Management of a DHCP client in a remote unknown network

Dear all,
Here is my problem :
I have the network A with a DHCP Server.
Network A knows the network B only with its NATed addresses
In DHCP Server (which is on a Solaris machine) the remote client is configured with NATed informations.
In network B I have a client.
Network B knows the network A only with its NATed addresses
The ip helper-adress is set to NATed address of the DHCP Server.
At the client power up, all works fine but the client receive all its NATed informations so it's IP, netmask and gateway addresses are wrong.
I would like to know if the DHCP relay can modify some information in the DHCP-OFFER packets.
Thanks for your help.
Br,
Jean-Yves ANDREOLETTI

Hi Jean-Yves,
can I add some options on my clients from the DHCP master server.
This is, in general, impossible. DHCP protocol essentially lacks any features in which DHCP servers can cooperate, share the address leases or synchronize the configuration options handed out to clients. Indeed, the entire DHCP protocol focuses exclusively on the client-server communication, and there are no provisions for server-server information exchange.
If your router was obtaining an IP address from the DHCP server itself (i.e. if one of its interface was configured with ip address dhcp) then you could use the import all command in the DHCP pool on the router, causing the router to obtain all DHCP options not explicitly specified in the pool from the DHCP server. However, this scenario is more applicable to dialout solutions, and I do not think it is suited to your network.
Apart from this, I am not aware of any method that would allow you to merge a selected set of settings on a local DHCP server with another settings from a master DHCP server. I am sorry to disappoint you.
Best regards,
Peter

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All Windows Updates installed
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Reset Winsock
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WRT54G v7 - DHCP Client List problem

Hi all,
I have the WRT54G v.7 - firmware ver.7.00.8.
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Solved!
Go to Solution.

Reboot your computer and it will receive a new IP address from the router.
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Acces dhcp client list remote

Dear forum
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virknuforfanden wrote:
I would like to keep an eye on my wireless network. I know this is possible from the airport util. by looking at the dhcp client list. however i would like to do this remote as well - while i'm at work or similar.
If you look at the AirPort Utility Advanced panel, Logging & Statistics tab, you'll see a setting for "Allow SNMP over WAN". SNMP is "Simple Network Management Protocol". That's supposed to enable the type of thing you want to do. Beyond that I can't help you, as I've never worked with SNMP software.

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With reference to your post I would like to know that does all the client devices on your network runs on DHCP or some of them have static IP address as well? The devices which are running on static IP address will not be displayed in the DHCP client table.
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DHCP Client will not work on a WLAN 4402

Wireless Scenario
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I have tried the internal DHCP server on the controller, and although the wireless client gets a 10.29.64.x address it will not communicate with the default gateway or the rest of the network.
The only thing that works is creating a scope on the 10.71.50.x network. The client then gets an address and functions normally.
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How-to: Check DHCP clients on the LAN ports??

Hi,
I can manage the DHCP clients on the wifi. But not on the LAN.
Can anyone let me know where in the AirPort Utility?
regards,

I have more info on this topic as I'm an interested party and would LOVE to see this work right one day....
The clients pop-up window does show physically connected clients and wireless clients, as well as clients physically connected to wireless bridges (check). Most of them. I have two wireless bridges with manually assigned ips outside the DHCP range and no port filtering. Only one of them shows up in this list, and I'm not sure why it does (not DHCP but has a reservation). Also - my linux host shows up, but the VM running inside it does not. Perhaps the virtual bridged adapter is confusing somebody up in the sealed time capsule but they get unique ip addys and are all accessible so the server must be seeing unique MACs (not to be confused with Macs)
I think it was a good try to provide a client view, its just buggy and feature weak.
I'm actually considering scrapping the airport as a router altogether - it doesn't even do local dns if you happen to have alot of clients on your home network, nor does it really support a separate local dns server because you cant tell DHCP what to send your clients. They decide for you so you dont fall down and bump your knee. Meh. And please - dont recommend I use Bonjour to Resolve Names on a Network...we run more than OSX here the whole world uses DNS and we should be able to too..

