I have connected my time capsule to motorola SG6580 modem via ethernet. I have a wireless network on the motorola and a wireless network from the time capsule. I get duplicate IPs error messages sometimes. How do I fix?

Question

Level 1

8 points

I have connected my time capsule to motorola SG6580 modem via ethernet. I have a wireless network on the motorola and a wireless network from the time capsule. I get duplicate IPs error messages sometimes. How do I fix?

I have connected my time capsule to motorola SG6580 modem via ethernet. I have a wireless network on the motorola and a wireless network from the time capsule. I get duplicate IPs error messages (no connection) sometimes when trying to connect devices to the wireless network. How do I fix? Sometimes devices cannot connect to the network because of conflicting IPs. I look on the Motorola and every device has a unique IP assigned but occasionally a device has taken the IP of another device. I have been writing down all the devices and the IPs they have been using. It happens more with PCs than Macs, ipads or iPhones.

MacBook Air, OS X Yosemite (10.10.2)

Posted on Mar 23, 2015 8:37 PM

Reply

Answer 1

Best reply

Bob Timmons

Community+ 2024

Level 10

159,272 points

Mar 23, 2015 8:49 PM in response to papaggaz

If the Time Capsule is set up correctly in bridge mode, then it is the responsibility of the Motorola modem/router to provide the correct IP address assignments for all devices on the network.

Check to insure that the Time Capsule is correctly set up to operate in bridge mode as follows:

On your Mac, open AirPort Utility

Finder > Applications > Utilities > AirPort Utility

Click on the Time Capsule icon, then click Edit in the smaller window that appears

Click the Network tab at the top of the next window

Insure that the setting for Router Mode is configured to read "Off (Bridge Mode)"

Once you have confirmed that the Time Capsule is configured correctly, everything else is the responsibility of the Motorola modem/router as far as network routing and IP address assignments for devices.

If you continue to have IP address issues, then you should contact the Internet Service Provider (ISP) that provided the Motorola device to you and ask them to fix the issue.

Reply

Answer 2

papaggaz Author

Level 1

8 points

Mar 23, 2015 9:06 PM in response to Bob Timmons

Thanks Bob, I went there as you directed and I had the Time Capsule set up that way already. Next time it happens I will reach out to cox. Thanks for the reply.

Reply

Answer 3

Mar 23, 2015 9:25 PM in response to papaggaz

If you have not performed a complete network power cycle in some time, now would be a very good time. This will give the Motorola device a fresh start and best opportunity to work correctly.

Power off every device on the network....in any order that you want

Wait a minute

Power up the Motorola and let it run for 5 minutes

Start up the next device and let it run a full minute

Keep starting up devices one at a time about a minute apart until the entire network is back up

Reply

Answer 4

papaggaz Author

Level 1

8 points

Mar 25, 2015 7:46 PM in response to Bob Timmons

Thanks Bob, I went there as you directed and I had the Time Capsule set up that way already. Next time it happens I will reach out to cox. Thanks for the reply.

Reply

Answer 5

papaggaz Author

Level 1

8 points

Mar 25, 2015 8:20 PM in response to Bob Timmons

The problem is happening again. My new macbook air cannot connect to the wireless networks in the house named 1) davara (from the Motorola SG6580) or 2) Apple network 1d76b7 (on the time capsule). I called Cox (my internet provider) and the tech immediately said I have the time capsule set up wrong and to call apple.

So here's my setup: the Motorola SG6580 is connected to the cable wire from the outside and has a wireless network available called "davara". I have an ethernet wire connected from the Motorola to the Time Capsule, I set up a "new" network on the Time Capsule called (the default) "Apple Network 1d76b7". I have the router mode off as you showed above. Two wireless networks are running. Can I have that without any IP conflict?

Heres the current DHCP snapshot from the Motorola where no IPs seem to be in conflict The current error message on the Macbook Air says " WI-FI does not have an IP address and cannot connect to the Internet" from the Network popup in System preferences

Where next?

Reply

Answer 6

Mar 25, 2015 9:02 PM in response to papaggaz

The AirPort Extreme is set up correctly. Any other type of setup will create an instant error message in AirPort Utility. You will see this if you try.

The MacBook Air, or any other device on the network receives its IP address from the Motorola modem/router. The AirPort Extreme is not involved in this process at all since it acts as a pass through device in Bridge Mode, which is the correct setting to work with another modem/router on the network.

The MacBook Air will not connect until it receives a valid IP address from the Motorola modem/router. Some ISPs limit the number of devices that will be able to connect to a network. Five to seven devices is common among ISPs that limit connecting devices.

Power off 3 or 4 of your other devices, wait a few minutes, restart the MacBook Air, then see if the MacBook Air can connect. If it can, you know that your ISP is limiting the number of devices that will be allowed to connect to the network that it is controlling. Ask the provider to configure the Motorola to allow more devices to connect.

If the MacBook Air still cannot connect, then you should contact Apple Support, or take the MacBook Air to an Apple Store to let them take a look.

Reply

Answer 7

Mar 25, 2015 9:27 PM in response to Bob Timmons

Wrote AirPort Extreme in the previous reply, but meant to say Time Capsule, although a Time Capsule is an AirPort Extreme with a built in hard drive, so router wise, they are the same product.

Two wireless networks are running. Can I have that without any IP conflict?

Yes, if the device that is allocating IP addresses is operating correctly. That would be the Motorola.

If you want the Time Capsule to allocate IP addresses for the entire network, then it is the Motorola device that must be reconfigured to operate as a simple modem in bridge mode. Then, the Time Capsule will be your network router with a simple configuration change.

I'm not recommending that you do this, since it is not easy, and your ISP will be less than thrilled to help you with this.

You will lose the wireless that the Motorola has been providing if you do this, and possibly some other services like phones, if you have them tied into the network as well.

Reply

Answer 8

Mar 25, 2015 10:12 PM in response to papaggaz

Just to add to Bob's comment .. when I look down the list of hosts you have so generously provided.. (makes life so much better).. I do not see the TC in the list.. as such the problem is the TC has dropped right off the network.

Can you please double check this list.. unless you have given the TC base station a very unusual name it is not listed.. and it has to be to work.

The TC latest AC version definitely has issues with the SB model cable modems.. not sure why but they are very problematic when together.

If you have bridged the TC and have it plugged into the router WAN TC to LAN SB6580, please move the cable to any of the LAN ports on the TC.. even test them one by one.. it works better to be off the WAN port.. if that also fails you might need to get the TC replaced.. or use a network switch between them.

If you post a screenshot of the setup of the TC from airport utility in one of the computers that would also be a big help for us.

Reply