Losing internet connection (Ethernet, cable modem)

Hi,
Lately (the past month or two), I am tending to lose my internet connection. (I never would before.) I connect via Ethernet to my cable modem. My ISP tells me that if I am getting 4 steady lights on my modem (with the 5th flickering), it isn't the modem. (I was thinking of replacing it.)
Rebooting the computer will fix it. One minute it's fine, the next it may have lost the connection. When I lose connection, Network Diagnostics* says my built in ethernet and network settings are ok (green). The rest will vary (going on memory here), ISP, may or may not be green, Internet and server will be definitely out, when this happens.
* I have dragged it out of wherever it was buried and have it now on my desktop. It is VERY convenient to check what is going on with my connection problems. (I guess I have created an applet?) I recommend this to all.
I am considering re-installing the OS (archive and install) but am hoping someone can offer some suggestions for me to try short of that.
Disk Utility and Tech Tool Deluxe don't indicate any problems. I can try the Apple Hardware Test. I am hoping this isn't a hardware issue as I cannot afford a new Mac or other repairs. I can live with rebooting if I have to.
Thank you.
John L

The colors refer to what Network Diagnostics shows. Network Diagnostics is an Apple app that pops up when Safari has trouble connecting. I don't use Safari but loved having Network Diagnostics pop up so I figured out a way to use it independently of Safari. I dragged it out of wherever it was buried, put it on my desktop where it became an app and I use it at will to see why I am not connecting.
It will show green, yellow or red as an indication of each aspect of the connection: built in ethernet, network settings, ISP, Internet and server (being Apple's server). Right now, all are green. When I can't connect, I'll have several going from server backwards that are red. If it can't figure out the status I get a yellow light.
When I've asked my ISP why I am getting disconnected, they said if all 4 lights of the modem are steady (and the yellow one flickering), which they always have been when I've been disconnected, then it isn't the modem or them. They have good tech support and I trust them.
I have replaced the modem once in the past and that fixed things. I may do it again.
So, I don't know. I haven't tried the Safe Mode approach yet. I'll see if I can do that.
Cheers,
John

Similar Messages

How to share internet connection from cable modem through built-in airport on imac?

I have a cable modem with ethernet going into imac. How can I share the internet connection using the iMacs built in airport with other computers that have airport cards?
I would love to put an ethernet router between the imac and the modem and share the internet connection using the iMacs built in airport with other computers that have airport cards as well.
Thanks!

The setup I had working is what I have connected to the internet now. A cable modem with one ethernet jack that plugs into the iMac. The airport from the iMac broadcast to my G5 with an airport card in it and received the internet connection. The PC received it the same way from the iMac but to a Netgear wireless adapter.
I messed things up recently adding a wired 4 port ethernet router between the iMac and the modem, so that the modem ethernet plugged into the router, and from the router, plugged into the iMac which then could receive the internet but no more airport connections to my other machines. Haven't been able to get it working since.

AE Lost Internet Connection through Cable Modem

I suddenly lost all internet connectivity. Here's the setup and issues:
-- Two computers, a Mini and a PowerBook, both lost connection to Internet
-- Motorola cable modem (using Comcast)
-- Airport Express is connected to modem via ethernet
-- I can connect directly to the cable modem with the computer via ethernet and I can get internet service; also, Comcast assured me I still have service
-- The two computers can connect to each other via airport; file sharing, iTunes streaming, etc., works as usual
-- I've done all the usual "unplug everything and restart" routines
-- Nothing was changed recently that I can think of - it just lost connection to the Internet.
Any ideas?
PowerBook G4 17 1.67GHz 1.5Gb Mac OS X (10.4.6)

I fixed it, but I don't know if it will solve the problem Ada had. I got a note from Comcast recently saying I needed to have my IP settings to be dynamic, by using DHCP. I had already made that change so didn't suspect that was the problem. However, after looking closely, I found some things to change.
If you're using Comcast, or a similar service, then this may fix it:
I first went out and washed my car, then came back in. I think that's an important step. I have a large car, so if yours is small, you may need to wash it twice, or wash it then wax it. Then go back inside and . . .
In Airport Admin Utility, select your base station, then Configure.
Switch to the Internet tab.
Make sure it's set to Configure using DHCP
Make sure DNS Servers, Domain Name, and DHCP Client ID are left blank (this is the step I hadn't done before).
Click Update and close the program and wait for your base station to reset.
This should fix it.

