DNS Lookup Fail
 

Hey everyone,

My knowledge about software/hardware is very limited - so I hope that you understand my request.

I have a new Macbook Pro (os x 10.6.8) and I recently moved from Germany to Netherlands. Since almost the beginning I had troubles with my internet connection. It was very slow and unstable. I thought maybe it is because of the location of the router (1 floor above me). Turned out, my flatmate, 2 floors above me has no problems with the internet (Macbook Air) and with my iPhone 4 I also have no problems connecting to the wireless lan network.

I changed from Safari to Google Chrome and when the problems start, Google Chrome tells me the DNS lookup failed.

Some Details: My Macbook works fine at the university network, my iPhone works fine in my room, my other roommates do not encounter problems either. I connect via a router to the internet.

So I guess that I have somehow wrong network settings which causes the DNS Lookup fails. Strangely, I have days, when everything works fine, and days I can't barely connect to the Internet.
I'm now doing my Master studies here, and I can't run to the library every time my internet sucks.

I hope you guys can help me somehow - If you need more information, just tell me!

Thanks

Open Terminal.app and enter these commands:
Please post the output so we can see what's going on.

Mac DNS issues...yawn. Sort of wish Apple just get this right, they have been playing turkey with this for ages (esp. since moving over to mDNSresponder for all lookups in Snow) Mac OS X v10.6 uses the mDNSResponder process for unicast DNS (Domain Name System) functions, as well as Bonjour functions.

Also quick fix(test) is just to enter DNS servers manually in Network Prefs > Network Interface > Find DNS tab and enter 8.8.8.8 and 8.8.4.4 (Google DNS).
Also i woudl advise turning off IPv6 on your network interface as well.

Unless you're like me and have a functional IPv6 network.

Yes indeed SirDice, but OP have already said they are not using IPv6 ;-)
Oh the joys of IPv6 can't wait for Apple to get that all wrong too.

I am pretty pissed with Apple's network stuff overall. Something which is so fundamental to get right. I have to battle with AD "integration" on a daily/weekly basis and have to tweak the hell out of everything to get the Mac's to work only to have it all wiped out by an incremental "fix" grrrrrr

A little offtopic perhaps but my home network has been running IPv6 for years now. Never had any issues with any of my machines. Which is a mix of FreeBSD, Windows and OS-X.

Is the BSD box the DNS server, if so i can see why it all works for you. Just try and get IPv6 running on OSX Server BIND9 #fail but maybe i am just not skilled enough !

Yes, my FreeBSD box is doing DNS, but it runs the same BIND (maybe not the exact same version but I've used various versions). I see no reason why it shouldn't work on OS-X too, unless Apple broke it.

"Unless Apple broke it" well what do you think ;-)
Must admit we only did some basic testing on a network with Xserver IPv6 #failed to get it working right. So abandoned for the moment. Also *BSD is the king of networking IMHO.

Couldn't agree more :D

....So hence my frustrations with Apple and their ability to cock up networking. The mDNSResponder mechanism has a mind of its own !
Was excited to PF in Lion as well another great BSD firewall.

lo0: flags=8049<UP,LOOPBACK,RUNNING,MULTICAST> mtu 16384
inet6 ::1 prefixlen 128
inet6 fe80::1%lo0 prefixlen 64 scopeid 0x1
inet 127.0.0.1 netmask 0xff000000
gif0: flags=8010<POINTOPOINT,MULTICAST> mtu 1280
stf0: flags=0<> mtu 1280
en0: flags=8863<UP,BROADCAST,SMART,RUNNING,SIMPLEX,MULTICAST> mtu 1500
ether c8:2a:14:15:44:ff
media: autoselect (none)
status: inactive
en1: flags=8863<UP,BROADCAST,SMART,RUNNING,SIMPLEX,MULTICAST> mtu 1500
ether e0:f8:47:23:e6:e4
inet6 fe80::e2f8:47ff:fe23:e6e4%en1 prefixlen 64 scopeid 0x5
inet 192.168.1.79 netmask 0xffffff00 broadcast 192.168.1.255
media: autoselect
status: active
fw0: flags=8863<UP,BROADCAST,SMART,RUNNING,SIMPLEX,MULTICAST> mtu 4078
lladdr 70:cd:60:ff:fe:d3:31:54
media: autoselect <full-duplex>
status: inactive
MacBook-van-A-Tomano:~ atomano$ netstat -rn
Routing tables

