[cmt]

I'm out of ideas, so I'm going to throw this one to the forum and see if anyone has an idea.

Safari and Mail, and IE have all stopped working, or at best, working at a pace you could time with a calendar.

If I open the terminal and ping a few sites, the response is nice and fast. If I try to use the internet from an application like safari, or Mail, the application times out, or works so slow as to be unusable.

However, World of War Craft plays fine.

A second Mac using the same router and cable modem has no problems at all.

I've checked permissions and run fsck, no problems.
I moved all the preference files out of the preference folder, and tried safari, and the problem remained.

It looks like the internet connectioni is fine (based on the response of the ping), so why won't anything load in safari or IE?

[Detrius]

What version of OS X are you running?

[tonyibook]

I kept on losing my internet on a random basis, although pings would work. It turned out to be Norton Parental Control. Every now and then it would block all traffic, and only a re-start would get it going again. In the end I removed Norton.

[cmt]

The iMac is running 10.3.8. There is no Norton or any other parental control software loaded.

I was thinking about loading up Virix and looking for a virus, but have not done that at this time.

[Big Mac]

There are no known OS X viruses at this point in time, so that's not the issue. I would reinstall the OS.

[Mithras]

Try a few more things.
First, check that you don't have any proxies entered in your Internet prefpane.
Next, at the Terminal, try a few things like
time curl http://www.google.com
time curl http://www.yahoo.com
time curl http://www.nytimes.com

and see whether curl can download a light, medium, and heavy page (respectively) in a reasonable amount of time.

Also, you can try telnetting to a mail server to send yourself some mail:
telnet smtp.yourisp.com 25
Then continue with the instructions on this page

[workerbee]

I've also recently started to run across a mysterious slowdown in my internet access. This only happens when I bring my PowerBook to the office, an equally fast ADSL connection at home (with the same provider) runs very fast... and stable.

I've started sniffing all traffic on my Airport, and have noticed things I don't understand:

There was the "living dead browser". Even after I quitted OmniWeb (and any other browser on my system), I still kept seeing how there was http traffic on port 80, trying to open macupdate content.

Other things I have no idea about are these strange calls that keep repeating over and over:

Code:
192.168.100.202.51457-205.188.009.084.05190: *.hv..
192.168.100.202.52551-080.074.142.073.00995: .....|....j..\..9DC1.......
192.168.100.202.51457-205.188.009.084.05190: *.hv..

064.233.171.109.00587-192.168.100.202.49457: ....-.J.^l<..@_cCl.H.3.`..r...."6$...97...K.....].
Y...g{(.K...202.49440-080.074.142.081.00995: .....ip..i.M...
192.168.100.202.49457-064.233.171.109.00587: ..........VT..8.u]>[email protected]..
192.168.100.202.49457-064.233.171.109.00587: .....M-.UN3,p...{..)6.C..w.
192.168.100.202.49457-064.233.171.109.00587: .....M-.UN3,p...{..)6.C..w.
192.168.100.202.49457-064.233.171.109.00587: .....M-.UN3,p...{..)6.C..w.
192.168.100.202.49457-064.233.171.109.00587: .....M-.UN3,p...{..)6.C..w.
192.168.100.202.49457-064.233.171.109.00587: .....M-.UN3,p...{..)6.C..w.
192.168.100.202.49457-064.233.171.109.00587: .....M-.UN3,p...{..)6.C..w.

(192.168.100.202 is my current fix local IP)

Then I noticed that our local AppleShare server generating traffic without me opening or requesting anything at all; stuff like
192.168.100.202.62025-192.168.100.XXX.00445: .....SMBr...............................PC NETWORK PROGRAM 1.0..MICROSOFT NETWORKS 1.03..MICROSOFT NETWORKS 3.0..LANMAN1.0..LM1.2X002..DOS LANMAN2.1..Samba..NT LANMAN 1.0..NT LM 0.12.
192.168.100.XXX.00445-192.168.100.202.62025: ...U.SMBr...............................2....A.... ..........V.V..>.......-a...!AJ.......0
......................\..........U.n.i.x...S.a.m.b .a.............................
192.168.100.XXX.00445-192.168.100.202.62025: .....SMBs..................................^..W.i. n.d.o.w.s. .5...0...W.i.n.d.o.w.s. .2.0.0.0. .L.A.N. .M.a.n.a.g.e.r...W.O.R.K.G.R.O.U.P..
is turning up out of the blue -- but then maybe this is Rendevous-related. (Is there a way to turn off Rendevous BTW?)

