Really newbie question, when my AT&T router is unplugged, whole home network goes down

sed8em

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I unplugged my AT&T FIOS router this morning to do some cleaning and rearranging. When it was unplugged, my entire home network went down. I couldn't access my Wifi from my laptop and I couldn't access my various Raspberry Pi devices running stuff like my 3D printers.

My WiFi access point is a Ubiquiti AP LR. I would assume that even without internet, I should still be able to locally access clients on my home network, no?

How do I go about setting up my home network so even without internet, everything else like 3D printers/raspberry Pi/HP laser printer all still work?
 

auntjemima

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I unplugged my AT&T FIOS router this morning to do some cleaning and rearranging. When it was unplugged, my entire home network went down. I couldn't access my Wifi from my laptop and I couldn't access my various Raspberry Pi devices running stuff like my 3D printers.

My WiFi access point is a Ubiquiti AP LR. I would assume that even without internet, I should still be able to locally access clients on my home network, no?

How do I go about setting up my home network so even without internet, everything else like 3D printers/raspberry Pi/HP laser printer all still work?
Is the access point handling the DHCP? I would take a peek.
 

sed8em

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Ah, thats probably it.
I have a new managed switch coming this week that should be able to handle DHCP.

I only want the AT&T gear bringing internet into the house, nothing else.

I'm very new to advanced home networking and I'm learning as I go this week.
 

pendragon1

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Ah, thats probably it.
I have a new managed switch coming this week that should be able to handle DHCP.

I only want the AT&T gear bringing internet into the house, nothing else.

I'm very new to advanced home networking and I'm learning as I go this week.
wait for that then.
 

Nicklebon

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In the default configuration with AT&T fiber the ATT box (RG/residential gateway) is the router. It handles wireless, dhcp and everything else. You can setup what they call passthrough mode to use your own router but even then the RG can interfere with some things if you are a "power user." Many such users will bypass the RG all together but that is another subject completely unsupported by AT&T and becoming impossible in some areas.
 

sed8em

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Would it be better to set up a second LAN using the managed switch?
The AT&T router provides 192.168.0.1 -> 192.168.0.255.

Should I use the switch to provide 192.168.1.1 -> 192.168.1.255, for all the devices in my house?

And connect the router to the switch to provide internet services only to the house?
 

Nicklebon

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Would it be better to set up a second LAN using the managed switch?
The AT&T router provides 192.168.0.1 -> 192.168.0.255.

Should I use the switch to provide 192.168.1.1 -> 192.168.1.255, for all the devices in my house?

And connect the router to the switch to provide internet services only to the house?
Unless your talking about a layer 3 switch then a switch is not going to provide DHCP or any other layer 3 services ie routing to anything. A typical switch will just provide more ports. I assume atm you have everything plugged into your ATT RG. When you shut that down all your cabled devices went down with it. The same would happen if you shutdown a switch. A switch would allow you to power down the RG but not lose connection internally so long as the switch still had power. While the RG was down nothing coming up would get a lease or be able to renew a lease. That said dhcp clients typically renew at half the lease time so the DHCP server being down was not your problem. That is a giant red herring. I don't use consumer grade gear but with a real AP your wifi devices should have been able to communicate with other wifi devices on that same AP during this outage but obviously not with the internet or wired devices.
 

Vengance_01

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Ah, thats probably it.
I have a new managed switch coming this week that should be able to handle DHCP.

I only want the AT&T gear bringing internet into the house, nothing else.

I'm very new to advanced home networking and I'm learning as I go this week.
You are going to need a separate router. If you have fiber you should have an ONT. If that's running Ethernet, you should be Golden. If it's running coax then there might be some issues. Most switches only do layer 2 and don't handle routing
 

auntjemima

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I didn't know people used the stock modem for their connections. Weird. Been doing Modem > Router > Switch since I can remember.
 

auntjemima

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Most people do not know better, nor need another router, they just use the one their ISP provides them, remember, us here on [H] are a very very small minority.

Make senses. I feel you.

I just never want my connections accessible like that.
 
