[bleachout]

All of a sudden my OS 10.2.4 machine can't find the Yahoo.com server. It has no trouble with anything else and other machines on my network can find yahoo just fine. Any ideas? Thanks for the help!

Mike

[Jerommeke]

Can it be you already visited the Yahoo page before the problem occurred? A fresh reboot would most commonly solve those problems, if it isn't your DNS-server which isn't working (nothing on your system side, in that case it would be on the side of your ISP)

[bleachout]

Originally posted by Jerommeke:
Can it be you already visited the Yahoo page before the problem occurred? A fresh reboot would most commonly solve those problems, if it isn't your DNS-server which isn't working (nothing on your system side, in that case it would be on the side of your ISP)

Rebooting doesn't help. I'm behind a router and a pc can find yahoo just fine.

Mike

[bzImage]

same thing here..

my ibook with 10.2.4 cant find yahoo.com but the funny stuff its that if i do a nslookup from a terminal i get the address of yahoo with no problems..

Does darwin has a nameserver cache (like solaris ndc) or something ?

its not my dns server because my windows pc can find yahoo with no problems.

[Robo-X]

If you are using Airport it's problem with your ISP and Apples airport settings.
The MTU packets are too big and are not getting send through.

Open up the terminal and write ifconfig.

You should get a list with one or two ports. en0 is usually the built in ethernet. en1 or en2 the Airport. All of them are set to 1500.

To change the packets in the terminal enter
sudo ifconfig en1 mtu 1490

This should lower the packet size and make it connect properly.

//Rob

[bzImage]

Yes im using airport but this problem its not ISP related, nslookup works just fine, and this only its happening with yahoo.com domain no other domain, i just reinstall (partition and format first) 10.2.0, applied the combined update and still no yahoo.com resolution.

Here are some basic tests:

--- cut here

% nslookup
Default Server: deepgreen.demon.com.mx
Address: 192.168.1.1

> www.yahoo.com
Server: deepgreen.demon.com.mx
Address: 192.168.1.1

Non-authoritative answer:
Name: www.yahoo.akadns.net
Addresses: 66.218.71.88, 66.218.70.50, 66.218.71.92, 66.218.71.93
66.218.71.86, 66.218.71.89, 66.218.71.80, 66.218.71.87, 66.218.71.90
66.218.71.91, 66.218.70.49, 66.218.71.81, 66.218.70.48
Aliases: www.yahoo.com

ok, but what happens when i ping it ?

ping www.yahoo.com
ping: unknown host www.yahoo.com

What ???

Darwin gethostbyname() its not using the resolver funcions ????

this seems really strange ..

[Robo-X]

It has nothing to do with the DNS. The DSN server works fine but the TCP packets are too big and are not sent properly.

Use the command I wrote in my previous post and post back. No restart required.

But you might have a problem somewhere else. When I tried ping www.yahoo.com it returned 64.58.76.226. It looks like your not connected properly as your IP shows a local ip. 192.168.1.1 are LAN ips.

//Rob

[bzImage]

|It looks like your not connected properly as your IP shows a local ip. 192.168.1.1 are LAN ips.

192.168.1.1 its my BSDi server doing NAT, so it dont matter if it has a RFC1819 address, on the other network card it has internet ip address

bash-2.05a# ifconfig en1 mtu 1490
bash-2.05a# ping www.yahoo.com
ping: unknown host www.yahoo.com

When you say that the packets are not transmitted what packets are you refering to ?

The resolver packets ?

The http packets ?


The problem seems to be the resolver but a tcpdump shows my machine doing the question to my dns and my dns replying

here its a cut and paste from a tcpdump session

----
16:50:12.812818 192.168.1.218.49231 > deepgreen.demon.com.mx.domain: 46091+ A?
www.yahoo.com. (31)
16:50:12.816497 deepgreen.demon.com.mx.domain > 192.168.1.218.49231: 46091| 14/
11/0 CNAME[|domain] (DF)
16:50:12.817594 192.168.1.218.50981 > deepgreen.demon.com.mx.domain: S 347855546
9:3478555469(0) win 40000 <mss 1460,nop,wscale 0,nop,nop,timestamp 2372166307 0> (DF)
16:50:12.823365 deepgreen.demon.com.mx.domain > 192.168.1.218.50981: S 227779172
5:2277791725(0) ack 3478555470 win 5792 <mss 1460,nop,nop,timestamp 58832827 237
2166307,nop,wscale 0> (DF)
-----

192.168.1.218 its my ibook, deepgreen.demon.com.mx, its my house bsdi server running bind 9.x, and if the packets are too big, why this only happens with yahoo ?????????


cut here---

# nslookup www.google.com
Server: deepgreen.demon.com.mx
Address: 192.168.1.1

Non-authoritative answer:
Name: www.google.com
Address: 216.239.33.99

bash-2.05a# ping www.google.com
PING www.google.com (216.239.33.99): 56 data bytes
64 bytes from 216.239.33.99: icmp_seq=0 ttl=49 time=10.479 ms
64 bytes from 216.239.33.99: icmp_seq=1 ttl=49 time=14.246 ms
^C
--- www.google.com ping statistics ---
2 packets transmitted, 2 packets received, 0% packet loss
round-trip min/avg/max = 10.479/12.362/14.246 ms

cut here--

Strange, really strange..

