Prev: Finder disappears...
Next: help: cloning Windows partition - "not enough space"
From: Amanda Ripanykhazov on 26 Oct 2009 08:23
Got a problem which has stumped Apple so naturally I turned here.

My computer wont pick up an IP. It keeps picking up a spoofed one
(what Apple calls a self-assigned one)

Was in the Apple store and this problem flummoxed the Genuis Bar guy.
he kept trying to connect and it didnt work. After trying restarting,
changing networks, changing from DHCP to Manual Assign etc etc etc,
about a dozen tries later, he got the mysterious error message
Do you want the application "configd" to accept incoming network
connections
and
Do you want the application "mdnsresponder" to accept incoming network
connections (both of which he allowed, although he had never seen
those either and said they must be some kind of firewall) and suddenly
it connected

It stayed working for a few days, connecting as and when necessary to
the four networks available where I am before peremptorily stopping
completely again for no apparent reason on around Saturday.

This time Apple Tech Support sent it to their internet and multimedia
team where they told me to remove airport.plist,
network.id.plist,networkinterface.plist and preferences.plist and
reboot to recreate them. It connected properly again (I think it
asked the two mystery 'Allow/Deny Questions' again) and this time
lasted only a day.

So I tried deleting these files myself and restarting. Curiously the
files hadnt been recreated in toto. I found preferences.plist
and ,networkinterface.plist, but airport.plist, is now called
com.apple.airport.preferences.plist but network.id.plist doesnt seem
to be there at all? (there IS a file called com.apple.nat.plist?) In
any event I deleted the three files again and restarted but this time
it didnt help with the problem at all.

So another call to Tech Support got me to the apparently highest level
tech support when the Internet and Multimedia team were baffled. They
couldnt figure out how to cure it so they had me boot off an install
disc and tried connecting. Hey Presto, it connected fine, indicating
that as we knew from the visit ot the Apple store (for overheating)
that there wasnt anything wrong with the hardware. So they concluded
that only a full archive and reinstall was likely to help.

When I hear this, I naturally think that they cant identify the
problem (this is what PC tech support tells you when they want to get
you out of their hair for a month or so in the HOPE that it will get
rid of the problem) so I was wondering whether anyone else could? To
me it sounds suspiciously like 'The Problem No One Wants To Agree Is
There', that the NIC card is somehow losing sensitivity (not
interference, but LOSING sensitivity). When this problem first
started, I tried moving close to the WiFi source and found that it
didnt make any difference to whether the system picked up a Spoofed IP
but at the end of this process I am not so sure.

There IS an addendum here: This morning, I found I COULD connect after
only doing the configd of the deny/alllows (but curiously slowly). I
dont believe this will either last or be reliable so I am posting
here. Has anyone established yet that this business of asking whether
I want the applications "configd" and "mdnsresponder" to accept
incoming network connections an unknown by-product of some OSX update
and has a cure been put out by Apple yet?

From: Geoffrey S. Mendelson on 26 Oct 2009 09:34
Amanda Ripanykhazov wrote:
> Got a problem which has stumped Apple so naturally I turned here.
>
> My computer wont pick up an IP. It keeps picking up a spoofed one
> (what Apple calls a self-assigned one)

It's not a spoofed IP, it's a self assigned one. When you use DHCP to assign
an IP address, it starts out with the self assigned one. That's because
more likely defaults of 0.0.0.0 or 255.255.255.255 mean something special
and everything else could be in use, e.g. 1.2.3.4, etc.

That's just an IP address that was picked to indicate that DHCP was chosen,
but an IP address had not successfully been negoitated.

It would help if you told us what you were using. Model of the Mac, type
of airport card, what you were trying to connect to, operating system
version, etc.

Do you have a third party firewall, such as "Little Snitch" installed?

>
> There IS an addendum here: This morning, I found I COULD connect after
> only doing the configd of the deny/alllows (but curiously slowly). I
> dont believe this will either last or be reliable so I am posting
> here. Has anyone established yet that this business of asking whether
> I want the applications "configd" and "mdnsresponder" to accept
> incoming network connections an unknown by-product of some OSX update
> and has a cure been put out by Apple yet?

