I am trying to create scripts/services that allow for waking PCs in a windows domain via WOL. Now i want to give the user the option to select an AD container as a starting point for the waking of PCs contained within. My initial thought is using DHCP as a repository to query for MAC addresses given the hostnames (which i can easily enough pull from AD given the container).
Is there a way to programmatically query the DHCP service/server, passing hostnames and recover the associated MAC addresses?
Or, is there a better/easier way to solve my problem?
This is a little bit wacky it seems that there's no way to query the DHCP server programmatically. Thanks cottsak for asking the question. I understand that the DHCP protocol doesn't have such a query, but I thought mayb the executable from Microsoft might have some way you can address it from the command line. I haven't heard anybody anywhere say that there is no such case, but it must be so.
WHOA, wait a minute... I think I found what we're looking for: NETSH. cf:
http://social.technet.microsoft.com/Forums/en/ITCG/thread/afb4be16-09bd-4260-b515-8323d85d4ccb
Where it says if you open a command prompt on the DHCP server you can run this command:
netsh dhcp server scope 192.168.1.0 show clients
and get a report such as this:
10.10.98.53 - 255.255.255.0 -00-0c-29-02-a4-09 - NEVER EXPIRES -D
10.10.98.54 - 255.255.255.0 - 00-22-19-10-29-75 -1/21/2012 8:39:25 AM -D
Yippeee! Thanks for the thread!! If it wasn't for this one, I enver would have narrowed my search to technet adn found that one.
Try dhcpexim.exe from microsoft.
or, if you prefer using pure C. DhcpEnumSubnetClientsV4
No problem; because all of the machines are in your domain you can put together a VBScript that will get the MACAddress(es) from the local machine and store it as an attribute of the computer object in Active Directory.
Here's a quick hack on how to do that (save this as a .vbs-file):
Option Explicit
Const ADS_PROPERTY_UPDATE = 2
Const COMPUTERLOCATION = "ou=Member Servers,dc=yourdomain,dc=com"
Const ATTRIBUTETOUSE = "otherTelephone"
Dim wshNetwork, strComputerName
Set wshNetwork = WScript.CreateObject("WScript.Network")
strComputerName = wshNetwork.ComputerName
Dim objWMIService, colNetCards, objComputer, objNetCard
Set objWMIService = GetObject("winmgmts:\\" & strComputerName & "\root\cimv2")
Set colNetCards = objWMIService.ExecQuery("Select * From Win32_NetworkAdapterConfiguration Where IPEnabled = True")
Set objComputer = GetObject("LDAP://cn=" & strComputerName & "," & COMPUTERLOCATION)
For Each objNetCard in colNetCards
objComputer.PutEx ADS_PROPERTY_APPEND, ATTRIBUTETOUSE, Array(objNetCard.MACAddress)
objComputer.SetInfo
Next
Because your clients aren't all in the "Member Servers" OU above you'll need to modify the above script to include a directory search for the strComputerName do get the COMPUTERLOCATION.
When you have a working script, ask your domain administrator to put the script as a start-up script targetting the computers you need to monitor; that way it'll execute whenever a computer boots up. You can also run the script as a scheduled task to get your data from any clients that haven't rebooted or use psexec or some other way you can think of to get the data immediately. Or you can rewrite the script entirely to remote connect to all of your machines and get the data that way (which might not be possible due to local firewalls). Or you could write a small .NET console application which does the same thing, it's up to you...
Also, although there is a networkAddress-attribute defined for computer objects; by default the computer object itself does not have access to write to this property. Because start up-scripts run in the context of the SYSTEM account on the particular machine the easiest thing is to use an attribute that the computer object (SELF) has write access to. The otherTelephone-attribute is multivalued and part of the Personal-Information Property Set which all computer objects has write access to by default. If you want to use the networkAddress-attribute you need to set explicit write access to that attribute for all of your computers.
Also you need to bear in mind that storing the the MAC address in Active Directory means that all of the users in your domain will have read access to it which in turn might possibly (depending on your environment) pose a small security risk.
To do it the way the network does.
Grab SharpPcap (Pcap wrapper for C#) and WinPcap (Windows) or libpcap (*nix). Write an application that creates SNMP packets to query the ARP table on the router.
Note: The ARP (Address Resolution Protocol) table is the table containing the mapping of IP address to MAC address.