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bigstusexy

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You should be able to connect to other things, even if the AT&T router is doing DHCP, as long as the clients didn't lose connection. Wireless is the same but it's so easy for those devices to drop and reconnect.

So If your AT&T box is connected to a switch and everything else is on that switch, not connected directly to the AT&T box, then yeah it should still function. If they lost connection, if they require DNS and have no cache, then no, unless you know the IP directly.

I've not done anything with Ubiquity but perhaps they can do DHCP? You only want one device doing it in your network.

There is no need for separate networks. Just turn off the DHCP on the AT&T box and set something else with the same settings (I just looked, it's under Home Network > Subnets & DHCP)

You can check out the ISP Forums at dslreports.com, They've talked about true bridge mode and true substituting devices but I believe that was for VDSL U-Verse, not fiber. (AT&T FIber has been marked under U-Verse, but now is just AT&T Fiber. FIOS is Verizon) I'd be surprised if they aren't still using authentication on the WAN side and I haven't looked for transceivers that are parallel on the fiber, the enterprise stuff is all serial requiring to fibers per connection. (that I've seen, used)
 

Nicklebon

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You are going to need a separate router. If you have fiber you should have an ONT. If that's running Ethernet, you should be Golden. If it's running coax then there might be some issues. Most switches only do layer 2 and don't handle routing
With new installs of ATT Fiber the ONT and RG are a single box. Even when you have an older install you still have to use the ATT RG because they use 802.1x certs on RG to authenticate the router. There is plenty of talk about this over dslreports. Given the context of this thread the OP just need to plug a switch into the RG and his LAN/WIFI gear into the switch.
 

sed8em

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Think I got it figured out with a little bit of Google'ing.

I need to set the AT&T box into "IP Passthrough" mode, it uses subnet 192.168.1.0/24. Then set the UniFi controller up as the DHCP server, subnet 192.168.2.0/24 so there aren't any conflicts.

Does this sound right?
 

Nicklebon

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No. Your AP is not a router. It is just an AP. Get a switch. Plug switch and only switch into the AT&T RG. Plug all your gear into switch. If ubiquiti AP will cover what you need it to then you should disable the RG wifi. To use IP passthrough you would need to buy another router and plug that into the RG and the switch into the new router .... Needless complication for you.
 
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sed8em

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No. Your AP is not a router. It is just an AP. Get a switch. Plug switch and only switch into the AT&T RG. Plug all your gear into switch. If ubiquiti AP will cover what you need it to then you should disable the RG wifi. To use IP passthrough you would need to buy another router and plug that into the RG and the switch into the new router .... Needless complication for you.
The AP won’t be running the DHCP, the Ubiquiti controller box that is running the Unifi software would be
 

sed8em

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Can you make us a diagram of how your devices are physically connected?
Right now its just: AT&G fiber optic RG -> cheap Netgear switch from Best Buy -> Unifi AP LR and other hardwire ports to stuff like Xbox/desktop PCs.
UAP-LR is WiFi to tablets/phones/Ring doorbell/3D printer Octoprint RPi/etc.
 

Nicklebon

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The AP won’t be running the DHCP, the Ubiquiti controller box that is running the Unifi software would be
Buys you nothing and provides more potential for future problems. Leave the DHCP on the RG. Stop trying to overtech the plumbing for no reason.

To be clear there is a lot of talk about DHCP being down causing the issue. Most home device issue a dhcp lease for 86400 seconds ie 24 hours. Most clients will attempt to renew that lease starting at half the lease time, usually 12 hours. So unless your your RG was down for more than 12 hours DHCP had zero to with your connectivity problems. More likely the ubiquity AP took a dump because the lan interface was down. A switch would solve that problem assuming you don't power it off also.
 
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cdoublejj

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i have switch an AP and router. if the router goes down it all goes down. it's all dumb and has to make calls to the router. though thinking about it you'd think the switch could still handel local traffic. yuo know i haven't tried any connections while rebooting the router.

to be fair i have my own router and an ISP modem. i usually only reboot the modem.
 
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