The macosxhints Forums - Wife is upset about our LAN/her Mac Performance

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Wife is upset about our LAN/her Mac Performance

My wife has a year-old MBP running 10.5.6. It is randomly disconnecting from the internet.

The network consists of an Actiontec DSL modem, connected to a MaxPower N wifi router. There is a G4 with a N network card, my MBP (not N), my PC with a G network card, a Wii, and my wife's MBP which has an N airport.

None of the other computers perform unexpectedly except from my wifes MBP.

I've tried:
Setting up a new network location
Setting a static ip address
Setting up a new user account
Moving the computer nearer the wifi router.

This strange behavior did not change after trying these changes.

I'm not sure of what to do next. I did notice that about half of the time, there is a log entry that the Airport went down, and then goes back up.

There are times when I can access the internet from her computer, and ping all of the computers on the lan, but when I try to ping her computer from my MBP or the PC or the G4, there is no response. I have Remote Desktop on my computer, and I can sometimes connect to her MBP, but I can never connect through Screen Sharing.

She is in the middle of school right now, so I don't want to do anything too drastic at this moment.

Has anyone seen any similar behavior, or have any insights?

Thanks,
Brett

Have you run the latest updates.
Or tried to change the wifi channel.

yes on both accounts.

Thanks,
Brett

Even thou you have a N network, I would set the router to G network and see if the connections is better.
you have a G connection coming from your PC and the wii. the network will only work as fast as your slowest connection.

i had something similar on a MB.. turned out the be something corrupt in the user account, setup a new user and it was fine... so transferred all the info over.. sorted

Yeah - I've tried both of those things, too. No, go.

Thanks,
Brett

Quote:

I'm not sure of what to do next. I did notice that about half of the time, there is a log entry that the Airport went down, and then goes back up.

Could we see the exact log entries to this effect, and a few before and after them too?

Trevor

It would also be useful to run the 3rd-party utility "iStumbler" (www.istumbler.net) on your wife's Mac to see what the noise level of your network is and whether other wireless networks are in the vicinity.

I'll get the log entries later tonight.

I ran iStumbler on my machine, but not hers - I'll do that again tonight. I did run APgrapher on her machine, and the noise looked low, but I don't remember the number.

I am much better versed on Xserves, do MBP come with hardware test DVD's? Do they have tests for airport cards?

Thanks,
Brett

Yes, there should be a way to boot to the Apple Hardware Test explained on the face of the DVD that came with the MacBook Pro.

I'm not sure whether the AHT tests include one for the built-in Airport "card" chipset, but I would guess that they do.

Trevor

Quote:

Originally Posted by brettgrant99 (Post 525424)

I ran iStumbler on my machine, but not hers - I'll do that again tonight. I did run APgrapher on her machine, and the noise looked low, but I don't remember the number.

And look to see if iStumbler's graph indicates the signal strength decreasing around the time of the problems.

Here is the log file where it says that the Airport went down and then up. When I went out to the computer it was not on the network, but there were no entries for a some time (maybe 3 hours) in:

All Messages
Console Log
system.log

The system log rolled over last night, so this part of the log is from yesterday

Code:

Mar 22 16:24:39 Pasha kernel[0]: sleep

Mar 22 16:24:39 Pasha kernel[0]: Wake reason = EC LID0

Mar 22 16:24:39 Pasha kernel[0]: System Wake

Mar 22 16:24:39 Pasha kernel[0]: Previous Sleep Cause: 0

Mar 22 16:24:40 Pasha kernel[0]: 11D beacon causing regdomain change to CC 840

Mar 22 16:24:40 Pasha kernel[0]: en1: 802.11d country code set to 'US'.

Mar 22 16:24:40 Pasha kernel[0]: en1: Supported channels 1 2 3 4 5 6 7 8 9 10 11 36 40 44 48 52 56 60 64 149 153 157 161 165

Mar 22 16:24:40 Pasha airportd[1469]: FastFinder scanning channels again

Mar 22 16:24:41 Pasha airportd[1469]: Could not find "tricktail" 

Mar 22 16:24:41 Pasha airportd[1469]: FastFinder scanning channels again

Mar 22 16:24:42 Pasha airportd[1469]: Could not find "asu" 

Mar 22 16:24:42 Pasha airportd[1469]: Already scanned all remembered channels for "deca15"; not found.

Mar 22 16:24:42 Pasha airportd[1469]: Could not find any preferred networks; trying broadcast requests..

Mar 22 16:24:43 Pasha kernel[0]: AFPSleepWakeHandler:  waking up

Mar 22 16:24:44 Pasha airportd[1469]: Broadcast requests also failed..