Airport Extreme Cannot see Live Internet Connection from Cable Modem

Hi,
When I run a cable directly from my cable modem to my MacBook everything works fine. In fact, that is how I am connected to the Internet right now.
However, when I run the same cable into my Airport Extreme (AE) and then connect my MacBook to the AE (wired or wireless), the AE reports a problem connecting to the Internet. This is a new situation as everything has been working fine for months. I have changed nothing in this set-up for it to stop working.
I can only assume the at the AE is broken: the Internet connection is live, it was working fine for months and then stopped working. Is there anything I should try before I throw the AE in the garbage?
Thanks in advance.

Welcome to the discussions!
It appears as if you may not be aware that cable modems must be completely reset whenever the device that they are connected to changes. The reason for this is that the cable modem "remembers" the device that it has been connected to. In your case, it's "remembering" your computer and looking for it when you plug it in to the AirPort Extreme.
You need to make your modem "forget" your computer. Here's how:
o Push the reset button on the modem if there is one on your modem
o Power the modem down immediately after you push the reset button
o Pull the battery in the modem if it's easily accessible
o Leave the modem powered down at least 20-30 minutes (Some ISPs take longer)
Power down the rest of your network as well.
After the power down period, start the modem first and let it run 3-4 minutes by itself
Then start the Airport Extreme (you may need to "hard reset" the device again to start over on the configuration) and let it run a few moments
Then start your computers one at a time
Please post back on your progress. Remember, if you need to connect your computer directly to the modem again, you must reset the modem again because it will "remember" the AirPort Extreme if you have reset it correctly.

Intermittent dropout of internet connection using cable modem

Hello all.
My connection drops out a few times a day. Only for a few seconds, but I suspect it caused problems with downloading a playlist from iTunes today, which is particularly frustrating; and it's unnerving at the best of times. My ISP is not very helpful about this. I know that one possibility is that I'm getting interference from other signals, but I don't know what I can do about that, so I'm wondering if anyone has any suggestions about something I can do from the Mac.
To clarify:
The message I get from my email client (Entourage) is CONNECTION TO THE SERVER FAILED OR WAS DROPPED.
My modem is a D-Link, connected through an ethernet cable.
Here's hoping! Thanks in advance,
Roger

I think your problem is either the ISP or your modem. Try resetting the modem by shutting everything down; modem and Mac for two minutes. Then power up the modem, wait two minutes, then power up the Mac. If the problem persists have your ISP give you a new modem (if renting it from them) or purchase a new one.

Intermitent Internet connection to Cable Modem

Internet connectivity was working great. Then I switched Internet access to DSL and thus converted Linksys WRG54G connection to a DSL modem. Due to poor speeds with the DSL, I have moved back to cable. Now the connectivity to the Internet drop from the Linksys router every few hours. Connectivity to the cable modem seems to be fine.
What reprogramming am I missing for the router. It is set up exactly as the direction require.
Thanks

Follow this link and if you are using to configure your router.

Cant get my KN8 Neo 4 -F to get an internet connection through cable modem.

I have a full signal since I checked with my other computer. I just built this system and I cant get a connection to the internet. Seems like the LAN isnt working.

I dont think it's a mobo problem.
There is something that went wrong setting up the conn.
Try disabling firewall... both windows and Nvidia
Open a command window ant type: ipconfig
Check what u get.
Is cable connected from modem to pc?
Are u using router?
Let us know plz.

Connecting to cable modem via ethernet hub

My old airport just died and I just began reviewing the capabilities of the airport express. Would it be possible to access a cable modem if I hardwire it into my ethernet network and plug another CAT 5 cable into the airport - giving me wireless access to the rest of the computers and printers on my network.

