Having an issue trying to set up my Airport Extreme (A1521)

If you purchased an A1521 AirPort Extreme thinking that it included a built in hard drive that could be used for Time Machine backups, you have unfortunately purchased the wrong product.

You need an A1470 AirPort Time Capsule for that purpose.

Or, are you saying....(but did not mention in your post).....that you have a USB drive connected to the AirPort Extreme that you plan to use for Time Machine backups?

Please clarify, so we will have a clear understanding of what device that you have.

That USB drive will need to be formatted in Mac OS Extended (Journaled) in order to be used for Time Machine backups.

Unfortunately, the port on the AirPort Extreme is old and slow USB 2.0, and the internal processor further limits speeds to about half that of a normal slow USB 2.0 port on the computer, so your backups are going to take place very slowly.

But, before you work on the USB drive, it is much more important to first make sure that the AirPort Extreme has been configured correctly. There will be a solid green light on the Extreme when this occurs.

Please detail how the AirPort Extreme will connect to your network.

Will it connect to your existing modem or router using a permanent, wired Ethernet cable connection?

Will the AirPort Extreme be configured to provide a wireless network, or are you going to try to use the wireless network that your existing router might already be providing?

What is the make and model number of your modem or modem/router?

The Airport Extreme cannot connect to your Frontier router using only a wireless connection. It must connect using a permanent, wired Ethernet cable connection if you want the AirPort Extreme wireless to have Internet access.

It is possible to set up the AirPort Extreme to provide a wireless signal that will not be able to connect to the Internet, but, in order to back up, you will have to manually log off of the Frontier network and then log onto the Airport Extreme network to back up....then, log back onto the Frontier network when you want to have Internet access again.

My recommendation would be to set up the AirPort Extreme with Internet access and then use the AirPort Extreme wireless network to back up to the USB drive at the AIrPort Extreme. Backups will at least occur faster this way, because the AirPort Extreme will have faster wireless than the Frontier. You could use the Frontier wireless for guests, or the kids, or if you don't need another wireless network, there is likely a way to turn off the WiFi function of the Frontier router.

Another advantage to using the AirPort wireless is that backups will occur automatically, and you won't have to manually switch networks to back up and then switch back to another network for Internet access.

Frankly speaking, if your goal is more efficient Time Machine backups, an AirPort Time Capsule would be able to back up 2-3 times faster than the AirPort Extreme with an attached USB drive.

An even better option would be to simply connect the USB drive directly to your Mac and back up that way. Backups will be more reliable this way and faster as well.

But, it's your call.

Help for the amber light > https://support.apple.com/en-us/HT203198

More help here > AirPort Utility: Set up a new base station