Airport Stops working (Sort of)
 

For our home network we used a single airport base station to acting as a router. This did not give us the range we needed so we bought recently an airport extreme base station which acts as a router and out the old base station in a different location (no longer distributing ips). Several times each day we loose our internet connection. Using the Airport Admin Utility I can see the base stations. i can also access our printers webpage. However, our connection to the outside world stops working. This can be remedied by restarting the base station that is acting as a router, either by unplugging it or using the utility. While this solves the problem this is not somethign i want to continue doing. below im listing some information that may or may not be relevant.

Airport Extreme (router)
Configured using DHCP- it has an ip and router address from rcn. it is also set to subnet mask 255.255.255.0
it is configured to distribute ips
to share a single ip using DHCP and NAT
Iv tried several values for the DHCP Lease including 4hrs an 9999 days. neither of which made any difference.

Out other base station an old airport:
also configured using DHCP
it has an IP of 10.0.1.2 by the the router (10.0.1.1) and a subnet mask of 255.255.255.0
it is not configured to distribute ip addresses

Even though this is the case i have gotten error messages on different computers on the network saying "IP Configuration
10.0.1.4 is in us by 0:a:27:d8:fa:98, DHCP Server 10.1.1.1"

any ideas on how to fix this
thanks
-cholst

This is a shot in the dark, but sounds like a problem i was having.

Do you happen to have any cordless phones in your house that are in range of the wireless base station?? If you do, and they operate on a 2.4 GHz wireless frequency like the airport wireless routers (or you have any other appliance that may operate on a 2.4 GHz frequency like a microwave or something), you will lose your connection to the base station whenever the phone rings (or whichever appliance in question is 'activated')

I had this problem and was forced to pick up a 900 MHz cordless phone and can the 2.4 GHz one.

If it isn't an interference problem, then i don't know what to tell you except make sure you have the latest firmware installed for both your base stations.

mike

so i have no cordless phone or any other devices that could interfere with the network, and my basestations are at channels 1 and 10. i also think its probably some kind of software setting based on the problem, becuase once i restart the base station everything works fine
-cholst

Could be a neighbors Cordless etc causing interfearence
 

Could be a neighbors Cordless etc causing interfearence...

You can try turning DHCP off and manually setting all comp and BaseStation IP's. If you have not checked it out you may like to read Apple's pdf on designing Airport networks to check your network can not be improved.

If you have tried everything you can think of and still no joy then I would hard reset both BaseStations. Sadly too often this has been the only thing that will fix irrational behaviour in my experience. See Apple's Airport support section for more info as the procedure varies between models. dD

OK Yeah trouble shooting...
 

Well Do not worry about the web worry about connectivty to the Airport/Base Station

Trying using the terminal app in Util folder to ping -s the base stations IP e.g. 192.168.1.1 or what ever you set it for.

If there is any packet loss you indeed might be getting interference.

You can also ping -s 1500 instead of the default packet size...

-------------------------------------------------------------------

Also keep in mind it could be the Cable/company signal and subsqunelty the cable modem causing you grief. I have to reset my Cable modem and then my router anywhere from daily to weekly.

The DHCP lease you mention here is the lease for the IP address that the basestation gives to your Macs. It doesn't seem likely that this is the problem. Instead it seems more likely that the problem is with the DHCP lease that the base station itself gets from your ISP.

You should check to see if that Ethernet address (0:a:27:d8:fa:98) belongs to one of your Macs. It could be the "Ethernet address" of an Ethernet card or it could be the "Airport Id" of an Airport card. You can see these addresses in the Network preferences pane. If you find that it belongs to one of your machines, that should narrow down the problem.

And which machine does the IP address 10.1.1.1 belong to?

first of sorry i mistyped when i said 10.1.1.1 i meant 10.0.1.1 which is the router(Base station extreme) ill go check the ethernet ids
thanks
-cholst

Whoops
 

Did not even see the Address in use part of the message....

I do not think Hocky did either... Sorry about that..

Different Flavor of problem...

************* You and Hayne seem to have a bead on it....

Keep us informed...

A thanks you to Hayne. THe problem does appear to be with the DHCP lease given by the cable company, and the only fix seems to be more money, so ill just have to live with it. Thanks to all for helping me
-Cholst

Weird
 

The whole point of using A router, wireless or otherwise is for the Cable Modem or DSL Modem to give its Single DHCP lease to the wired/wireless router. In your case the Airport base stations (which can support many clients).

And then The wired/wireless router Provides DHCP services to the computers on the lan or wireless pointed towards it.

I do remember in your post that you were using a spiffy and Unique feature of Daisy Chaining two wireless routers or Airports togehter to increase range (other options include additional attennas etc.).