You cannot directly connect your cable modem to a spare port on your existing ethernet network. Not only will this not allow you to share your internet connection, but it will also significantly complicate file and printer sharing AND it will remove the all-important firewall protection that should be in place between your LAN and the internet.
Therefore, if you want to share a cable modem connection with both wireless and non-wireless computers on a LAN, the Airport Express is not the right product for you. You need to buy either an Airport Extreme Base Station, or a non-Apple wireless router (all of which are designed to also allow a connection to a cabled ethernet LAN).

MBP connects to internet directly via cable modem, but airport wifi not working

Today I came home to a broken wifi. I think Time Warner Cable had an outage in my area which confused my modem and airport router, but anyway. After a short while I was able to connect to the internet if I plug the cable directly from the modem to my laptop (which is how I am currently posting this question). But if I instead connect the cable to my airport and try to connect via my usual wifi network, I don't have any internet. Here is what I have tried:
- cycle cable modem several times
- hard reset as well as factory reset of Airport
- trying to connect the cable modem to the airport via both WAN and Ethernet entry, power cycling the Airport, waiting several minutes on each to see whether I get internet
- Using Network > Assistant to create a new location and network
Under airport utility, the status messages I get are as follows:
- Internet Connection (tells me to cycle my cable modem, which I have tried)
- No DNS Servers (I haven't touched any DNS addresses, but this has never been an issue that prevents me from connecting to wifi)
- Ethernet unplugged (since I'm using the cable to write this message...)
My hardware is:
- MBP early 2011
- ubee cable modem (standard issue from TWC)
- Airport Express 802.11n (2nd generation).
My laptop is able to connect to other wifi networks, so that is not the issue.
Any help or advice is appreciated.

...And now it all of a sudden works. However, as I can't delete this post I hope others who have had similar problems may have solutions for future issues.

Macbook Pro suddenly will not connect to the internet via ethernet cable.

I know this is a long shot... but I figured I would give it a try.
My macbook pro suddenly does not connect to the internet via ethernet cable. Please bear with me, as I am not very tech-savvy - I will try my best to describe the symptoms!
I connect to the internet via ethernet (we don't have wifi). It was working before I went to work, and when I came home I suddenly couldn't get anything to work (I know everyone says this, but I truly didn't mess with anything). Internet browsers just think for awhile and then turn up the 'You are not connected to the internet' error.
I went into my network preferences and curiously, the 'Ethernet' shows a green dot and says 'connected'. However it says 'Authentication server is not responding' underneath the last part that says '802.1X: WPA: eduroam' (I think that is my user profile).
When I go into my 'security' settings I can see that my firewall is off, so that shouldn't be causing any problems.
I've tried restarting the router and computer itself many times. Diagnostics just gets to a certain point and reports back 'Network Diagnostics cannot fix the current networking problems.' I've also tried switching to a different ethernet cable, and I tried both cables out on a PC laptop and it connected without issue. Additionally, I brought my macbook along to a friend's house and it connected to his wifi just fine, so the problem appears to just be with ethernet connections.
I know it's hard to troubleshoot this kind of thing without being there and having a look at the computer yourself, but any tips wouild be greatly appreciated.

As I mentioned above, I am not very tech savvy so I have no idea why a wireless protocol would be showing up there, I'm just listing everything I see in hopes that someone might know something I can try. This is why I am asking for help here - I'm not sure what has happened that has made me unable to connect, especially since it seemingly occured while nobody was using the computer.
I guess I should clarify that I'm not a total hillbilly- normally my firewall is set to 'on', but I set it to 'off' to try and troubleshoot the issues here as I was told that sometimes it can interfere with the computer's ability to connect to the internet. If this is not the case and firewall does not affect anything, I will turn it back on while I try to fix this.
I have tried the method you mentioned above a few times - I actually contacted my ISP earlier this week and they recommended resetting the router like that. They didn't mention any known network issues.

Airport time capsule losing Internet connection?

My airport time capsule is losing Internet connection but I still have wifi? Any suggestions?