The process of connecting to a WiFi network is rather complicated, and
lots of things have to work properly. Along the way all sorts of problems
can occur and things can intefere with the connection. Microwave ovens,
older cordless phones, radar systems, and even bluetooth can interfere.

I have an older Mac with an external bluetooth dongle (little thing that
plugs into the USB port). It interferes with my wifi. I have to move it away
from the Mac to get the wifi to work.

I also have the problem with some brands of USB memory sticks. :-(

The first thing I would do is to download a wifi sniffer, such as kismac
and see what it says. The signals might not be strong enough, or there are
other strong signals nearby, overloading your computer.

The second is the difference between an open network, one that requires
authorization and encryption.

An open network can be joined by anyone.

An athorized network requires a password or another credential to join.

An encrypted network uses data encryption to prevent computers without the
encryption key to understand the data and communicate.

When you connect to a Wifi network, your computer will try to join it.
If it does not use authorization, it will join it immediately. If it uses
authorization, a user name and password, or an authorization key has to be
sent and approved.

Once you join a network, since you are using DHCP, the "self assigned
IP address" is assigned to your Wifi connection and the dhcp client software
tries to negotiate an IP address.

Now here's the rub,as it were. If your network is encrypted but does not
use authorization and you have the wrong key (WEP) or don't properly
negotiate one (WPA), your computer will never actually get an IP
address, although it will look like it has connected for a while,
because it has joined the network.

After DHCP fails, it will go back to being not joined to any network, but
the self assigned DHCP address will remain.

configd is the part of MacOS that acts as a dhcp client. It is what negotiates
an IP address from a DHCP server (among other things).

mdnsresponder is the program that looks up internet names from a domain name
server (DNS). For example, if you enter www.apple.com, your computer can not
reach it over the internet. It has to convert that name (in the form of
host.domain.domain) to an IP address, and this is what does it.

The IP address of an appropriate DNS server (it would not make sense to
tell you it's name) is usually sent in the information provided by DHCP.

My GUESS is that since it works when booted from a DVD and you get the
stange messages, is that there is some sort of firewall problem, most likely
caused by a third party firewall.

Maybe you can tell us more about the message, I've never seen it myself.

Geoff.

--
Geoffrey S. Mendelson, Jerusalem, Israel gsm(a)mendelson.com N3OWJ/4X1GM
From: J.J. O'Shea on 26 Oct 2009 09:34
On Mon, 26 Oct 2009 08:23:40 -0400, Amanda Ripanykhazov wrote
(in article
<f4bfa8f8-4dee-471c-b861-32f0ec61c907(a)x15g2000vbr.googlegroups.com>):

> Got a problem which has stumped Apple so naturally I turned here.
>
> My computer wont pick up an IP. It keeps picking up a spoofed one
> (what Apple calls a self-assigned one)

If the IP begins with the sequence 169.254, that's an APIPA address, an
Automatic Private IP Address. This is a standard, invented by Microsoft.
(Hey, they occasionally have good ideas. Not often, but when they do it
should be pointed out that they did something good for a change.) If you are
getting an APIPA address, that means that your system is set for DHCP but is
not seeing the DHCP server for one reason or another.

>
> Was in the Apple store and this problem flummoxed the Genuis Bar guy.
> he kept trying to connect and it didnt work. After trying restarting,
> changing networks, changing from DHCP to Manual Assign etc etc etc,

If he changed from DHCP to a manual, fixed, IP and you still didn't get
connected then the problem is that your machine is not seeing the network,
period. That could be either hardware (bad cable, bad Ethernet port on the
Mac, bad Ethernet port on whatever you're connecting to, wireless connection
problems, dead network, other possible problems) or software (incorrectly set
up firewall, MAC address filtering, bad wireless security key, system problem
on the router, other possible problems)

> about a dozen tries later, he got the mysterious error message
> Do you want the application "configd" to accept incoming network

If configd isn't operational you're never going to get a network connection
on a Mac. Period. See
<http://www.afp548.com/article.php?story=20041015131913324>. If you have your
firewall incorrectly set configd will not run. The simple solution to most
configd problems is to turn off the firewall. Once you have a good
connection, you can then configure your firewall correctly.