Mar 22 16:24:45 Pasha kernel[0]: AppleYukon2: 00000000,00000000 sk98osx_dnet - recovering from missed interrupt

Mar 22 16:24:45 Pasha airportd[1469]: Probing highest ranked networks via directed scan..

Mar 22 16:24:51 Pasha kernel[0]: AppleYukon2: 00000000,00000000 sk98osx_dnet - recovering from missed interrupt

Mar 22 16:24:56 Pasha kernel[0]: AirPort: Link Up on en1

Mar 22 16:25:12 Pasha com.apple.launchd[446] (com.apple.NetworkDiagnostics[1483]): Check-in of Mach service failed. Already active: com.apple.NetworkDiagnostic.agent

Mar 22 16:25:27 Pasha kernel[0]: AirPort: Link Down on en1

Mar 22 16:25:27 Pasha kernel[0]: AirPort: Link Up on en1

Mar 22 16:26:59 Pasha com.apple.launchd[1] (com.apple.backupd-wake[1472]): Exited with exit code: 1

Mar 22 17:34:09 Pasha kernel[0]: AFPSleepWakeHandler:  going to sleep

Mar 22 17:34:09 Pasha kernel[0]: hibernate image path: /var/vm/sleepimage

Mar 22 17:34:09 Pasha kernel[0]: sizeof(IOHibernateImageHeader) == 512

Mar 22 17:34:09 Pasha kernel[0]: Opened file /var/vm/sleepimage, size 2147483648, partition base 0xc805000, maxio 400000

Mar 22 17:34:09 Pasha kernel[0]: hibernate image major 14, minor 2, blocksize 512, pollers 4

Mar 22 17:34:09 Pasha kernel[0]: hibernate_alloc_pages flags 00000000, gobbling 0 pages

Mar 22 17:34:10 Pasha kernel[0]: AirPort: Link Down on en1

Mar 22 17:34:11 Pasha kernel[0]: 11D beacon causing regdomain change to CC 840

Mar 22 18:04:20 Pasha kernel[0]: en1: 802.11d country code set to 'US'.

Mar 22 18:04:20 Pasha kernel[0]: en1: Supported channels 1 2 3 4 5 6 7 8 9 10 11 36 40 44 48 52 56 60 64 149 153 157 161 165

Mar 22 18:04:20 Pasha airportd[1632]: No networks found on channels remembered for library

Mar 22 17:34:11 Pasha kernel[0]: System SafeSleep

Mar 22 18:04:20 Pasha airportd[1632]: Could not find "library" 

Mar 22 18:04:21 Pasha kernel[0]: hibernate_page_list_setall start

Mar 22 18:04:20 Pasha airportd[1632]: No networks found on channels remembered for asu

Mar 22 18:04:21 Pasha kernel[0]: hibernate_page_list_setall time: 170 ms

Mar 22 18:04:20 Pasha airportd[1632]: Could not find "asu" 

Mar 22 18:04:21 Pasha kernel[0]: pages 513246, wire 152910, act 236319, inact 2314, zf 1584, throt 0, could discard act 66856 inact 41061 purgeable 12202

Mar 22 18:04:20 Pasha airportd[1632]: Already scanned all remembered channels for "deca15"; not found.

Mar 22 18:04:21 Pasha kernel[0]: hibernate_page_list_setall found pageCount 393127

Mar 22 18:04:20 Pasha airportd[1632]: Already scanned all remembered channels for "Ike's Coffee Shop"; not found.

Mar 22 18:04:21 Pasha kernel[0]: IOHibernatePollerOpen, ml_get_interrupts_enabled 0

Mar 22 18:04:20 Pasha airportd[1632]: Could not find any preferred networks; trying broadcast requests..

Mar 22 18:04:21 Pasha kernel[0]: IOHibernatePollerOpen(0)

Mar 22 18:04:21 Pasha kernel[0]: writing 392572 pages

Mar 22 18:04:21 Pasha kernel[0]: image1Size 478000640

Mar 22 18:04:21 Pasha kernel[0]: all time: 22738 ms, comp time: 2731 ms, deco time: 0 ms, 

Mar 22 18:04:21 Pasha kernel[0]: image 921885184, uncompressed 1607974912 (392572), compressed 917248032 (57%), sum1 e4741e47, sum2 423fb6d8

Mar 22 18:04:21 Pasha kernel[0]: hibernate_write_image done(0)

Mar 22 18:04:21 Pasha kernel[0]: sleep

Mar 22 18:04:21 Pasha kernel[0]: Wake reason = EC LID0

Mar 22 18:04:21 Pasha kernel[0]: System Wake

Mar 22 18:04:21 Pasha kernel[0]: Previous Sleep Cause: 0

Mar 22 18:04:23 Pasha kernel[0]: AirPort: Link Up on en1

Mar 22 18:04:25 Pasha kernel[0]: AFPSleepWakeHandler:  waking up

Mar 22 18:04:27 Pasha kernel[0]: AppleYukon2: 00000000,00000000 sk98osx_dnet - recovering from missed interrupt