I've been thinking about implementing an example that does this lately but I don't have one to show yet. Once I do, I'll make sure it gets added to the SharpPcap examples found in the project's source tree.
You can't do that with DHCP. DHCP attributes IP from MAC, not the other way around.
ARP is what converts IP into MAC but it's the machine itself that answers ARP requests so if it's off it's obviously not gonna answer ...
I suggest you store the MAC in your AD directly (I guess AD supports custom attributes ?)
you need to use arp to get a mac adress and doing so In C is a long process.
Mac adresses are hard coded, so if you have X computers go and get X mac addresses and tie them to the AD.
Note that the computer will have to be on to request its mac address.
Finding MAC address from IP address
Yeah dun worry about it, you can pull this info directly from DHCP if the PC has a lease.
Know how you right click and add a reservation in DHCP?
Look in DHCP for the 'unique ID'. It's the MAC address, sans the colons.
Related
I want to connect to a ActiveDirectory using c#.
I need to be able to connect to an DC which I can only resolve using an IP Address (which I have).
The next step is to find a computer in the DC address leases to resolve the IP address of a computername entered by a user.
Can someone give me a heads up?
I should be using
DirectoryEntry directoryEntry = new DirectoryEntry("LDAP://DC-IpAddress");
directoryEntry.Path = "LDAP://(What should I enter here for "Address Leases"?);
then I need a returned value which gives me the IP-Address of target Computer.
Hope you folks can help me out a bit.
FYI: The DHCP Server is installed on the target DC. just in case ;)
in this link VB project which is contains in the forth section a method that Listing all computers in the Active Directory .. may it helpful for you
http://www.codeproject.com/Articles/19689/Working-with-Active-Directory-in-VB-NET
i am looking for class that can show me all the Network properties of machine:
Ip's,
Default Gateway,
Mac Address,
Default Gateway,
Adapter Speed,
etc..
thanks
You can get this information using the NetworkInformation class.
Getting Information about IP addresses is demonstrated here: IPInterfaceProperties
To get Link speed, you can need to use Windows Management Interfaces (WMI). As a starting point for your research, you'll want to run this WMI query:
SELECT NdisLinkSpeed FROM MSNdis_LinkSpeed
Then convert it to MB/s with:
SpeedInMbps = NdisLinkSpeed / 10000
I need to get a list of all the network names that the user is connected to and the IP address of the computer on that network. I can get a list of network names using NetworkInformation.GetConnectionProfiles() and I can get a list of IP addresses using NetworkInformation.GetHostNames(), but I cannot figure out how to associate the two lists. I thought it would be through the NetworkAdapters but the IDs for those are different between the two different calls.
Does anyone know how to do this?
UPDATE: Just to clarify, I'm asking how to do this in a Metro app on Windows 8.
UPDATE 2: It turns out it was a bug in Release Preview. Now that we've switched to RTM everything worked without a single change to the existing code.
EDIT: Just found this... Query Local IP Address Looks like a cleaner way. Take your pick...
I'm gonna take a stab... hopefully gets you close. I only have one adapter that is connected on my test machine, but I think (hope) this would work in a machine with multiple adapaters.
// Get all profiles
var profiles = NetworkInformation.GetConnectionProfiles();
// filter out profiles that are not currently online
var connected = from p in profiles where p.GetNetworkConnectivityLevel() != NetworkConnectivityLevel.None select p;
// find all hosts
var hosts = NetworkInformation.GetHostNames();
// find hosts that have an IP Address
var online = from h in hosts where h.IPInformation != null select h;
// Now loop there each online connection and match network adapter ids with hosts
foreach (var c in connected)
{
var matches = from o in online where o.IPInformation.NetworkAdapter.NetworkAdapterId == c.NetworkAdapter.NetworkAdapterId select o;
}
The only problem here is that a single physical adapter will actually show up once for its IPv4 address and once for its IPv6 address. You will have to go the extra step and correlate them together. Hopefully this is what you are looking for.
well, I don't know about c# or the .net framework, but from a windows command prompt, the command netstat -f is what you need. Perhaps you could parse that.
Update
I think I understand what you need. If you have a list of IP addresses, you can convert them to hostnames with Dns.GetHostEntry
Have a look on this article, which discusses the issue in C#.