It could be your modem, or other problem on the ISP's end. Try resetting your modem - power it down and let it rest for a few minutes, then power it back up again.
If it is a cable modem, also disconnect its coaxial cable - literally unscrew it and leave it detached while the modem is powered down.
Leave the TC powered up during that time.
After a sufficient amount of time has elapsed reconnect the cable and power up the cable modem. If you're still having trouble contact your ISP.
The possibility of a TC problem exists but the sort of failure you describe is not common. If all else fails perform a "hard reset" followed by reconfiguring the TC. Your Time Machine backups will not be affected.

***Time Capsule intermittently losing internet connection***

Hello, Here's the story:
My Time Capsule intermittently is losing internet connection. The light is green for 5-10 minutes at a time, then turns amber for 2 minutes and loses internet connection.
At first,..I thought it was the TC going bad. Went to my local Apple store and had it replaced under warranty.
Still,, the same situation was happening.
Then talked to AT&T (DSL) and they checked the connection. They deemed it was OK and possibly the modem going bad.
Went to Best Buy and purchased a new modem. Installed, put into Bridge Mode,...interenet working OK.
Still,...the same situation that it stays on for 5-10 minutes, then loses it for 2 minutes.
Any ideas? Could it still be the ISP (AT&T)?
Last thought,...my neighbor uses Uverse (AT&T) for his cable/ISP and he is expierincing cable/ISP outages ramdomly. I am using DSL (AT&T) too but through my phone line. Are the two possibly related?

You need to run the modem in router mode..
I would either bridge the TC or remove it completely because you need to get exact log info from the modem.
Do isolation test.. ie remove all phones and filters and other devices from your phone line. Reboot the modem.. and wait for restart to complete.
Copy out of the modem the full line stats, sync info and even better if you can get cli access and do some deeper level stuff.. (most of the tools I use are PC only.. ie dmt tools).
Then make sure the log is turned on and giving max info and watch your connection.. if it drops without anything happening on the modem,, then the ISP is having issues.. which is possible although connection of cable and adsl is loose or non-existent.
If it drops sync keep track of how often and the line stats, Particularly the SNR..
See if you have an rf noise source in the house.. more if you are interested.

WRT160N losing internet connection

Hello,
I have a router WRT160N and is randomly losing internet connection. I should reset at every 5-50 seconds but is unlikely to do this. I prefer to insert the internet in network card, instead reset it every minute.
I've reset the router, I've restore it to factory settings with no result.
Internet is OK, cable is OK, MTU is OK, routing table is OK. What isn't OK?

Click here and select the correct version of your router, download the firmware and upgrade it...It should help you get a stable connection...Change the MTU to 1400...