Mar 22 18:04:33 Pasha kernel[0]: AppleYukon2: 00000000,00000000 sk98osx_dnet - recovering from missed interrupt

Mar 22 18:04:37 Pasha com.apple.launchd[446] (com.apple.NetworkDiagnostics[1657]): Check-in of Mach service failed. Already active: com.apple.NetworkDiagnostic.agent

Mar 22 18:06:39 Pasha com.apple.launchd[1] (com.apple.backupd-wake[1636]): Exited with exit code: 1

Mar 22 18:15:47 Pasha Safari[997]: IPCClient: Server port 0 is invalid; looking it up again...

Mar 22 18:30:46 Pasha com.apple.launchd[446] (com.apple.NetworkDiagnostics[1698]): Check-in of Mach service failed. Already active: com.apple.NetworkDiagnostic.agent

Mar 22 18:31:00 Pasha kernel[0]: AirPort: Link Down on en1

Mar 22 18:31:00 Pasha kernel[0]: AirPort: Link Up on en1

Here are some errors from after running iStumbler

Code:

Mar 23 18:59:46 Pasha iStumbler[3826]: exception getting radio info: XML parser error:\n        Unexpected character a at line 1\nOld-style plist parser error:\n        Unexpected ';' or '=' after key at line 1

Mar 23 18:59:50 Pasha iStumbler[3826]: WARNING: deviceInquiryComplete with error: 56

Mar 23 18:59:51: --- last message repeated 43 times ---

Mar 23 18:59:51 Pasha iStumbler[3826]: exception getting radio info: XML parser error:\n        Unexpected character a at line 1\nOld-style plist parser error:\n        Unexpected ';' or '=' after key at line 1

Mar 23 18:59:53 Pasha blued[51]: *** Terminating app due to uncaught exception 'NSInvalidReceivePortException', reason: 'connection is invalid'

I've attached a screen grab from iStumbler - I guess that I should let it run for a long period of time.

I'll look at the Hardware Tests this weekend.

Thanks for the suggestions,
Brett

Should I just resign myself in having it looked at by Apple (It has an AppleCare agreement)?

Thanks,
Brett

Yeah - I think taking it to Apple is a good idea. It looks like the Airport card might be failing at certain points for some reason.

Before doing that, however, you should capture similar graphs from iStumbler running on other Macs so that you can see that the signal is only failing on that one machine.
I'm not sure how you can synchronize the graphs - maybe you need to look at the text logs from iStumbler to get the precise times that the signal fails.

Does anyone know what the following message means?

Code:

Mar 31 19:24:54 Craigelachie mDNSResponder[16]: NOTE: Wide-Area Service Discovery disabled to avoid crashing defective DNS relay 192.168.1.1:53

I updated the firmware in my wifi router, and haven't had the issue for a couple of days, and it just popped up again on my computer.

I found this in system.log. 192.168.1.1 is the dsl modem/router.

Thanks,
Brett

Quote:

Originally Posted by brettgrant99 (Post 526806)

Does anyone know what the following message means?

Code:

Mar 31 19:24:54 Craigelachie mDNSResponder[16]: NOTE: Wide-Area Service Discovery disabled to avoid crashing defective DNS relay 192.168.1.1:53

I updated the firmware in my wifi router, and haven't had the issue for a couple of days, and it just popped up again on my computer.

I found this in system.log. 192.168.1.1 is the dsl modem/router.

Looking at the Darwin source for for OS X 10.5.5, I see that that message comes from the function "uDNS_ReceiveTestQuestionResponse" in the file "mDNSResponder-176.2/mDNSCore/uDNS.c"
Here's a comment from that source code that explains what is happening:

Code:

// We know of bugs in home NAT gateways that cause them to crash if they receive certain DNS queries.

// The DNS queries that make them crash are perfectly legal DNS queries, but even if they weren't,

// the gateway shouldn't crash -- in today's world of viruses and network attacks, software has to

// be written assuming that a malicious attacker could send them any packet, properly-formed or not.

// Still, we don't want to be crashing people's home gateways, so we go out of our way to avoid

// the queries that crash them.

//

// Some examples:

//

// 1. Any query where the name ends in ".in-addr.arpa." and the text before this is 32 or more bytes.

//    The query type does not need to be PTR -- the gateway will crash for any query type.

//    e.g. "ping long-name-crashes-the-buggy-router.in-addr.arpa" will crash one of these.

//

// 2. Any query that results in a large response with the TC bit set.

//

// 3. Any PTR query that doesn't begin with four decimal numbers.

