Dropping Internet connection

[rongold]

My G4 iMac (OS X 10.4.11) has a new problem. I leave it on 24/7. When I try to check email in morning, I find that the machine has disconnected overnight. When I check Network Status on Network PrefPane, it says that the Ethernet cable is not connected. The same problem occurs whenever I restart the computer. Problem is easily solved by clicking on Disconnect Button, and then reconnecting. But any idea why it has started happening?

[Paddy]

Ron, are you using a router or is the G4 connected directly to the modem? If using a router, are you using DHCP or have you assigned an IP manually? Is this cable broadband or DSL? Have you tried switching the ethernet cable itself? (they sometimes get flaky...)

[rongold]

I am using a router (Siemans Speedstream 6520), DSL connection, DHCP, and I have not tried switching Ethernet cable, but will do that and let you know.

[rongold]

Changing Ethernet cable between router and computer did not help. On restart, fails to connect automatically and Network Status indicates Ethernet cable is not connected. When I disconnect and re-reconnect, connection is made.

[chriskleeman]

Hi Ron,

This may be a stretch, but got any dust in there? Sounds to me that you might have a slight mechanical problem with the Ethernet port... take a Q-tip and a little alcohol and swab around inside the ports to clean the contacts... on both the computer and the router... if there's any kind of intermittent connection at either end the computer would show that it was disconnected...


HTH, and that it's really this simple, which it probably isn't...

Chris K

[Paddy]

Have you tried trashing your network preferences?

/Library/Preferences/SystemConfiguration/NetworkInterfaces.plist
/Library/Preferences/SystemConfiguration/preferences.plist

(that's the main Library, not the User one) Move these two preferences into the trash and then restart. You may have to redo some of your settings, though the default is usually a wired ethernet connection.

Also - have you power-cycled the router and the modem? Unplug both, wait about 2 minutes, then restart the modem and wait until the flashing lights settle down, then power up the router.

[rongold]

Cleaning Ethernet ports with alcohol on Q tip did not solve problem.
Power-cycling router-modem (Speedstream is combined router-modem) did not solve problem.

So, I backuped by User files with SuperDuper, re-booted from cloned external hard drive. I then cloned the external hard-drive (a recent clone of my internal hard drive) with SuperDuper back to the internal drive.

When I boot now, the machine connects to Internet automatically. I don't have a clue how I screwed up whatever preference files were corrupted, but re-cloning solved problem

Thanks for help.