[Robo-X]

Type in ifconfig and post the results here.

//Rob

[bleachout]

Originally posted by Robo-X:
Type in ifconfig and post the results here.

//Rob

That solution you posted didn't work for me either. here's what i get when i use ifconfig

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,MULT ICAST> mtu 1500
inet6 fe80::203:93ff:fe58:41f6%en0 prefixlen 64 scopeid 0x4
ether 00:03:93:58:41:f6
media: autoselect (none) status: inactive
supported media: none autoselect 10baseT/UTP <half-duplex> 10baseT/UTP <half-duplex,hw-loopback> 10baseT/UTP <full-duplex> 10baseT/UTP <full-duplex,hw-loopback> 100baseTX <half-duplex> 100baseTX <half-duplex,hw-loopback> 100baseTX <full-duplex> 100baseTX <full-duplex,hw-loopback>
en1: flags=8863<UP,BROADCAST,SMART,RUNNING,SIMPLEX,MULT ICAST> mtu 1500
inet6 fe80::230:65ff:fe0a:6052%en1 prefixlen 64 scopeid 0x5
inet 192.168.0.9 netmask 0xffffff00 broadcast 192.168.0.255
ether 00:30:65:0a:60:52
media: autoselect status: active
supported media: autoselect

[Robo-X]

If you only use the Aiport card to connect to the Internet open up the Network pref pane. Create a new Location called Home or Aiport or what ever you want. Click on the Show pull down menu and select Network Port Configurations. Deselect all ports except the Airport. In the show pull down menu there should be now only the Airport and Network Port Configurations. Select Airport and setup the PPP and other settings. When you are finished Click on the Apply Now.

Open up the terminal and enter this command:

sudo ifconfig en1 mtu 1490

Enter your password when asked for it. Try connecting to yahoo.com.

You can also try entering the ip address for Yahoo in the browser. If it works then there is something else blocking access to yahoo for you.

//Rob

[bleachout]

Originally posted by Robo-X:
If you only use the Aiport card to connect to the Internet open up the Network pref pane. Create a new Location called Home or Aiport or what ever you want. Click on the Show pull down menu and select Network Port Configurations. Deselect all ports except the Airport. In the show pull down menu there should be now only the Airport and Network Port Configurations. Select Airport and setup the PPP and other settings. When you are finished Click on the Apply Now.

Open up the terminal and enter this command:

sudo ifconfig en1 mtu 1490

Enter your password when asked for it. Try connecting to yahoo.com.

You can also try entering the ip address for Yahoo in the browser. If it works then there is something else blocking access to yahoo for you.

//Rob

Hey thanks for trying to help. I tried your solution above and it also didn't work. I even deleted Airport a couple times and nothing solved the problem. i am able to get to yahoo when typing in their IP address though. Any more thoughts? Thanks again!

Mike

[Robo-X]

OK try this workaround.
Open up NetInfo Manager (you find it in Applications/Utilities).
Click on the lock at the lower left corner.

Click on Machines in the list. And select localhost. Duplicate it and change the ip address 127.0.0.1 to the yahoo ip.
Change the Localhost copy to www.yahoo.com.
Chahnge ./local to ../network

Click on the localhost again and when asked to save changes save it.It will ask you two times I believe.

Now try to ping www.yahoo.com in the terminal.

//Rob

[bzImage]

mm.. not a real solution but i do this:

on terminal

sudo echo -e "66.218.71.92\twww.yahoo.com" >> /etc/hosts
sudo echo "hostresorder local bind" >> /etc/resolv.conf


This its not a good solution since yahoo.com dont use just 1 ip address, they use several (via akadns.com) and this makes the site faster to load instead of going just to 1 ip address.

bad, very bad, i dont know why this its happening.. strange stuff..

i think that i will need to setup a cache nameserver on the osx just to resolve yahoo ..

[gatorparrots]

Flush the lookup cache of cached DNS entries:
lookupd -flushcache

If that doesn't work, try restarting the lookup daemon altogether:
sudo kill -1 `cat /var/run/lookupd.pid`

[bleachout]

Originally posted by gatorparrots:
Flush the lookup cache of cached DNS entries:
lookupd -flushcache

If that doesn't work, try restarting the lookup daemon altogether:
sudo kill -1 `cat /var/run/lookupd.pid`

Neither of those worked. This is very strange.