Internet:
Destination Gateway Flags Refs Use Netif Expire
default 192.168.1.254 UGSc 16 0 en1
127 127.0.0.1 UCS 0 0 lo0
127.0.0.1 127.0.0.1 UH 2 19546 lo0
169.254 link#5 UCS 0 0 en1
192.168.1 link#5 UCS 2 0 en1
192.168.1.79 127.0.0.1 UHS 0 112 lo0
192.168.1.254 0:24:17:69:26:dc UHLWI 28 1022 en1 1195
192.168.1.255 link#5 UHLWbI 1 312 en1

Internet6:
Destination Gateway Flags Netif Expire
::1 ::1 UH lo0
fe80::%lo0/64 fe80::1%lo0 Uc lo0
fe80::1%lo0 link#1 UHL lo0
fe80::%en1/64 link#5 UC en1
fe80::e2f8:47ff:fe23:e6e4%en1 e0:f8:47:23:e6:e4 UHL lo0
ff01::/32 ::1 Um lo0
ff02::/32 ::1 UmC lo0
ff02::/32 link#5 UmC en1
MacBook-van-A-Tomano:~ atomano$ dig www.google.com

To be honest I have no experience with OS-X server at all. Never got around to it.

But yes, mDNSResponder is a bit weird. It's the same on FreeBSD with avahi, sometimes it works, sometimes it doesn't. And it doesn't seem to like IPv6 very much :(

Indeed this is massive issue and effects so many things. Since moving UnicastDNS to mDNSresponder things have only got worse for me. They have to get this right, it is key and bloody annoying. The trouble i have had to endure with Apple choosing .local for mDNS etc has pissed me off big time. I do not care if MS stole/borrowed/butchered this extension, it would have been easy to use .lan .loc or even .apple etc

You try getting an AD engineer to change anything, not easy and understand why.....having to set special sub-domains/OU for Mac Users is far from ideal and does not help integration.

Yep, it's one of the reasons why I advise people to never use .local as a TLD in their DNS. Changing a DNS zone to some other TLD is relatively easy but it quickly becomes a nightmare when Windows Active Directory is involved.

My home network uses .home as TLD. I've setup DHCP to connect with DNS to get DDNS. Works like a charm and I therefor have no need for mDNS.

Yes but most small business networks are always setup with .local it seems the only way low level MS engineers know how to do things. Also I have many SBS environments which only have 1 Domain and to change is serious PITA.

The annoying thing is that MS engineers do not get it. Recently had a new office that got a SBS2011 server installed for 40 PC's and 25 Macs. I sent a very detailed document to person deploying it and they basically went ahead and still used .local "as the wizard said to do it". Overall it has caused chaos, they did not setup DNS right & autodiscover so Outlook/Mail does not work right and have had to walk away from job as they were donkeys. A pity for the Mac dept as they have constant Login & Exch email problems, but i was subbed in on the job. #doh

As such i could have set it all up right but MS guy would not let me anywhere near server, "You are the Mac guy....deal with that side".

So any suggestions?

LOOK AT POST AND TRY MY SUGGESTION

"Also quick fix(test) is just to enter DNS servers manually in Network Prefs > Network Interface > Advanced if WIFI/AIRPORT Find DNS tab and enter 8.8.8.8 and 8.8.4.4 (Google DNS)."

And AIRPORT network settings should look like this : Notice IPv6 off.

Sorry, I seemed to have missed your post.

Your ifconfig and netstat outputs look fine so basic TCP/IP is working. I'm do seem to be missing the dig output though. That's to test your DNS settings.

When comparing settings keep in mind that AgentX uses 10.0.1.0/24 as his network while you use 192.168.1.0/24.

