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Mxdina6285
11-07-2006, 06:12 PM
I have a linksys wireless WRT54G router. At home i have 2 macs and a macbook. Ever since i started using this router i have been losing internet connection on my imac and have to reboot and reconnect the cables. But i've never had any problems with my macbook using linksys router and the internet is very fast. sometimes i have to reboot the router 2-3 times a day.
Is there some configuration problem? Or do I need a new router? If this is something that can be solved, can someone please give me more detailed instructions because I know next to nothing about this. thanks.

toppledwagon
11-19-2006, 11:19 AM
It could be the physical location of the router and the iMac. Maybe there is a microwave in between the two (or in a range that could disturb the wireless connection.) Maybe you have a 2.4Ghz cordless phone near the iMac (and when it's in use is when you have to reboot.)

Since the iMac is (probably?) stationary, I'd highly suggest running ethernet to it.

-Dave

pogle
11-20-2006, 07:39 AM
I have a very similar problem with a relatively new iMAC. After using the iMAC for several months with no problems at all on a wireless Linksys network, it has started to "lose the internet connection" even though the Airport sees the network and shows ample signal strength. For the first week or two, restarting the iMAC would revive the ability to surf the internet, though often the internet would get "lost" again after the iMAC went to sleep and was awakened. Recently, the internet connection has been unrecoverable with any rebooting, etc. Wiring the connection directly to the network does not help.

The REALLY ODD part of this is that email continues to work fine (sending and receiving), plus I can access the iMAC from the other machines (PCs) on the nework wirelessly (or wired). No recent other changed to the network, wireless devices, phones etc. have been made. The PCs, MAS drives and other net devices work fine. The MAC shows up properly in the DHCP dtable of the router - I can even log into the router directly from the MAC. It just seems to be a problem with the browser handling on the iMAC that is the problem. I am mainly a PC person, not a MAC expert, but I cannot see any obvious problems.

I spent over 90 minutes with Apple support on Friday, which included removing and rebuilding the airport connection, downloading a copy of Firefox to see if there was a problem with Safari (same result), rebooting the router, and a number of other efforts, all without solving the problem. The tech finally said the next step was to reload the OS (Arggh - this is a MAC, I told him, not a PC).

While pondering the potential grief involved in reloading the OS (and all the data), the MAC began working by itself again on Saturday, (wirelessley, no less), but by Sunday, had gotten stupid again.. Same issue - I can access the local network fine, send and receive email, but neither Safari nor Firefox thinks it has an internet connection, even though the mail program (and Airport) does.

I'm stumped. I am definitely not convinced reloading the OS will do anything but wast a lot of time. Any ideas would be appreciated....:mad:

Paul

hayne
11-20-2006, 10:46 AM
I can access the local network fine, send and receive email, but neither Safari nor Firefox thinks it has an internet connection, even though the mail program (and Airport) does.

That would sound like a DNS problem. Email is working because the mail server address is resolving properly since it is at your ISP, but other hostnames are probably not resolving.

Check if you can access web sites via their IP addresses instead of hostnames. If IP addresses work then you have a DNS problem and may have to enter the DNS servers for your ISP in the Network Preferences.

E.g. instead of trying http://www.apple.com
try: http://17.254.0.91

pogle
11-20-2006, 11:23 AM
That would sound like a DNS problem.


Hayne,

Sounds very plausible - I will try it when I get home this evening. What would likely cause such an intermittant problem like this.. something on my network?

Also, I know how to flush the cache on a PC, but not a MAC ... what's the equivalent version of the PC RUN command?

Paul

hayne
11-20-2006, 11:41 AM
What would likely cause such an intermittant problem like this.. something on my network?
More likely to be a problem with the DNS servers at your ISP.

Also, I know how to flush the cache on a PC, but not a MAC ... what's the equivalent version of the PC RUN command?

Easiest thing to do is probably to switch between two "locations" in Network Preferences. (Create a second location with all network things disabled)
Note that you can do this via the "Location" submenu in the Apple menu.

On the command-line, you can use 'lookupd' - read 'man lookupd'

pogle
11-20-2006, 12:22 PM
Hmmm... Well I suspect the problem may have something to do with the "Location" feature in the MAC. I didn't (don't still) understand the purpose of this and have added a couple "locations" (Home, Big-Mac, etc.) but the actual physical location of this machine is fixed, vs. dial-up ISPs for a laptop.

Even though "Automatic" is checked, maybe I should clear out all but one "Location" ???

Also, for us MAC newbies, how do you get to a "command line" on a MAC?

P.

pogle
11-20-2006, 12:28 PM
More likely to be a problem with the DNS servers at your ISP.


After thinking about your comment above...

... Actually, I am hitting the same sites with several PCs on the same wireless network as the MAC, and at the same time, so would seem unlikely an ISP issue (to me at least)....

... and these are mainstream sites, lioke google, yahoo, etc. The problem must be local to the machine, somehow, like the cache or something in the config for the browser(s)...

hayne
11-20-2006, 06:06 PM
Also, for us MAC newbies, how do you get to a "command line" on a MAC?
See this Unix FAQ (http://forums.macosxhints.com/showthread.php?t=40648)

pogle
11-21-2006, 12:55 PM
Thanks..

Here's an update. I tried the flushcache, but no joy. Then I called Apple Tech support back ... after about an hour, the tech escalated it to a senior product specialist. After about an hour with him, the theory was that it must be a DNS problem but the problem must be with the ISP and that there was no way it was a problem with the iMAC. Since everyother PC in the house is working, I don't think that it is an ISP issue. The next thing I plan to try is giving the iMAC a static address and plug in the ISP's alternate DNS numbers.

Somehow, I don't think you'll see my iMAC episode on any Apple commercials anytime soon....

hayne
11-21-2006, 01:02 PM
Note that 'lookupd' has an interactive mode (via the "-d" option) that you can use to test the DNS handling etc. (read the man page about it).

Another thing to try would be to install the 'dnstracer' utility from Fink and see what it tells you about your DNS availability.

pogle
11-21-2006, 02:57 PM
Hayne - thanks will do when I get home tonite. In the interim I am finding a whole lot of frustrated mac users with the same or very similar problems with a Linksys WRT54G (like me)... see here:

http://garrickvanburen.com/archive/how-to-set-up-a-linksys-router-with-mac-os-x

hayne
11-21-2006, 04:16 PM
I saw a note today on the Macintouch site about how a recent firmware upgrade apparently made a Linksys router incompatible with anything but Windows clients for some unstated reason.

pogle
11-21-2006, 07:24 PM
Well it appears that the problem on the iMAC was resolved by updating the DNS addresses in the Linksys router to the current ones used by BellSouth (the ones that show up in the modem) - they had recently changed. Now why the PCs on the network always worked with the old DNS servers (as well as the new ones) is a real question.

Anyway... we'll see how long this works. Thanks for all the help and advice.