPbrdcst
End Function
Private Function IPnumOfHosts(ByVal IPmsk As Long) As Long 'a mask for the host portion
'255.255.255.0 XOR 255.255.255.255 = 255 so 0 to 255 is 256 hosts
IPnumOfHosts = IPmsk Xor IPbrdcst 'cacluate the number of hosts
End Function
Private Function IPnetAsNum(ByVal IPnum As Long, ByVal IPmsk As Long) As Long 'extract network from ip address
'192.168.2.113 AND 255.255.255.0 = 192.168.2.0
IPnetAsNum = IPnum And IPmsk 'calculate THE network number
End Function
Private Function IPasNum(ByVal AipAddr As String) As Long 'return -1 on error
If Not IPAddress.TryParse(AipAddr, aIP) Then 'convert string to IP
Return -1 'error
Else
IPasNum = IPtoNum(aIP) 'convert IP to number
If IPasNum = 0 Then
Return -1 'error
End If
End If
End Function
Private Function IPtoNum(ByVal theIP As IPAddress) As Long 'convert IP to number
Dim IPb() As Byte = theIP.GetAddressBytes 'get the octets
Dim theBit As Integer = 31 'work MSb to LSb
Dim addr As Long 'accumulator for address
nCIDR = 0
For x = 0 To 3 'four octets
For y = 7 To 0 Step -1 'with 8 bits each - duh
If (IPb(x) And CByte(2 ^ y)) = CByte(2 ^ y) Then 'if the bit is on
addr += CLng(2 ^ theBit) 'accumulate
nCIDR += 1 'count bits
End If
theBit -= 1 'decrement bit pos
Next
Next
Return addr
End Function
Private Function NumToIp(ByVal theIP As Long) As String 'convert number back to IP
Dim IPb(3) As Byte '4 octets
Dim theBit As Integer = 31 'work MSb to LSb
Dim addr As String 'accumulator for address
For x = 0 To 3 'four octets
For y = 7 To 0 Step -1 '8 bits
If (theIP And CLng(2 ^ theBit)) = CLng(2 ^ theBit) Then 'if the bit is on
IPb(x) += CByte(2 ^ y) 'accumulate
End If
theBit -= 1
Next
addr &= IPb(x).ToString & "." 'add current octet to string
Next
Return addr.TrimEnd("."c)
End Function
Private Function showBits(ByVal aNum As Long) As String
Dim strObits As New StringBuilder
strObits.Append(Convert.ToString(aNum, 2).PadLeft(32, "0"c))
For ix As Integer = 24 To 0 Step -8
strObits.Insert(ix, " ")
Next
showBits = strObits.ToString.Trim
End Function
End Module
is this worthy of the Code Bank?Code:'get local ip address
Dim ipHE As System.Net.IPHostEntry 'declare the structure
Dim myIP As String
Try
ipHE = System.Net.Dns.GetHostEntry("") 'lookup my ip address
If ipHE.AddressList.Length > 0 Then
myIP = ipHE.AddressList(0).ToString
End If
Debug.WriteLine(myIP)
Catch ex As Exception
End Try
'get mask
Dim myMask As String
For Each networkCard As System.Net.NetworkInformation.NetworkInterface _
In System.Net.NetworkInformation.NetworkInterface.GetAllNetworkInterfaces
For Each ip As UnicastIPAddressInformation In networkCard.GetIPProperties().UnicastAddresses
If ip.IPv4Mask IsNot Nothing AndAlso ip.Address.ToString = myIP Then
myMask = ip.IPv4Mask.ToString
End If
Next
Next
OK, i found out that command prompt has a command, Net View. it displays most of the computers on the network (10.158.0.1-10.157.0.254) however i need it to display ALL of the computers (10.158.0.1-10.158.2.254). That's what I'm basically trying to do.
dbasnett, i have looked at your code, and i did not know how to use it and display the info properly, any guidance would be helpful, the subnet mask is 255.255.252.0. I can provide as much info as you need.
if the first address is 10.158.0.1, and the mask is 255.255.252.0 then
the first available address is 10.158.0.1, and the last possible address is 10.158.3.254, not 2.254.Code:Host/Net - 1022 = 1024 - 1 for network# and - 1 for directed broadcast.
Network Broadcast
10.158.0.0 10.158.3.255
IP 00001010 10011110 00000000 00000001 10.158.0.1
Mask 11111111 11111111 11111100 00000000 255.255.252.0
Net 00001010 10011110 00000000 00000000 10.158.0.0
Hosts 00000000 00000000 00000011 11111111 1023
CIDR 22
copy the code i provided to a module.
then insert this into your code
Code:Dim RetStr As List(Of String)
RetStr = ipRange("10.158.0.1", "255.255.252.0")
For nn As Integer = 0 To RetStr.Count - 1
Debug.WriteLine(RetStr(nn)) 'show the results
' My.Computer.Network.Ping(RetStr(nn))
Next
sometimes it is easier to visualize with more bits on
Code:IP 11000000 10101000 11111101 11111110 192.168.253.254
Mask 11111111 11111111 11111100 00000000 255.255.252.0
Net 11000000 10101000 11111100 00000000 192.168.252.0
Hosts 00000000 00000000 00000011 11111111 1023
CIDR 22
@t0rk3y - did this work for you? if it did mark thread resolved.
Yes it did, thank you very much!
u r welcome.