View Full Version : DHCP Client, How do I see/get their MAC
I run a few of the Star-OS boxes. Most of my DHCP is done via Cisco except for the Star-OS boxes which I run DHCP on for the clients connected to said box. The probelm is that unlike using my Cisco Routers, I can't find any way to see what is going on with the AP. I can tell that a customer has ip address 172.16.1.xx but I can't see what the mac address is so I can set it up so they have the same ip address each time....which is easy......IF i knew the mac address.
Anyone know how to look this up in the OS?
Tim D
To get the MAC address of your client, you can either look it up in your Access Point association table (Function keys F1 to F8), or the systems ARP table. You can find the ARP table using menu:
advanced->system reports->view system information
If the AP is bridged, then you will need to look at the ARP table on the router behind the bridge.
Thanks!
Well one time on one AP only I was able to see the DHCP Window with the MAC addresses associated with each request. Now for whatever reason not only does the f1 key not bring that up but the arp table only lists the MAC address of the bridge the customer is on and not the MAC address of the computer or router on their end actually making the request.
As I need to control the bandwidth in a central location I am using another product on the main site. I need to control this bandwidth using the ip address of the customers computer, i still need to find that mac address and can't see it in the Star-OS
Any suggestions anyone?
Tim D
lonnie
09-29-2003, 01:21 PM
Are you bridged on the StarOS box? If you are then it will not have entries in the ARP table as it simply passes traffic.
Pseudo Bridges hide MAC addresses, and any unit in Infrastructure is a pseudo bridge. The reason for this is quite simple - no bridge mode was ever specified for Infrastructure, only AP and AdHoc mode (modified AP mode). Clients are meant to connect to one user or have a router to connect to multiple users.
You could try WDS mode instead of Infrastructure as it is a true bridge and thus will pass packets intact without any mods to MAC/IP info.
I don't even see anything about WDS mode in the Star OS using version 1.1.12 - 3299. Is this not under the config of the Infrastructure wireless card used in this hotspot?
Tim D
WDS options are under the Wireless card configuration dialog. It should be available in the later releases v1.12.x and newer.
ok, what if we pretend I am kinda slow and do not sleep much. I don't see anything labeled as WDS and I have version 1.12.5. Is it called something else for us slow people.
Maybe since I don't know what WDS is it really means something else?
Steve
09-30-2003, 03:50 PM
From the menu at the top....
Wireless
Wlan1
Config Current Card
From the dialog that just opened up...
WDS Setup (Big Green Button)
Enter the MAC address of the other AP you want to WDS with and check the Enable button.
Go to the other AP and do the same thing.
Accept Changes
File / Save Changes
File / Activate Changes
You need both AP's on the same channel. Search the Forum's (Button at the top of this web page with "Search" next to it) for more information on setting up IP's, routing, etc. for WDS.
do you have any general information on WDS? What is it, what does it do, how you set it up etc.
Tim D
Ok, from what I can figure out about WDS without documentation or sufficient documentation here is my problem.
My main 2.4 AP has 2 radios. Both are in AP mode. Both have to be in AP mode as they feed 2 sectors. When I try to setup WDS it tells me that I can't have the main router/AP in AP mode. The secondary towers get their feed from this main AP. Can I use WDS in this configuration and keep the main AP in AP mode? If not then WDS will not work.
Tim D
This should answer some questions regarding WDS, and how it functions.
http://www.proxim.com/support/techbulletins/TB-046.pdf
will the star os let me use the main AP to feed the 2nd level tower and still still use WDS?
oh and I still can't find a way to view the DHCP request MAC addresses on a Star-OS AP in routing mode.
Steve
09-30-2003, 07:00 PM
Setup your remote syslog and parse the log files for DHCP requests. I think you will see the requesting MAC there.
As of version 1.12.6 we provide a new DHCP server called DHCP auto-auth (available under the Interfaces menu). This DHCP server works as a substitute to the larger one, and also provides a DHCP lease view so you can see which users are using the IPs.
If you need features of the larger DHCP server for things such as static IPs, etc, then you can follow the method as shown by Steve to track your IP usage.