2012 R2 RDS Shadowing from Server Manager - how to view client computer names

Hello,
I have a 2012R2 RDS session based deployment. We have a few generic user accounts for a production environment where a group of users uses the same username to start multiple RDS sessions. This creates a bit of a challenge when support has to shadow one
of those sessions because they all appear with the same name: domain\username. The Connections pane in RDS (Server manager) does not list client computer name, which would be the distinguishing factor. The old version of the RDS console (remote
desktop manager) had this information. Citrix appears to have it as well. Is there a way around this limitation in 2012R2 Server Manager?
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Hi,
As far as I know, there are two ways.
1. Use the Task Manager. In the Users Tab, you can see the client name.
http://social.technet.microsoft.com/Forums/en-US/1d571c01-69ff-4508-af0f-d7eeecd806b6/forum-faq-how-to-manage-rds-user-connections-and-processes-in-a-rds-2012-deployment?forum=winserverTS
2. Use the Terminal Services PowerShell Module. With the Get-TSSession in PowerShell, we can get the detailed information.
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DHCP client does not work poperly after systemd and Gnome 3.6 upgrade

Upgraded my system today from Gnome 3.4 to 3.6 (and systemd was updated as well), and since then acquiring an IP address using DHCP does not work anymore.
I am using IPv4 only internally, but neither dhclient or dhcpcd manages to get an IPv4 address.
It seems like IPv6 is priority one, and beacuse there is no IPv6 DHCP server available NetworkManager aborts the whole setup process.
To make sure that IPv6 should not be considered, I have changed "method" in NetworkManager to "Ignore" for IPv6.
I have also tried to downgrade NM to 0.9.6.0 from 0.9.6.4 (since that version works on another, not upgraded, machine), without any result.
Also switched dhclient to dhcpcd, without any result.
The machine is a "pure" systemd machine.
DHCP works for other devices in the network.
Versions:
systemd 195-2
NetworkManager 0.9.6.4
isc-dhclient-4.2.3-P2
I have no issues on a system where following versions are running:
systemd 189-4
NetworkManager 0.9.6.0
dhcpcd 5.6.2
Log: http://pastebin.com/2wMC0JLe

Think I have identified the issue now.
Neither dhcpcd or dhclient is sending the host name properly to the DHCP server anymore. I had an IP address reserved in the DHCP server for my host and after deleting this reservation my host is able to acquire an IP (dynamic) address. The reserved static address could never be acquired.
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I've searched the forum and similar messages and other routers mention that a firmware update will fix the problem where not all dhcp connections show up in the status/local networks/dhcp clients table.
I have WRT54G hardware version 6, firmware v 1.00.06.
I've looked at the firmware updates and no mention of this problem appears. I don't want to needlessly update my firmware.
Does anyone know if this problem has been fixed in the latest firmware?

More info:
It seems that the linux box (ubuntu 7.04) is using the bootp protocol, not full dhcp. From some reading of the rfc's it seems that dhcp is an enhancement to bootp, and it is valid for clients to request an ip address from a dhcp server (the protocols use the same ports etc.).
However, bootp does not deal with a lease and since the dhcp client tables list a lease time, I am guessing that this different way of getting an ip address is what is messing with the router.
On the one hand, it could be said that since it's not a full dhcp client, the router would be technically correct to not show it in the client list.
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? Retrieving DHCP Client Table ?

I apologize in advance if this has been addressed in the forums, I have searched and looked manually but to no avail as yet. Please advise to url if Thread exists. TYVMIA
My DHCP router:
BEFW11S4 v4, f/w v1.52.02
The DHCP-disabled router (as hub?):
BEFSR41 v2, f/w v1.45.11
My DHCP clients:
3 Windows XP Home - based PCs
1 XBox (original)
1 XBox 360 "Elite"
1 PS3
1 Brother 420-CN MFC via LAN
My issue:
I've managed to "lose" my DHCP Client Table via the router's web interface. I'm referring specifically to the Table which is accessed through the "Status --> Local Network" tab of the interface. Actually, the Table is still accessible but I can't use it to show me the information for the active IP clients. I think I lost this information when I mistakenly deleted the active IP clients from the table. (I misunderstood the function of the "Delete" execution of the Table.)
My question:
How do I re-quip the router's software so that I can access/read the information about the devices on my network.
My motivation:
Troubleshooting device connectivity. Specifically, 'Net access for the gaming consoles is interrupted, though all other devices can fully access the 'Net without interruption of services.
Again, thank you in advance very much for any insight, advice, suggestions, or guidance regarding my situation. I am glad to offer any other technical information as requested. Have a blessed day : )
Scott
sunfoot
Message Edited by sunfoot on 07-23-2007 11:36 PM

not quite sure abt getting back the information on the DHCP client table ... may be you could resetting and reconfiguring the router and check whether this makes any difference..
regarding the interruption in the internet connection while playing games ... i have a question for you....does the internet connection drop on the computers while playing the gaming consoles ?? if it is dropping then its the bandwindth issue as online gaming need a lot of bandwidth ..