> connections
> and
> Do you want the application "mdnsresponder" to accept incoming network

mdnsresponder is a zero conf service. It's used, among other things for DHCP.
See <http://developer.apple.com/networking/bonjour/faq.html>. Again, if your
firewall is set incorrectly, Bonjour (and therefore mdnsresponder) will not
work. It would appear that your problem is related to a misconfigured
firewall. At least that's the first place I'd look.

> connections (both of which he allowed, although he had never seen
> those either and said they must be some kind of firewall) and suddenly
> it connected

He's never heard of configd or Bonjour? I doubt this.

>
> It stayed working for a few days, connecting as and when necessary to
> the four networks available where I am before peremptorily stopping
> completely again for no apparent reason on around Saturday.

Sounds like a firewall problem again.

>
> This time Apple Tech Support sent it to their internet and multimedia
> team where they told me to remove airport.plist,
> network.id.plist,networkinterface.plist and preferences.plist and
> reboot to recreate them. It connected properly again (I think it
> asked the two mystery 'Allow/Deny Questions' again) and this time
> lasted only a day.

Your firewall settings are being corrupted somehow. They asked you to delete
the network communications pref files. When you did that, everything worked.
It's supposed to stay working, so long as you don't change anything in the
firewall. Have you gone to System Preferences/Security/Firewall and turned it
off?

>
> So I tried deleting these files myself and restarting. Curiously the
> files hadnt been recreated in toto. I found preferences.plist
> and ,networkinterface.plist, but airport.plist, is now called
> com.apple.airport.preferences.plist but network.id.plist doesnt seem
> to be there at all? (there IS a file called com.apple.nat.plist?)

not on the system I'm on.

> In
> any event I deleted the three files again and restarted but this time
> it didnt help with the problem at all.
>
> So another call to Tech Support got me to the apparently highest level
> tech support when the Internet and Multimedia team were baffled. They
> couldnt figure out how to cure it so they had me boot off an install
> disc and tried connecting. Hey Presto, it connected fine, indicating
> that as we knew from the visit ot the Apple store (for overheating)
> that there wasnt anything wrong with the hardware. So they concluded
> that only a full archive and reinstall was likely to help.
>
> When I hear this, I naturally think that they cant identify the
> problem (this is what PC tech support tells you when they want to get
> you out of their hair for a month or so in the HOPE that it will get
> rid of the problem) so I was wondering whether anyone else could? To
> me it sounds suspiciously like 'The Problem No One Wants To Agree Is
> There', that the NIC card is somehow losing sensitivity (not
> interference, but LOSING sensitivity). When this problem first
> started, I tried moving close to the WiFi source and found that it
> didnt make any difference to whether the system picked up a Spoofed IP
> but at the end of this process I am not so sure.

looks like a firewall problem.

>
> There IS an addendum here: This morning, I found I COULD connect after
> only doing the configd of the deny/alllows (but curiously slowly). I
> dont believe this will either last or be reliable so I am posting
> here. Has anyone established yet that this business of asking whether
> I want the applications "configd" and "mdnsresponder" to accept
> incoming network connections an unknown by-product of some OSX update
> and has a cure been put out by Apple yet?
>



--
email to oshea dot j dot j at gmail dot com.

