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New Member

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67 Messages

Friday, February 12th, 2021 10:12 PM

BGW320-500 Bridge Mode and/or IP Passthrough Question

Hello everyone,

I have 1Gbps home fiber from AT&T.  I've had it for 2 years, works great.

Yesterday, a tech visited to upgrade my equipment to a brand new BGW320-500.  I also ordered a static IP address.

What I want to do is have this device be as "dumb" as possible.  I have a Ubiquiti Dream Machine Pro, and I want to configure this device with the static IP address I have, and, have it handle all routing/security/etc.  i.e. I want the AT&T device to do nothing (no wifi, no firewalls, nothing), and, I also do not want the AT&T device to give out its own IP addresses (I want my Ubiquiti Dream Machine pro) to handle everything (as if it was directly connected to the internet itself).

I've been told what I want/need is to configure the AT&T device to be in "Bridge Mode".  However, I cannot find this setting in the config menus.  I do find "IP Passthrough" which people have told me is essentially the same thing. Is that accurate?  Is "IP Passthrough" what I want?

If IP Passthrough is what I want, then how do I configure the AT&T device, with a static IP address?  Or no IP address?  

Any help & guidance would be appreciated.  I've searched the forums and cannot make clear sense on what I've found there.

Thank you,

Mark

ACE - Expert

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33.2K Messages

3 years ago

Do you have Public Subnet Mode on?  That's the way a tech would set you up, but isn't compatible with Cascaded Router.  Make a screenshot, just in case you want to put it back, then turn it off.

New Member

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67 Messages

3 years ago

As always, @JefferMC you are correct:  Public Subnet Mode was on.  I've now turned it off (after taking a screen shot).   Cascaded Router Enable options now work.  Thank you.

Question:  When I follow your instructions regarding IP allocation (Home Network -> IP Allocation), and when I click the Allocate button beside my router (UDMP or, my Linksys which I'm experimenting as a dry run before I engage my UDMP), an IP Allocation Entry data shows up (see screenshot below).  Do I need to do anything with this data?  Do I need to click SAVE?

Thank you,

Mark

New Member

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67 Messages

3 years ago

The list is Private Fixed:  192.168.1.64 to .253

New Member

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67 Messages

3 years ago

To clarify my question:  I presume that 192.168.1.67 is the Cascaded Router Address.  You are correct that the subnet mask is already correct.  However, what is 'network address'?  You mentioned that is my 'block address' but I dont know what my block address is.. Thank you

New Member

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67 Messages

3 years ago

is the block address the network base address?

New Member

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67 Messages

3 years ago

Apologies for all the questions and posts  @JefferMC , I do appreciate your assistance and attention.  

I found this thread on the AT&T forum that, I think, contradicts some of your instructions:  https://forums.att.com/conversations/att-internet-equipment/adding-a-cascading-router-to-existing-att-routermodem/5defd9efbad5f2f6068446e2

Here they say to turn on IP Passthrough first, then set up Cascade Router (vs, as I understand it:  turn off IP passthrough and only work on cascade router).  Should we do both (IP Passthrough -> Cascaded Router)?

Thank you again (no more posts from me, promise)

ACE - Expert

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33.2K Messages

3 years ago

Yes the Network address is the base address, as I said above:

The first address is the Network base address, which is evenly divisible by 8.  This is not usable, but is what you fill in for the "Network Address" when setting up your Cascaded router. 

ACE - Expert

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33.2K Messages

3 years ago

In my opinion, IP Passthrough SHOULD NOT BE POINTED to your Cascaded Router.  If you want to have an IP Passthrough'ed router, I would make it different from the router handling your Public Subnet.

New Member

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67 Messages

3 years ago

Well, this didn't work.  I attempted to go through the steps and it resulted in no access.  i couldn't even access the gateway.  I did a restore to factory settings manually, that brought it back up, but now I have no idea if the static ip settings are retained or lost all together.

Also, I tried going through the steps again:

-my linksys (stand in for my UDMP until I get this right) gets a DHCP address from gateway

-I turn on cascade and enter this ip address in the router address, I enter in the network base address, the subnet already filled in correctly 

==This returns an error "Another client as the SDB write lock" which I have no idea what this means.

So.... back to square 1 I guess

ACE - Expert

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33.2K Messages

3 years ago

Once you clear the Public Subnet Settings, save and restart the gateway.  Then try to set the Cascaded Router settings.  Save and Reboot.  

Once that's done, then configure your netgear with the public subnet on its LAN.

(edited)

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