[Robo-X]

Originally posted by bzImage:
mm.. not a real solution but i do this:

on terminal

sudo echo -e "66.218.71.92\twww.yahoo.com" >> /etc/hosts
sudo echo "hostresorder local bind" >> /etc/resolv.conf


This its not a good solution since yahoo.com dont use just 1 ip address, they use several (via akadns.com) and this makes the site faster to load instead of going just to 1 ip address.

bad, very bad, i dont know why this its happening.. strange stuff..

i think that i will need to setup a cache nameserver on the osx just to resolve yahoo ..

I believe you should use NetInfo Manager to change hosts config as OS X doesn't really support the hosts file and it might totally take that functionality away in a future update.

//Rob

[bzImage]

workaround..

1. i remove the yahoo.com references on my /etc/hosts file

2.- edit /etc/hostconfig, change DNSSERVER=-NO- to DNSSERVER=-YES-

3.- edit /etc/resolv.conf and leave only this line: nameserver 127.0.0.1 UPDATE: CHANGE THE DNS ON THE NETWORK PREFERENCES OTHERWISE ON THE NEXT REBOOT THE /etc/resolv.conf wil be overwritted by the one configured on network preferences.

4.- edit /etc/named.conf and add the following lines below this line:
// query-source address * port 53;
Add:
forward only;
forwarders {
<ip_address_of_your_original_DNS_server>;
};

Note: step 4 its optional, this still works without this step but this way the dns calls will be forwarded to your local or ISP DNS, therefore faster resolution.

5.- reboot

what are we doing ? setting up a cache nameserver..

Does name resolution to yahoo works now ? yes..


It stills bother me because i dont see the need of a extra process just to resolve the name of one domain..

[gatorparrots]

Originally posted by Robo-X:
I believe you should use NetInfo Manager to change hosts config as OS X doesn't really support the hosts file and it might totally take that functionality away in a future update.

//Rob

Actually, as of 10.2.x, FFAgent is included in the default lookup order ahead of NetInfo Agent (NIAgent). In other words, /etc/hosts entries are read before NetInfo machines entries.

[hudson1]

Same problem for me -- can't connect to 'www.yahoo.com' with my eMac (10.2.4) using any browser and connected via a cable modem to the internet (no Airport). I also tried 'lookupd -flushcache' both as admin and as root without success. Interestingly, if I launch Classic I can connect to 'www.yahoo.com' without problem using the OS 9 version of IE. One thing I haven't tried but will when I get home is to turn off the Firewall in System Preferences to see if that has any effect.

[2far]

It might be a problem with dangling CNAME records from Akamai (Yahoo and Apple are examples for that). This is information from Menandmice (makers of QuickDNS) - they are investigating the problem.

Solution (attempt): set a different DNS in your network preferences (from someone who does not have the problem).

You can set any DNS.

[bleachout]

Originally posted by 2far:
It might be a problem with dangling CNAME records from Akamai (Yahoo and Apple are examples for that). This is information from Menandmice (makers of QuickDNS) - they are investigating the problem.

Solution (attempt): set a different DNS in your network preferences (from someone who does not have the problem).

You can set any DNS.

Where do i find DNS addresses? Specifically my DNS server that my ISP uses? Thanks for the help!

Mike

[bzImage]

Originally posted by bleachout:
Where do i find DNS addresses? Specifically my DNS server that my ISP uses? Thanks for the help!

Mike

open a terminal window

type

nslookup

at the > prompt type:

set type=ns[enter]
domain_or_your_isp[enter]

for example:


> set type=ns
> prodigy.net
Server: localhost
Address: 127.0.0.1

Non-authoritative answer:
prodigy.net nameserver = ns1.flash.net
prodigy.net nameserver = dnsmaster.prodigy.net
prodigy.net nameserver = dnsmaster2.prodigy.net
prodigy.net nameserver = ns2.flash.net

Authoritative answers can be found from:
ns1.flash.net internet address = 207.115.62.38
dnsmaster.prodigy.net internet address = 207.115.62.76
dnsmaster2.prodigy.net internet address = 207.115.62.101
ns2.flash.net internet address = 207.115.62.124


so prodigy.net has 4 dns servers and their ip addresses are 207.115.62.38,207.115.62.76,207.115.62.101 and 207.115.62.124

type "exit" to exit the nslookup utility.

But i insist, the problem its not the DNS server..

[hudson1]

As many have suspected, this is a problem that has it's roots right in the system software.
The good news:

OS 10.2.5 has solved the problem.