Losing internet connection every hour

Hi Guys
I replaced my Linksys router with an Airport Extreme 4th Gen about 2 weeks ago
I keep on losing Internet Connection when connected through a Wireless connection. This happens with my Windows 7 PC's, with my iPhone4 and with my iPad2. The connection with the AE is kept alive but the passthrough to the Internet does not work anymore. I have to reset my wireless adapter to reconnect and rebuild my internet connection.
Fyi,
My IPCONFIG result:
   Verbindingsspec. DNS-achtervoegsel: telenet.be
   Beschrijving. . . . . . . . . . . : Intel(R) Centrino(R) Advanced-N 6200 AGN
   Fysiek adres. . . . . . . . . . . : 00-27-10-48-22-38
   DHCP ingeschakeld . . . . . . . . : ja
   Autom. configuratie ingeschakeld : ja
   Link-local IPv6-adres . . . . . . : fe80::34a4:c702:47d:8663%1 3(voorkeur)
   IPv4-adres. . . . . . . . . . . . : 192.168.0.109 (voorkeur)
   Subnetmasker. . . . . . . . . . . : 255.255.255.0
   Lease verkregen . . . . . . . . . : woensdag 3 augustus 2011 20:20:02
   Lease verlopen. . . . . . . . . . : donderdag 4 augustus 2011 21:41:06
   Standaardgateway. . . . . . . . . : 192.168.0.1
   DHCP-server . . . . . . . . . . . : 192.168.0.1
   DHCPv6 IAID . . . . . . . . . . . : 352331536
   DHCPv6-client DUID. . . . . . . . : 00-01-00-01-15-02-48-56-00-24-BE-EB-D2-73
   DNS-servers . . . . . . . . . . . : 192.168.0.1
   NetBIOS via TCPIP . . . . . . . . : enables
Note that - when losing internet connection - my IPCONFIG result remains the same...
and the AE log (note the :38 my PC)
Aug 3 22:38:15    5    Rotated CCMP group key.
Aug 3 22:38:15    5    Deauthenticating with station 00:27:10:48:22:38 (reserved 2).
Aug 3 22:38:15    5    Disassociated with station 00:27:10:48:22:38
Aug 3 22:38:15    5    Associated with station 00:27:10:48:22:38
Aug 3 22:38:15    5    Installed unicast CCMP key for supplicant 00:27:10:48:22:38
Aug 3 22:38:16    5    Rotated CCMP group key.
Aug 3 22:39:18    5    Rotated CCMP group key.
Aug 3 22:46:05    5    Associated with station 00:27:10:48:22:38
Aug 3 22:46:05    5    Installed unicast CCMP key for supplicant 00:27:10:48:22:38
Aug 3 22:46:38    5    Associated with station 00:27:10:48:22:38
Aug 3 22:46:38    5    Installed unicast CCMP key for supplicant 00:27:10:48:22:38
Aug 3 22:47:37    5    Connection accepted from [fe80::34a4:c702:47d:8663%bridge0]:51949.
Aug 3 22:47:38    5    Connection accepted from [fe80::34a4:c702:47d:8663%bridge0]:51950.
Aug 3 22:47:41    5    Connection accepted from [fe80::34a4:c702:47d:8663%bridge0]:51951.
I really hope someone can help me out here.
I do not want to go back to my good old Linksys...

I have a similar problem with a new TC 2TB unit. I have ATT ADSL service using a Speedstream modem. PPPoE is setup on the TC and it works and connects. All features of the TC are working (wi-fi, Back to My Mac, Time Machine, etc...) and the light is solid green on the TC.
Periodically, the LED blinks amber and I've lost Internet access. The Speedstream modem shows all green lights. I have found that power cycling the Speedstream modem brings the TC back to solid green after about 2 minutes.
I am seeing this happen about once a day and it can happen overnight when there is no network activity. I am thinking that the lease on the IP address given by ATT expires and the TC does not know enough to reinitiate a connection. I have set the PPPoE Connection to Always On and experienced the problem. I have also tried setting the Connection to Automatic and set the Disconnect if Idle setting to Never.
Message was edited by: Dan Peterka

After a long in "stop" period, the internet connection (ethernet) doesn't work. before updating to mountain lion this problem didn't exist.

after a long in "stop" period, the internet connection (ethernet) doesn't work. before updating to mountain lion this problem didn't exist.

Gave up on the GUI. This script derived from http://blog.netnerds.net/2012/07/os-x-how-to-setup-nat-on-lion-and-mountain-lion / seems to work for me:
gwdev=en0 # This is my WiFi connection (has Internet connection)
targetdev=en1 # This is the USB to Ethernet adapter (to give Internet connection)
/sbin/ifconfig $targetdev down
/sbin/ifconfig bridge0 create
/sbin/ifconfig bridge0 up
/sbin/ifconfig bridge0 addm $gwdev
/sbin/ifconfig bridge0 $HOST_ADDR
/sbin/route add default -interface bridge0 -ifscope bridge0 -cloning
/usr/sbin/sysctl -w net.inet.ip.forwarding=1
/sbin/ipfw add 100 divert natd ip from any to any via $gwdev
/usr/sbin/natd -interface $gwdev -use_sockets -same_ports -unregistered_only -dynamic -clamp_mss -enable_natportmap -natportmap_interface $targetdev

Losing internet connection (Ethernet, cable modem)

Similar Messages

Maybe you are looking for