//    These gateways appear to assume that the only possible PTR query is a reverse-mapping query

//    (e.g. "1.0.168.192.in-addr.arpa") and if they ever get a PTR query where the first four

//    labels are not all decimal numbers in the range 0-255, they handle that by crashing.

//    These gateways also ignore the remainder of the name following the four decimal numbers

//    -- whether or not it actually says in-addr.arpa, they just make up an answer anyway.

//

// The challenge therefore is to craft a query that will discern whether the DNS server

// is one of these buggy ones, without crashing it. Furthermore we don't want our test

// queries making it all the way to the root name servers, putting extra load on those

// name servers and giving Apple a bad reputation. To this end we send this query:

//     dig -t ptr 1.0.0.127.dnsbugtest.1.0.0.127.in-addr.arpa.

//

// The text preceding the ".in-addr.arpa." is under 32 bytes, so it won't cause crash (1).

// It will not yield a large response with the TC bit set, so it won't cause crash (2).

// It starts with four decimal numbers, so it won't cause crash (3).

// The name falls within the "1.0.0.127.in-addr.arpa." domain, the reverse-mapping name for the local

// loopback address, and therefore the query will black-hole at the first properly-configured DNS server

// it reaches, making it highly unlikely that this query will make it all the way to the root.

//

// Finally, the correct response to this query is NXDOMAIN or a similar error, but the

// gateways that ignore the remainder of the name following the four decimal numbers

// give themselves away by actually returning a result for this nonsense query.

So it seems what it means is Apple's code has tested your router/modem and determined that it has buggy handling of DNS queries.

Here my lack of knowledge of networking is hitting me smack in the face.

Is this an issue with hardware, or NAT? After the last message, I am suspecting the dsl modem, which as I understand it, has a router in it too.

Is this something that can be fixed by pointing to different DNS servers, or with a firmware update to the modem, or do I need to replace hardware.

I will certainly be playing around with that dig command tonight.

Thanks for the research Hayne!

Brett

Quote:

Originally Posted by brettgrant99 (Post 526873)

Is this an issue with hardware, or NAT? After the last message, I am suspecting the dsl modem, which as I understand it, has a router in it too.

Most dsl modems don't have routers, but in any case, the issue appears to be the router's firmware.

Quote:

Originally Posted by brettgrant99 (Post 526873)

Is this something that can be fixed by pointing to different DNS servers, or with a firmware update to the modem, or do I need to replace hardware.

Pointing your Mac to a DNS server, either your ISP's or a public server, should take care of it.

Well, now I am having problems on all of my machines. I believe that the issue is with the wifi bit of the wifi router. Here is why:

90% of the time, if I plug in an ethernet cable, the connection works fine, even if the wifi doesn't.
100% of the time, if I plug the dsl modem in, it works correctly
The problem is always solved if I cycle the power on the router.

I guess that I am dissappointed with wifi routers. I have tried a DLink, Netgear, Linksys, and NewerTech, and all of them eventually have issues. The best one has been the NewerTech. When I first got it, it worked great, but now I find myself cycling the power on it daily.

I am wondering if it may be an issue with the NAT in the router, as when I have problems, I cannot ping the router, even though I can ping other computers on the network.

For example, the router is a DHCP server from 192.168.0.100-110, the router is 192.168.0.2. The dsl modem is 192.168.1.1. When I have the problem, I can ping connected machines in the 192.168.0.100-110 range, but not 192.168.0.2 or 192.168.1.1.

School's out in a couple of days, but current events lead me to believe that the issue is not with the actual laptop hardware.

Any suggestions?

Thanks,
Brett

If you've got neighbors with wifi routers, make sure you're not using the same channel as one of them. Most default to channel 6.

Already check other channels.

Thanks for the suggestion, though.

Brett

Solved - kind of

Well I got rid of the double-NAT issue and am using the M1000 modem for NAT, DNS, and DCHP.

The connectivity issue has gone away. There is now a substantial delay before any web queries start, but once they start, they go as expected. I don't know why, but it seems to be an issue with the modem.

I have found numerous posts from people complaining about the routing capabilities of the M1000, so I may set it as a bridge and let the wifi router handle the PPPoE bit. Perhaps during all of my free time.

Thanks for the help and suggestions.
Brett

Quote:

There is now a substantial delay before any web queries start,

This type of problem is almost always an issue with one of your DNS Servers.

Trevor

I've tried all kinds of hardware options and dns settings. The delay is always there, albeit slightly less if I take the wifi router out of the question.

The only constant is the modem. I have tried opendns, the isp's dns servers, different public dns servers, etc.

Brett

Do you own the modem, or does your ISP?

If they do, you might be able to swap it out.

I started renting mine from my ISP after the first two I bought went belly up before amortizing themselves.