Should I replace the Time Capsule now that we have two MacBooks?

Add an HD or SSD for the new MacBook to back up to and continue backing up the other to the TC

Simplest, fastest and most reliable solution for the new MacBook. SSD a waste of money since Time Machine does not back up at high speeds. HD more than enough for Time Machine backups.

Trash the TC and use a single large HD/SSD with volumes created for each MacBook to backup to

Possible, but you will have to leave both Macs physically connected to the HD. You won't be able to back up over Wi-Fi if that is your goal unless you connect the HD to the USB port on the Time Capsule. In other words, you would not be able to connect the HD to your AT&T gateway because Time Machine backups would not be supported with the gateway. Only a few very Wi-Fi routers would support this type of setup.

Trash the TC and have individual externals for each MacBook to back up to

Best solution in terms of simplicity, speed and reliability, but would require a wired connection from each Mac to each HD. it would not hurt to leave the TC working as well and back up to both the TC and the external hard drive connected to each Mac. In other words, a dual back up plan.

What I meant was connect an external drive to the Time Capsule via the USB port.

Thanks for the clarification on that.

As I said above.....You won't be able to back up over Wi-Fi if that is your goal unless you connect the HD to the USB port on the Time Capsule.

While I assumed.....(dangerous thing to do).....that you would be backing up both Macs over Wi-Fi this way......you could certainly back up the new Mac to the new drive connected to the USB port on the Time Capsule and continue to back up the other Mac to the Time Capsule's internal hard drive.

Downsides......the USB port on the Time Capsule is an old and slow USB 2.0 design. Backups are going to be slower going to a HD connected to the USB port on the Time Capsule than backups directly to the Time Capsule.

That USB port on the Time Capsule is underpowered, but it will work with most HDs that I've tried. Worst case, you might need a powered USB hub to connect to the Time Capsule's USB port.

I would not advise buying a HD that does not have its own built in or external power supply and must depend on the Time Capsule's USB port to supply operating power to the HD.

The HD connected to the USB port on the Time Capsule must be set up in Mac OS Extended (Journaled)

format. You probably won't be able to find an HD that is pre-formatted this way, so you'll have to use Disk Utility on your Mac to set up the hard drive.

At this point, you are probably thinking that this is going to be more complicated that you might have thought. That's understandable.

For what it's worth, I back up both Macs here directly to an attached HD for Time Machine backups. And, I also back up to my Time Capsule as well. So, I have a dual backup system. The Time Capsule is frankly overdue to fail, but I'll be covered when that happens.

Now, things get more complicated. What if the Time Capsule hard drive fails? You will lose the backups of the "other" Mac that is backing up to the Time Capsule. If that occurs, you could back up the "other" Mac to the HD connected to the Time Capsule's USB port.

But what happens if the power supply on the Time Capsule fails? Then, you are out of business for Wi-Fi backups with the HD connected to the Time Capsule's USB port.

So far, it looks like you want to back up using Time Machine using Wi-Fi. There are only 3 ways that you can accomplish this using the Time Capsule.

• Back up both Macs to the Time Capsule
• Back up one Mac to the Time Capsule and another Mac to a hard drive connected to the USB port on the Time Capsule
• Back up both Macs to a hard drive connected to the Time Capsule's USB port

My advice......the Time Capsule hard drive is the most likely component to fail, so adding a new hard drive to the USB port on the Time Capsule and backing up both Macs to that drive would make good sense. You could continue to also back up one or both Macs to the Time Capsule if you wish.

The big downside.....the age of the Time Capsule. If you are thinking about replacing the Time Capsule and you want to back up both Macs over Wi-Fi there are only 2 ways that you can do this.

• Highly recommended.....would be to purchase a Network Attached Storage device, or NAS as they are commonly known. It's similar to the Time Capsule except that it is not router....(which you don't need). Do some looking online for "NAS". The most often recommended NAS is Synology. It is also among the most expensive.

• Add a Synolog router to attach to the AT&T gateway. You don't really need the router portion of the Synology product (just as you don't need the router section of the Time Capsule), but you do need the USB port on the back of the Synology router. This is one of the very few routers to which you can connect a hard drive and back up using Time Machine to the drive over Wi-Fi.

By far the simplest, fastest and most reliable way to back up would be to connect a hard drive directly to each of your Macs. So, 2 hard drives would be required, one for each Mac. But......no backups over Wi-Fi in this type of setup.

Good plan.

It would not hurt to keep backing up your Mac to the Time Capsule and add the new Mac for backups to the Time Capsule as well.

Time Machine will automatically alternate backups between the Macs and hard drives, so you don't need to worry about backing up manually.