From: Amanda Ripanykhazov on 26 Oct 2009 13:31
On Oct 26, 9:34 am, J.J. O'Shea <try.not...(a)but.see.sig> wrote:
> On Mon, 26 Oct 2009 08:23:40 -0400, Amanda Ripanykhazov wrote
> (in article
> <f4bfa8f8-4dee-471c-b861-32f0ec61c...(a)x15g2000vbr.googlegroups.com>):
>
> > Got a problem which has stumped Apple so naturally I turned here.
>
> > My computer wont pick up an IP. It keeps picking up a spoofed one
> > (what Apple calls a self-assigned one)
>
> If the IP begins with the sequence 169.254, that's an APIPA address, an
> Automatic Private IP Address. This is a standard, invented by Microsoft.
> (Hey, they occasionally have good ideas. Not often, but when they do it
> should be pointed out that they did something good for a change.) If you are
> getting an APIPA address, that means that your system is set for DHCP but is
> not seeing the DHCP server for one reason or another.
>
>
>
> > Was in the Apple store and this problem flummoxed the Genuis Bar guy.
> > he kept trying to connect and it didnt work.  After trying restarting,
> > changing networks, changing from DHCP to Manual Assign etc etc etc,
>
> If he changed from DHCP to a manual, fixed, IP and you still didn't get
> connected then the problem is that your machine is not seeing the network,
> period. That could be either hardware (bad cable, bad Ethernet port on the
> Mac, bad Ethernet port on whatever you're connecting to,  wireless connection
> problems, dead network, other possible problems) or software (incorrectly set
> up firewall, MAC address filtering, bad wireless security key, system problem
> on the router, other possible problems)
>
> > about a dozen tries later, he got the mysterious error message
> > Do you want the application "configd" to accept incoming network
>
> If configd isn't operational you're never going to get a network connection
> on a Mac. Period. See
> <http://www.afp548.com/article.php?story=20041015131913324>. If you have your
> firewall incorrectly set configd will not run. The simple solution to most
> configd problems is to turn off the firewall. Once you have a good
> connection, you can then configure your firewall correctly.
>
> > connections
> > and
> > Do you want the application "mdnsresponder" to accept incoming network
>
> mdnsresponder is a zero conf service. It's used, among other things for DHCP.
> See <http://developer.apple.com/networking/bonjour/faq.html>. Again, if your
> firewall is set incorrectly, Bonjour (and therefore mdnsresponder) will not
> work. It would appear that your problem is related to a misconfigured
> firewall. At least that's the first place I'd look.
>
> > connections (both of which he allowed, although he had never seen
> > those either and said they must be some kind of firewall) and suddenly
> > it connected
>
> He's never heard of configd or Bonjour? I doubt this.
>
>
>
> > It stayed working for a few days, connecting as and when necessary to
> > the four networks available where I am before peremptorily stopping
> > completely again for no apparent reason on around Saturday.
>
> Sounds like a firewall problem again.
>
>
>
> > This time Apple Tech Support sent it to their internet and multimedia
> > team where they told me to remove airport.plist,
> > network.id.plist,networkinterface.plist and preferences.plist and
> > reboot to recreate them.  It connected properly again (I think it
> > asked the two mystery 'Allow/Deny Questions' again) and this time
> > lasted only a day.
>
> Your firewall settings are being corrupted somehow. They asked you to delete
> the network communications pref files. When you did that, everything worked.
> It's supposed to stay working, so long as you don't change anything in the
> firewall. Have you gone to System Preferences/Security/Firewall and turned it
> off?
>
>
>
> > So I tried deleting these files myself and restarting.  Curiously the
> > files hadnt been recreated in toto. I found preferences.plist
> > and ,networkinterface.plist, but airport.plist, is now called
> > com.apple.airport.preferences.plist but network.id.plist doesnt seem
> > to be there at all? (there IS a file called com.apple.nat.plist?)
>
> not on the system I'm on.
>
>
>
>
>
> > In
> > any event I deleted the three files again and restarted but this time
> > it didnt help with the problem at all.
>
> > So another call to Tech Support got me to the apparently highest level
> > tech support when the Internet and Multimedia team were baffled.  They
> > couldnt figure out how to cure it so they had me boot off an install
> > disc and tried connecting. Hey Presto, it connected fine, indicating
> > that as we knew from the visit ot the Apple store (for overheating)
> > that there wasnt anything wrong with the hardware. So they concluded
> > that only a full archive and reinstall was likely to help.
>
> > When I hear this, I naturally think that they cant identify the
> > problem (this is what PC tech support tells you when they want to get
> > you out of their hair for a month or so in the HOPE that it will get
> > rid of the problem) so I was wondering whether anyone else could?  To
> > me it sounds suspiciously like 'The Problem No One Wants To Agree Is
> > There', that the NIC card is somehow losing sensitivity (not
> > interference, but LOSING sensitivity).  When this problem first
> > started, I tried moving close to the WiFi source and found that it
> > didnt make any difference to whether the system picked up a Spoofed IP
> > but at the end of this process I am not so sure.
>
> looks like a firewall problem.
>
>
>
> > There IS an addendum here: This morning, I found I COULD connect after
> > only doing the configd of the deny/alllows (but curiously slowly). I
> > dont believe this will either last or be reliable so I am posting
> > here.  Has anyone established yet that this business of asking whether
> > I want the applications "configd" and "mdnsresponder" to accept
> > incoming network connections an unknown by-product of some OSX update
> > and has a cure been put out by Apple yet?
>
> --
> email to oshea dot j dot j at gmail dot com.