To use DHCP auto-auth as a standard DHCP server, simply make sure the 'Use Radius' checkbox is unchecked under the configuration dialog.
Thanks!
You mean to say that I have to setup a syslog server or whatever that is (never used one, never had one, don't know what one is) JUST to see the mac address of the computer or router making a DHCP request ??
Let's pretend I don't know how to run or where to run or what a syslog server is.
Then let's pretend that I don't want to run some type of dedicated service for such a small task.
Then le'ts pretend that all I want to know is the mac address making the dhcp request so I can bandwidth control my customers by ip address and I need to make sure their ip address is the same without trying to get the customers to keep up with a static ip address.
cisco this is done by simply entering = show ip dhcp binding
done, that's it. No brain surgery etc. While I realize this is not a cisco there has to be some method of getitng this information....HAS TO BE!
Now when I look at the ARP table I only see the mac address of the radio/bridge and not the computers behind it which are making the dhcp request ...thus I can't give them a static dhcp assignment and thus can not control their bandwidth.
Frustrated and confused without bandwidth Control !!!!
Tim D
Oh and I have the latest version and it's not 1.12.6 it's 1.12.5 in the CPE SBC version that I have JUST upgrade to. Also the lessor DHCP server wouldn't help if it doesn't do static DHCP assignments.
I don't mind paying for the server/router versions but not for customer cpe usage so we stopped using Star-OS for clients. I guess the CPE won't go to the latest versions anyway.
Tim D
Steve
09-30-2003, 09:37 PM
Just in the time you've spent on this thread alone you could have loaded Freebsd on a junk pc and had remote syslog running. Another 12 minutes searching Google and you could have found and implemented a script to parse your log files. I'm not sure how long you'll have to search to find a clue though. I'll apologize in advance for that one but I just couldn't help myself. Good Luck.
And I now have said Syslog running but I am being overwhelmed with messages from other places on the network.
I didn't want to have to run another application for reasons such as this. It will take some time to decipher this software and figure out what all the different messages mean and why it is getting about one message per second.
Tim D
lonnie
09-30-2003, 11:37 PM
I have read and re-read your posts and I am assuming you are bridging the AP but I cannot understand why you do not have an association screen that will show the IP and MAC that was last logged. You do not always use F1, as that is for the first radio card, and if that card is Infrastructure it will not have anything to show. For the second radio card hit F2, for the third F3, and so on. Each card in AP mode has an Association screen.
We have a bridged AP and it shows that screen quite nicely - that was our first task for the AP. We considered it essential to see all the units that are associated. Also in this case we do the DHCP at the unit that the bridge considers to be its gateway.
Do you have some sort of client bridge you are connecting? If so then this is the culprit that is hiding the MAC. That is what pseudo bridges do, and client mode can only be achieved by a pseudo bridge by doing proxy arp.
Send me a private email with the IP and password. I would not mind having a look at your setup to see if it can provide you with the info you need to do bandwidth control.
As for the CPE being a release behind, this is just the beginning. We have said the CPE is at the end of enhancement and will only get fixes from now on. We could not keep adding more and more code to an 8 MB image forever.
I would gladly share the ip address but the ones I am having trouble with are the APS that are routing and not bridging...per your suggestion :)
I can easily see all the mac addresses of the connected radios and have always been able to do so. HOWEVER since I have to do IP address bandwidth control and use DHCP to assign each customer computer it's own ip address, I need the mac address of their computer so I can do a hardware assignment in the DHCP config file. If they have 5 computers behind a bridge, obviously the status screen is only going to show the 1 Mac address for the Radio they are connected with and not any information on the 5 computers. I can see the multiple ip addresses flash on that screen (last ip used) but that still doens't give me the mac adress of the computer.
I can walk the customer through the process of giving me the mac address, that averages proably 30 minutes or more with most customers as they don't know &*()&
Tim D
oops, I meant to say that the APs are on Private IP addresses currently...however I am off network these days and need to give each AP a public address anyway.
Tim D
lonnie
10-01-2003, 08:37 AM
What you are asking for cannot happen. Any systems like the pseudo client bridges hide the client MAC from the upstream systems. That is how they accomplish bridging and nothing we can do on StarOS is going to recover a MAC that is simply not present.