Ha me & SirDice got sidetracked and hijacked post oops we are very naughty !
But please try my suggestion, i have a feeling DNS requests are not being passed from machine to router correctly/or vice versa and hard coding DNS servers may help.

Before changing them I'd like to see it tested with dig. There's some malware for OS-X that changes your DNS settings. This will also result in slow internet.

I'd like to make sure you don't have it :D

dig www.google.comLast login: Fri Oct 7 13:24:20 on console
MacBook-van-A-Tomano:~ atomano$ dig www.google.com

I changed the DNS settings according to your recommendation. Did not solve it - with that I had no internet connection at all.

That's all? That doesn't look right... It should produce something like this:
It's possible your network location got corrupted somehow, let's try this:

That should reset a few things.

; <<>> DiG 9.6.0-APPLE-P2 <<>> www.google.co
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 35213
;; flags: qr rd ra; QUERY: 1, ANSWER: 4, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;www.google.co. IN A

;; ANSWER SECTION:
www.google.co. 2925 IN CNAME www3.l.google.com.
www3.l.google.com. 217 IN A 74.125.79.100
www3.l.google.com. 217 IN A 74.125.79.101
www3.l.google.com. 217 IN A 74.125.79.102

;; Query time: 41 msec
;; SERVER: 192.168.1.254#53(192.168.1.254)
;; WHEN: Fri Oct 7 19:14:14 2011
;; MSG SIZE rcvd: 110

MacBook-van-A-Tomano:~ atomano$

MacBook-van-A-Tomano:~ atomano$ ipconfig set en1 BOOTP
ipconfig_set en1 BOOTP failed: permission denied
MacBook-van-A-Tomano:~ atomano$ ipconfig set en1 DHCP
ipconfig_set en1 DHCP failed: permission denied
MacBook-van-A-Tomano:~ atomano$

As root obviously...

I.e. you need to precede those commands with 'sudo':

sudo ipconfig set en1 BOOTP

Actually, I was rather annoyed that the SBS 2011 network configuration wizard doesn't even let you specify the domain extension (a change from SBS 2003 - not sure about SBS 2008). And yup, even with the chaos it causes MS stubbornly still defaults to .local!! Why couldn't they use .sbs or anything else?

If they are using DNS and Domain hosting from a company that MS has hooks with, like GoDaddy, SBS will automatically configure split DNS (assuming they are NATing a private IP space to external public space) so that internal machines DNS lookups go the right way, and external machines also go the right way.

If you don't let the wizard configure both your internal and external DNS records, it sets up everything to work off the external IP range only - so you have to create a new zone for your public DNS zone in the SBS DNS, the manually create the three or four records for internal lookups with your private IP addresses, including Exchange autoconfig record, to get everything to work right. It's not hard if you do some digging around, but annoying because overall the level and completeness of automation in SBS is pretty good overall. But then again, that's the difference between MS and Apple - Apple sweats the details and MS is willing to live with "basically good enough"...

I hate those types - if your wrong or clueless, your wrong or clueless - it doesn't matter who points it out to you :rolleyes:

Has anyone found a solution yet? I'm having the exact same problem on a MacBook Pro 4,1 on OS X 10.7.4. My wifi works fine everywhere except at one cafe, when it worked the very first time I went and hasn't since. I only started going there after I was already on Lion, so I don't know if this is a 10.7 problem or an older MBP problem.

All I know is that it's frustrating as hell, because the wifi works for everyone around me and for my iPhone.

Create a new Location for this cafe', and see if the new Location works.

Trevor

DNS Lookup Fail
 

I have also run into this issue on a customer's computer at work. Customer is very angry that we have not been able to fix it.

Would like to note, I've tried to create a new location and erase locations and rename locations, and it won't save any changes I make.

Can freely surf around using DNS addresses, but every link you click on references the name, not the dns address, so clicked links fail.

I know DHCP is working correctly, but DNS names won't resolve.

Been researching for a while, and find many reports of the same problem, but no fix. I'm out of ideas.

Chuckie Chuck.