Thanks for your amazing help guys: What I have done is to go into
firewall and specifically allow configD. This seems to have minimised
the temporary problem with that error message. But I dont think that
the whole problem can be laid on the firewall (though I WILL try your
suggestion of disabling the whole firewall for a while and seeing what
happens)

More importantly I suspect some loss of sensitivity at the AirPort
card end along with the possibility which I DO accept that there are
other strong signals nearby, overloading my computer. If I move my
computer across a certain room between the place where I have these
problems and the router, I can almost tangibly see the signal drop off
at around 25 feet from the router and with nothing significant
intervening at that point: There are no electrical appliances of ANY
type nearby! So much so that I have installed and configured another
router (a Buffalo 80211G) as a DD-WRT_VAP repeater to amplify this
signal! And cranked the output power up to a legal maximum of 99
milliwatts. I was toying with the idea of doing this with a WRT-150N
which I have lying around as it probably has better range but I havent
been able to figure out whether this particular router (a VT1) can be
set up as a repeater and the DD-WRT forums are a bit quiet on this
point?

The card is an AIrPort Extreme with Broadcom firmware version BCM43xx
(4.170.25.8) and I wouldn't have any idea how to update the firmware
otherwise than through an Apple Update. Is there some way of doing
this? Anyway let me try Kismac and see what happens.(I didnt know
that there was a Mac version of Netstumbler). Computers right next to
this one can connect properly and this one cannot see enough of a
signal to assign a DNS. I had been told by Fios that only a full
digital spectrum analyser can tell me exactly what interference there
is which might be preventing my computer from accessing my network in
circumstacnes where occasionally it WILL access a neighbour's one
instead! I doubt that it is an incorrectly set password on the WEP
end or this computer wouldnt ever be able to access my network through
my FIOS router. However I have a linksys VoIP router with no
encryption on the same network and it has all the same problems as the
FIOS one does. I am pretty sure I have NO third party firewall.
From: Fred Moore on 26 Oct 2009 13:42
In article
<f4bfa8f8-4dee-471c-b861-32f0ec61c907(a)x15g2000vbr.googlegroups.com>,
Amanda Ripanykhazov <dmanzaluni(a)googlemail.com> wrote:

> Got a problem which has stumped Apple so naturally I turned here.
>
> My computer wont pick up an IP. It keeps picking up a spoofed one
> (what Apple calls a self-assigned one)
> [tale of aggravation and woe omitted ;) ]

This is a long shot, but I've seen it work on occassion.

Go to the Network prefs pane. Select Using BootP from the Configure:
popup. Click Apply and see if you can connect. If you do, you can change
the Configure selection back to DHCP or whatever. Don't ask me why this
works, but it might. BootP forces the issue somehow.
 |  Next  |  Last
Pages: 1 2 3
Prev: Finder disappears...
Next: help: cloning Windows partition - "not enough space"