I'm finally set up to be able to work from home via VPN (using Shrew as a client), and I only have one annoyance. We use some batch files to upload config files to a network drive. Works fine from work, and from my team lead's laptop, but both of those machines are on the domain. My home system is not, and won't be, so when I run the batch file, I get a ton of "invalid drive" errors because I'm not a domain user.
The solution I've found so far is to make a batch file with the following:
explorer \\MACHINE1
explorer \\MACHINE2
explorer \\MACHINE3
Then manually login to each machine using my domain credentials as they pop up. Unfortunately, there are around 10 machines I may need to use, and it's a pain to keep entering the password if I missed one that a batch file requires.
I'm looking into using the answer to this question to make a little C# app that'll take the login info once and login programmatically. Will the authentication be shared automatically with Explorer, or is there anything special I need to do? If it does work, how long are the credentials cached?
Is there an app that does something like this automatically?
Unfortunately, domain authentication via the VPN isn't an option, according to our admin.
EDIT: If there's a way to pass login info to Explorer via the command line, that would be even easier using Ruby and highline.
EDIT: In case anyone else has the same problem, here's the solution I wound up using. It requires Ruby and the Highline gem.
require "highline/import"
domain = ask("Domain: ")
username = ask("Username: ")
password = ask("Password: ") { |q| q.echo = false }
machines = [
'\\MACHINE1\SHARE',
'\\MACHINE2\SHARE',
'\\MACHINE3\SHARE',
'\\MACHINE4\SHARE',
'\\MACHINE5\SHARE'
]
drives = ('f'..'z').to_a[-machines.length..-1]
drives.each{|d| system("net use #{d}: /delete >nul 2>nul"); }
machines.zip(drives).each{|machine, drive| system("net use #{drive}: #{machine} #{password} /user:#{domain}\\#{username} >nul 2>nul")}
It'll figure out how many mapped drives I need, then start mapping them to the requested shares. In this case, it maps them from V: to Z:, and assumes I don't have anything shared with those drive letters.
If you already have an Explorer window open to one of the shares, it may give an error, so before I ran the Ruby script, I ran:
net use * /delete
That cleared up the "multiple connections to a share not permitted" error, and allowed me to connect with no problems.
You could create a batch file that uses "NET USE" to connect to your shares. You'd need to use a drive letter for each share, but it'd be super simple to implement.
Your batch file would look like this:
net use h: \\MACHINE1 <password> /user:<domain>\<user>
net use i: \\MACHINE2 <password> /user:<domain>\<user>
net use j: \\MACHINE3 <password> /user:<domain>\<user>
UPDATE
Whether the connection remains or not depends upon what you specified for the /persistent switch. If you specified yes, then it will attempt to reconnect upon your next logon. If you specified no then it won't. The worrying this is the documentation says that it defaults to the value that you used last!
If you specified no, the connection will remain until you next reboot. If you drop your VPN connection the drive would be unavailable (but if you reconnect to the VPN the drive should be available as long as you haven't removed it).
I don't know of a way to use it without mapping to a drive letter, the documentation would lead you to believe that it isn't possible.
I understand your problem, that you're just trying to give explorer the correct credentials so it stops nagging you with login boxes. Using mapped drives though not perfect will at least alleviate your pain.
to pass credential by command line to the explorer you should take a look into the command net use
Use API WNetAddConnection2() via P/Invoke.
Greetings,
I need a way (either via C# or in a .bat file) to get a list of all the computers on a given network. Normally, I use "net view", but this tends to work (from my understanding) only within your domain. I need the names (or at least the IP Addresses) of all computers available on my network.
Being able to get all computers on a domain that isn't mine (in which case I'd use WORKGROUP, or whatever the default is) would also work.
Nmap is good for this - use the -O option for OS fingerprinting and -oX "filename.xml" for output as xml that you can then parse from c#.
A suitable commandline would be (where 192.168.0.0/24 is the subnet to scan):
nmap -O -oX "filename.xml" 192.168.0.0/24
leave out the -O if you aren't interested in guessing the OS - if you just want a ping sweep use -sP, or read the docs for the myriad other options.
To expand on what Unkwntech has said -
You can also do a "broadcast" ping to avoid having to ping each IP address individually.
Immediately after than you can use "arp" to examine the ARP cache and get a list of which IP addresses are on which MAC address.
Ping everything in the rage, then you can get netbios info from the systems that respond to identify it's name.
In one of my web app I used the NetApi32 function for network browsing.
Code:
http://gist.github.com/11668