In Short there is no reason to pay your ISP/Cable Company Extra.

i agree and have no intention of paying my isp extra. also my base stations arent daisy chained, both are plugged into a wired ethernet network. the problem with the cable company is that they want you to rent a special router from them that avoids these problems, but ill just get around them. thanks again
-Cholst

You sound like you have solved your problems some other way so maybe it doesn't matter.
But I'd just like to reiterate what anthlover has said - the way to go is to have one and only only one thing connected to your cable modem: a router.
Everything else on your network should be hooked up to that router. Then your ISP sees only the one IP - that of the router. And you manage your own internal network the way you want.

my setup is already exactly the way you described it. my problems arises from the fact that my isp changes the ip that the router gets very often, thus forcing me to restart my router
-cholst

Something is wrong here. Why should your ISP changing the IP address that it assigns to your router cause you any problems? You shouldn't care what IP address your router has. It is only people outside your network who care about your router's IP address.

the reason that i care is that my router stops acting as a router when the ip gets changed. whenever this happens my lan works fine but i cannot access anything outside of it without restarting the base station
-cholst

Okay, so your "router" is your Airport Extreme basestation. And the ABS is the only thing that is connected to the cable modem - is that correct?
I'm assuming that the cable modem is connected to the WAN port of the ABS and you have other machines connected via the LAN port of the ABS.

When you have the trouble, what is the external IP address of the ABS? (i.e. the address assigned by your ISP) Does it change when you have the trouble?

What did you find out when you looked for the hardware (Ethernet or Airport) address that was reported as already using that IP in the error message? You shouldn't negelect this - it is an important clue.

You should also read this thread:
http://forums.macosxhints.com/showth...=&postid=77823
concerning a similar problem. That person found that the problem was solved only by replacing the ABS - i.e. it seemed to be a hardware problem.

Lets simplify for trouble shooting
 

Stop me if I reiterate somthing untrue

1) You have two Airport basestations. An Orginal and an Extrteme.
2) You are using the former to create/enlarge your wireless range of your wireless network.
3) You wired/wireless clinets have no trouble with Lan/wireless access but all your computers loose access to the "Internet" with some frequency, until you reset the Cable modem and or Routers (Airport) or both.

4) You have discounted the possabilty that:
The Cable/company ISP signal and subsqunelty the cable modem is causing you grief. I have to reset my own Cable modem and then my router anywhere from daily to weekly (usually every few days).

5) You discount #4 because you are getting a message about a MAC address already using an IP. e.g. "i have gotten error messages on different computers on the network saying "IP Configuration 10.0.1.4 is in us by 0:a:27:d8:fa:98, DHCP Server 10.1.1.1"

Now I am assuming "10.1.1.1" is Your Airport Extreme router Handing out DHCP leases. And 0:a:27:d8:fa:98 is the MAC Address of one of your systems wireless or wireed Ethernet interfaces. ** This error message seems indictive of two machines fighing over Address 10.1.1.4 aka Address #4 in your Lan Topology.

On the matter of DHCP Lease Length and having tried "4hrs an 9999 days" Those are book end times. Too short and too long. I would try 24 hours/1day and perhaps progress to somthing like two days etc.

*** Before we go further there are two basic possabilties here: ******

***1) ISP Capble compnay singnal goes Bonkers and you have to reset to regain your connection periord (it happens you yell at them they may come and fix if it happens to often).

***2) There are issues in your Router and Lan/wirelss

It is possible that some someone is stealing your access. e.g. Grabbing Address #4 or another one while one of your machines is asleep. Or could even be one of your own systems.

You can do a number of things to to help (some of them permenet some for testing):

1) Limit the number of Clients to exactly the number of systems you have
2) Turn of SYSID broadcasts so you are not Advertizing your wireless network (change the name of your wireless network to Cholst or what ever you like)
3) Turn off all Energy Saver settings but Monitor sleep
4) Change the password of your router from the default
5) Turn on Wep when your are ready (last step after everything elese, would probably not do wep until you have a better bead on the problem).
6) You may need to eliminate the older Airport station as a varible in the equation for a period of time.
7) There are options on most wireless routers to limit access to the network based on known MAC addresses e.g. "Just your computers" this can eliminate all guests

**** 8) Last but Not least Hayne Suggests in his Link, and it quite possible that your Airport Extreme router is faulty. That is ceratinly a possabilty. And one that requires you use A new Extreme for testing, or for a limited time the Older Airport station. Indeed as I mentioned in number 6 you might want to use one wireless AP or Router for a limited period of time to reduce the varibles in the Equation.

Could you sketch your set up? eg:

Your AXBS is quite capable of handling Dynamic IP's, the fault is either with your layout, Cable service, AXBS needs resetting (properly, not just power cycling) or a faulty AXBS. dD

my network looks much the way your example looked

cable modem
|
Airport Extreme Base Station (also acting as a router)
|
LAN( has 3 computers that are wired)
|
an Old Airport base Station (both of which airports are configured to allow roming0

There is an additional laptop that uses wifi but connects to which ever basestation has a strogner signal


Incase my diagram does not make much sense,
I have a Cable modem connected to the WAn port on my AXBS the LAN port is connected to a 8 port Ethernet switch, the switch is connected to an iMac and old PC and a network printer. there is also a cable that is uplinked to another switch that is connected to another PC and an airport base station. again there is also 1 tibook that uses wifi to connect but chooses which base station based on which has the stronger signal.

thanks
-Cholst

I'm leaning towards the AXBS being faulty seeing as by now you have defiantly tried the reset procedure i linked to earlier?