Anyone have a clue as to what could be going on? The slowdown, when it happens, is really quite extreme, as cmt noted -- so much so that I repeatedly thought it was completely dead. Restarting the PowerBook does not help and is extremely slow after login.

Thanks!

[Gavin]

My first guess would be a lookupd / DNS issue.

just for the hell of it try this:

sudo lookupd -flushcache

that will flush the DNS cache that safari and other apps use.

things like ping can bypass it

You'll have to restart safari after doing this.

I would also try 'renew DHCP lease' in the network control panel.

also try to telnet on the http port in the terminal, that will give you a clue if it's a port thing or an app thing or a DNS thing, etc.

telnet domain.com 80

you should see something like this:

Trying 261.25.44.41...
Connected to domain.com.
Escape character is '^]'.


then type:

get /

that should get the home page.

[cmt]

Thanks for the hints.

It gets stranger. The morning after I posted the question, the problem went away. Now tonight, it is back, but worse. Now nothing works. or at best, works very very slow.

Before I could still ping things. Now it will not even ping. I can ping the router, but no web sites.

I tried the things listed in the last post (deleting the cache, etc) and still nothing.

Any suggestions on why this issue would come and go like this?

[Gavin]

The nuclear option: push the reset button on your router.

Go through the router settings first. Write down any usernames,. passwords, port forwarding, etc.

[RayK]

This is the EXACT SAME problem a friend of mine has. He has a Mini, latest of everything, and it does this comes and goes. Maybe I can get him to try some of these things... or post here.

[frankiec]

Have you tried inquiring here?

[nonhuman]

Originally Posted by Gavin

My first guess would be a lookupd / DNS issue.

Yeah, definitely sounds like a DNS issue to me. When you ping things are you pinging them by IP address or DNS entry? Try both, does it make a difference?

If you have manually set your DNS servers, try removing the first one(s) from the list. It's possible that it has a problem and the reason things are going so slow is that every time you try to look up a DNS entry it has to first wait for the request to the first server to time out. If you don't have them manually set, try getting some DNS server addresses and putting them in.

Also, check with your ISP and see if they're having any problems or scheduled maintenance. This would probably be a good thing to try first since if it's their fault you could try a million different things on your end and never learn anything.

[akuma-x]

Are you on Comcast by any chance?
If so Comcast has been having global DNS issues for a few days now.

[RayK]

My friend's on comcast. Hopefully that's the problem.

[cmt]

First off, many thanks to all the Mac community for responses to my original question. I always learn something new when I ask for help in these forums.

The problem was not with my machine, but with Comcast's DNS servers. As one of the replies noted, they have had three major outages of their DNS capability in the last week. All three coincide with the times my son�s Mac could not get to any internet services accept World of WarCraft.

I determined that the other Mac in our home was not affected because there was an alternative DNS server address manually entered into the network configuration. Since the working machine was a much older Mac that had been upgraded (OS wise) several times, I suspect that address was a leftover from some previous setup. My son�s machine had no alternative DNS addresses. When I added a couple to his network configuration, his machine was back in action. I must assume that WoW does not use DNS services to find the battlenet servers, and that is why it could connect.

The Comcast DNS outage has a lot of people very unhappy (if you read their forums anyway), and I heard that companies like Dell were swamped with calls because people thought they were having hardware issues. Comcast really has some egg on their face, since this happened three times in a week, and, according to their one posts, they still have not specific diagnosis as to what happened.

Anyway, Thanks again everyone!

[OreoCookie]

You mention your son. Does he use Bittorrent? In my experience, bittorrent can easily make a network connection unusable. When I visit my parents from time to time, I always have to ask my brother to stop any downloads before being able to access the internet.

Just an idea.

[cmt]

No Bittorrent. He wanted to download it, but I would not allow it. I'm sure it has many legit uses, but he wanted to download pirate videos. Perhaps I'm a little old fashioned, but that sounded to me like saying "sure son, go steal stuff".

He knows the machine is fair game (a family agreement), and I check it every now and then to see what he has loaded. It has been happy as a clam using the other DNS servers.

[OreoCookie]

Well, if he's half-smart, he's using it anyway. That's what clogs up networks quite efficiently. I would double check and show him Limewire. You can limit the bandwidth there.