I hate to say it but you have saved money on the cheaper client bridges but have lost control and are now forced to pay a higher support cost.
A discarded PC (166 MHz Pentium or better, 64 MB ram, dual Ethernet) and you have a router that can run our stuff at the client and give you all the new Hotspot and Radius control. Put this between the bridge and the clients and you get all the benefits since the router deals directly with the user.
Once you get to this level you have a central radius database that contains the client MAC (available from the router ARP) or user name and password and you can then assign IP and CBQ from the radius. He doesn't pay his bill you disable him in radius and he is shutdown. Change his speed and when he reauthenticates he picks up new settings. It simplifies things, but you need to have our software talking directly to the client.
The eeZee config makes it possible to handle misconfigured client systems and it works well with Hotspot and radius systems. The guy can have IP of 1.2.3.4, mask of 2.3.4.5, and gateway of 5.6.7.8 and he can still get out and you have his speed still set via radius (as long as he has valid username/password or MAC).
This is all new stuff. We would have liked to have had it last year, but it all takes time. Now that it is here we hope people can integrate it into their designs.
well the cisco can see the DHCP request MAC by simply typing
show ip dhcp binding
Taa daa
that's it. That's all I wanted the Star-OS to do was show me the dhcp address of the device making the request...and I know that all these bridges are passing it out somehow because the cisco sees it without issue....however the clients behind the Star-OS boxes use the star-OS DHCP instead.
And the bridge sees it or it would not show up in the syslog server which receives it's info from the Star-OS. Basically Its obvious the Star-OS has the information, I just want it to show it to me!
Tim D
On FreeBSD I can type tail /var/log/messages | grep "string" to view dhcp request. Can a similar option be included to show the dhcp binding in StarOS?
I am shocked that there isn't one or that they claim it isn't possible. How can a router that sends the information desired to a syslog server not actually have the information in the first place? I guess I am just stupid as I would think in order to give it, you must first have it.....if this were not the case, I would really enjoy writing checks!
Tim D
I should mention that even though this particular feature is lacking etc, I have had good luck with the software other then some update problems in the beginning. The documentation is very light also but it runs pretty solid.
Now the soekris boards on the other hand have lots of problems with long ethernet runs....short ethernet runs....or just ethernet in general. Anyone running the Soekris with Star-OS over 250 foot plus of cat-5 without problems? Currently we use the 48v 3com POE injector.
Tim D
Glad you are having success with the software. We have recently updated the CPE version to v1.13.2b4 (available in the BETA forums). This release includes all the accumulated fixes including some updates such as DHCP client, new DHCP server (dhcp auto-auth, which contains a DHCP lease view) and more.
The Ethernet problem with the Soekris systems seem to be hit and miss, as some experience problems, and others do not. Try our new release and see if it helps any.
Thanks!
thanks and I will give it a shot. I don't think the software has anything to do with the soekris problem, they just don't like ethernet much and cause us much grief at the top of our 160 foot water tower.
Glad to hear abou tthe DHCP server. The only negative thing I can think of with that is the fact you can't do hardware/mac assignment and thus can't use bandwidth control based on IP address. We run a seperate bandwidth control unit that does the entire network, some based on mac address control, other on ip address control.
Like to see adjustment ability to the burstable bandwidth control on the soekris also. burst to xx speed for xx seconds then drop xx every xx seconds until back to committed info rate...:)
Tim D
Yes, the new DHCP server is much simpler that the larger one that is already included, and does not provide static IP assignments. The larger one does allow for static assignments for your customers, with the exception of not being able to see your active leases which is not critical if you are doing nothing but static leases.
We do not have a burst rate, however we do have a fallback, which works similar to how you mentioned. If you specify 'fb' in front of the given bandwidth amounts, then that pipe will allow the user to have sustained throughput at that speed for 10 seconds, and then will drop 10% every second until it reaches 50% of it's original speed. Once the pipe's new capacity drops below 75% utilization, it will regain 10% every second until it reaches it's initial speed, or the user begins downloading again. The % figures are not configurable at the moment, however this is a planned enhancement.
Thanks!