DHCP Client List doesn't list VPN Users - 10.5.4

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When I had Tiger 10.4.11 running, it would usually list every DHCP client on the system. Including those outside the subnet in the VPN range. Now that we are running Leopard Server 10.5.4, client no longer appear in the DHCP client list under server manager.
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DHCP range; 192.168.2.1 - 192.168.2.147 - subnet- 255.255.255.0
VPN range; 192.168.2.148 - 192.168.2.255
I noticed I had to change DHCP clientIDs and change the printer machine names to get them to show up in the DHCP client list.
Even if I modify the DHCP client ID on the VPN users machines and change the machine name, I still can't get anything to show up.
Does the DHCP client list no longer list the VPN users?
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ATF

Hello,
An additional note. When I VPN into the server, I no longer can access the clients via ARD like I used to under Tiger.
Seems to gel that if the DHCP server and can see local clients over the gigabit network, but can't see the VPN clients that I also can't see the internal clients via VPN.
AGGGH.
Suggestions?
ATF

DHCP Clients Bandwidth Throughput?

Hi, I've set up a Leopard Server as DHCP/NAT. Everything is working perfectly. Only thing is I'd like to monitor the bandwidth usage of the DHCP clients, since we are experiencing some bottlenecks due to exhaustive bandwidth usage by some clients from time to time. I've already tried ntop but it was a bit of an overkill.
Is there something like a script for the CLI that outputs something like this:
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etc.
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Chris
Message was edited by: criuz

You can see what's hitting the NICs on the server (network traffic either starting at or ending at or traversing a dual-NIC server), but DHCP is not (AFAIK) relevant here. You'll only see the traffic that traverses the local host, or (depending on what widget and what role you're monitoring) the IP router. (You specifically mention "between" clients, and that traffic -- on a typical WiFi or LAN with a typical subnet-- can effectively be direct; it won't necessarily traverse any routers.)
DHCP is how client hosts get (managed) IP addresses, and -- once the client hosts have received addresses -- then DHCP is basically (save for address renewals) out of the way.
Except when the NIC is operating in promiscuous mode or when it receives a packet addressed to one of the MAC (the network "MAC", and not the computer named "Mac") addresses it is listening for, the NIC and the host don't really pay attention to what traffic is passing by out on the LAN.
There might well be a way of extracting this per-host traffic data via SNMP (SNMP does have substantial data available, I've simply not confirmed that the per-host network traffic is one of the gaziilions of data points that are monitored), but that'll require some software for retrieval and consolidation of the data.
As Camelot mentions, aggregate network traffic is best monitored from a (managed) network switch or from a network probe. A promiscuous-mode host can be used, but packet traffic can really load a server; managed switches make better and more economical network probes.
GbE (Gigabit Ethernet) can be a cheap upgrade, too, assuming you're on Cat5enh wiring or better. (There are two Cat5e specs around. One does have a GbE rating (Cat5enh), and the other doesn't.) And low-end managed switches aren't all that expensive these days.

I want to reserve a static IP address on my Airport extreme. What is the difference between reserving by MAC Address and DHCP Client ID?

I want to understand the differences in the way you can reserve a static address for a device on the network. I had previously set the device itself to an address and then reserved it with DHCP Client ID, which I thought was just the devices static addresss. I'm not sure if this was in fact correct or just happend to work. I know what a MAC address is, but I'm not really sure what the DHCP Client ID is. So it would be great if someone could clarify it, and the difference between reserving address by MAC Address or DHCP Client ID.

A MAC address is a unique identification consisting of letters and numbers in a form that looks like this:
xx:xx:xx:xx:xx:xx
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Management of a DHCP client in a remote unknown network

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