Time Capsule Basic Question

Should I also assume that under the "Network" tab it should be set at "Off (Bridge Mode)" ?

That is correct.. although there is alternatives to that.

I happen to use Asus main router and have 3 or 4 airports in the rest of the network.. most are bridged but I use a couple of them in DHCP mode..

See No DNS error, Airport roaming network

I find bridge less reliable.. and for apple clients using the Apple router in dhcp mode with static IP simply works better.

In your situation I would recommend you do use bridge with simplest setup. If you run into issues of the computer losing the TC which seems to be common on sierra or high sierra.. try setting the TC to a static IP. Just go into the Internet tab.. and set whatever IP it currently has by dhpc. Plus if possible set the IP via DHCP reservations in the main router.. note carefully the static IP of each one.. that helps when Time Machine for example goes bonkers and cannot find the TC disk.. you can force the connection via the IP address.

If you still have issues.. then use the DHCP method on TC1 and plug TC2 into TC1 instead of the main router.. but you can also use DHCP on both of them.. but that is starting to get a bit too complicated.

I will run the Wireless Diagnostics app and see where I come out. I know on the Ubee console under "Wireless" you can scan AP's around you that will show who is using what channel on which Mhz. I think this is the same results you're after when you use the utility that MacOS offers.

Yes.. the tool you use doesn't matter.. it is the end result you want.

Apple scan

Asus router has the same thing. But the details particularly of RSSI, noise level etc are much more detailed in the Apple tool. The Asus is more sensitive and picks up lower level signals.

I'm sure there's a long lost tutorial somewhere in the archives that explains best practices.

The latest tutorial on roaming networks is well out of date.. it is amazing how Apple seem to ignore some aspects of networking and concentrate on others. We are constantly trying to help people understand correct setup of roaming.. if I point you to the document it is near useless.

Wi-Fi base stations: Setting up and configuring a roaming network (802.11 a/b/g/n) - Apple Support

It was updated in 2016 yet doesn't include AC wireless.. and what is woeful is it uses 5.6 version airport utility which Apple stopped supporting in Lion. The principles are still the same.. but details of how to configure it via v6 airport utility are entirely different.

So, you're suggesting I basically force my Ubee router/modem with a static IP as well as the Time Capsules?

I need to perhaps explain in greater detail or get more details from you.

Any standard domestic Internet service has a dynamic IP.. that is WAN side.. but the Router on the LAN side is static already.. eg your ubee modem router is perhaps 192.168.1.1 .. look it up or do a check on the airport utility by clicking on the world symbol.

My main gateway router has a static address of 192.168.2.254 (by default it would be 192.168.1.1 but I use that range for other things).

Each device on the network gets an IP from the main router.

For example.. my Time Capsule gen4. It is 192.168.2.153 and is dynamically assigned from the main router.

That means tomorrow it might be on another IP address. This makes things difficult.

So to fix the problem i can do two different things. singly or together.

I can edit the IP of the TC. Click edit .. click internet tab.

IT is currently set to DHCP

So I can change it to static IP. I just click static. All the current values swap to fixed values. Instead of greyed out because they are not controlled.

I can also go into my main router.. Asus.. in my case so it will look different to yours.

You can manually type in the MAC address.. but most routers wll now allow you to select from their list of DHCP clients. tcgen4 is there.

The IP address is the current one.. and name is same.. then you just click add.

It is now permanent.. that whenever this device with MAC address as below requests an IP it will always get 192.168.2.153

Keeping IP addresses permanent on the fixed network devices helps no end to keep them on the network.. or easily determine if it has gone missing.

Ping it.

So from computer I can open terminal and just type ping followed by the address or the name.

ping 192.168.2.153

PING 192.168.2.153 (192.168.2.153): 56 data bytes

64 bytes from 192.168.2.153: icmp_seq=0 ttl=255 time=3.823 ms

64 bytes from 192.168.2.153: icmp_seq=1 ttl=255 time=2.398 ms

64 bytes from 192.168.2.153: icmp_seq=2 ttl=255 time=1.763 ms

64 bytes from 192.168.2.153: icmp_seq=3 ttl=255 time=1.163 ms

^C

--- 192.168.2.153 ping statistics ---

4 packets transmitted, 4 packets received, 0.0% packet loss

round-trip min/avg/max/stddev = 1.163/2.287/3.823/0.989 ms

You can also ping by name.. but usually have to include the domain.

So

ping tcgen4

ping: cannot resolve tcgen4: Unknown host

So that fails.. but ping with the domain.. set correctly in the Asus.

$ ping tcgen4.local

PING tcgen4.local (192.168.2.153): 56 data bytes

64 bytes from 192.168.2.153: icmp_seq=0 ttl=255 time=1.410 ms

64 bytes from 192.168.2.153: icmp_seq=1 ttl=255 time=2.679 ms

64 bytes from 192.168.2.153: icmp_seq=2 ttl=255 time=2.589 ms

^C

--- tcgen4.local ping statistics ---

3 packets transmitted, 3 packets received, 0.0% packet loss

round-trip min/avg/max/stddev = 1.410/2.226/2.679/0.578 ms

I'm confused about the differences between roaming and extended networks.

A roaming network means all wireless routers are set to the same wireless name and security setting.. but are all independent and connected back to main router with ethernet.

Extended networks use wireless to extend wireless.. This immediately halves the speed. So extended wireless is NOT recommended where you can avoid it.

Both TCs have the latest software, are connected via ethernet cable to the modem/router and I am running MacOS Sierra 10.12.6 on the MacBook Pro that I access all three appliances.

Both TC should be set to create a wireless network.. it is up to you if you use the same or a different wireless name on all the units.. for roaming all must be identical name, identical security password and all should be set to WPA2 personal.

Beyond that you space things as well as you can so each Wireless Access Point (WAP) does not overlap too much with the others. You can also check that channels are selected correctly using a wireless analyser like one built into Mac OS since Mountain Lion.

Just post the screenshots.. we can figure it out pretty well from there.

RSSI min should be around -60db.. to get consistent speed..

For getting the fastest connection.. you really want less than -50db.. remember it is log scale so every 3db represents a doubling of power.

Conversely for noise you want levels at least 15db below signal.. but that is sometimes difficult. Wireless is designed to cope with noise but will cause speed degradation.