Disconnect the LAN from the AXBS, turn off the other ABS, connect to the AXBS with your wireless laptop and check for the internet connection dropping.

If it still drops and you *really* have tried resetting the AXBS

repeat with the old ABS instead, check for the internet connection dropping with your laptop.

CM
|
ABS ) ) ) Laptop

If both BS drop the connection then connect a mac directly to the CM & test again. dD

The simplifications in your network suggested by darndog for diagnostic purposes seem like a good approach.

And did you track down what machine had the hardware address (0:a:27:d8:fa:98) that was mentioned in the error message?
Are you still getting this type of error message?

Agreed:)
 

RE: Agreed:)

Send me to the Editor:)

Do Re-Read my post though if it the problem is not hardware related you will need to look at the other isuses....

Problem isolated
 

So im stupid is what it boils down to. On apple's website they specifically say that you cannot have airport configured for both roaming and NAT, and low and behold that is the configuration i have. The only way i can think of fixing this is to put each hub on a different network, but im afriad that this would cause problems if i ever tried to do anything across the network. any other ideas
cholst
ps sry for wasting any of your time

Glad it was not Hardware.
 

RE: Glad it was not Hardware.

Please read over Security suggestions in this thread.

Also Perhaps you can go with Just the Extreme Station and Bigger Attennas they Start at $30 bucks.....

Please note if you can Go All Exterme you also Get better Range. Or more Specfically better Real world Range/Speed. Means buying Extreme PC Card for machines that have 802.11b....

802.11b Gives Only 5mbs per sec Max and Drops down to 1mbs per sec quickly and even then sometimes it seems like .1 or .01 at the Edge of its range.

802.11g Gives About 25mbs per sec and rarely drops below 5mps per second.

Please note in a Mixed wireless network Extreme goes into Limp Mode and Essentailly becomes another 802.11b Base. While firmware updates have attempted to help fix. It really is not possible until wireless is a switched topology instead of hubbed/shared bandwidth Topology.

Look at the picture on page 41 and then read the section on Roaming and WDS Airport setup which starts on page 40 of this Apple pdf on Airport Network setup.

If the above link does not work you could try the one I posted earlier. :rolleyes: dD

It would make things very simple for you if you bought a router/switch box (very cheap nowadays) and let that router be your gateway to the cable modem. You could make that router be your DHCP server and then plug your Airport base stations into that router/switch and configure your Airport base stations to be in "bridge" mode - i.e. turn off NAT and DHCP on the ABS's. Then all your computers would get their Ip addresses from the new router box and all would be on the same subnet,

RE: Goood/Nice Idea, though I stand by Other issues:
 

RE: Goood/Nice Idea, though I stand by Other issues: Security, Pure 802.11g (speed and range), and Attenna signal boosting points raised at various points in the Thread.....

One ?

Is It inadverant that you suggest the person plug into (wired connection) both Airports into inexpensive 4 port $30 to $60 router/switch e.g. Linksys 4 port, etc.?
"and then plug your Airport base stations into that router/switch and configure your Airport base stations to be in "bridge" mode - i.e. turn off NAT and DHCP on the ABS's. Then all your computers would get their Ip addresses from the new router box and all would be on the same subnet.."

I would of thought You meant Plug one ABS into Hardware router (as the point of using two ABS's) was one of the ways to create a larger wireless network....

But Do Point All Computers and ABS's to Wired Router for DHCP/routing and do have ABS's in Bridge mode as suggested.

Good Luck.

Hayne, An extra router/switch is unnecessary, Cholst is wrong in thinking his network will not support NAT and Roaming. all he has to do is set up 1 Basestation as DHCP server & 1 as Bridge mode. This is fully explained in the .pdf I linked to in my last post and the 4th post of this thread. dD

Okay - that's good to hear. It seemed strange that there was a problem with doing it that way - and I confess I didn't read the PDF your referred to. Thanks.

Well iv read the pdf. I do have one set up as a dhcp server and the other as a bridge. I think the problem must then be in the aXbs b/c when i use the old base station as a dhcp server i encounter no problems, I have not however plugged in the new Base station as a bridge but so if there is no problem with using nat and roaming, and its not some other setting then i may be forced to switch the BSs which is not preferable becuase the old one doesnt have an antenna port
-cholst
ps
ive tried reseting it, but i still have problems

If you can get a basic setup working like so:then you could add the old Basestation as part of a WDS network:However I would suggest setting IP addresses manually throughout a Roaming layout will give more predictable results. (don't forget to add DNS servers on all the Mac's) I realise that this is pretty much your old setup, but there is nothing wrong with it, the only thing I can think of that will be screwing it is either the old BS is still distributing DCHP, the new AXBS is faulty or you have missed some setting somewhere, removing DHCP altogether and using Fixed IP's (all in the same subnet) should further clarify the situation. dD

Edit/ insure 'internet sharing' is disabled on all Mac's.