Do I need it in Modem mode?

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Hi all,

My current setup, VirginMedia hub 3 in Modem mode attached to my ASUS AC88U router, wired into that is my old ASUS AC68U router and a gigabit switch which in turn has another gigabit switch chained off of it.

it’s been working fine for years now but suddenly I get random DHCP errors from the virgin media hub, not ideal as, like lots of people, we are working from home although we always have done, multiple conversations with the idiots at virgin who even tried to sell us a new dongle that is “guaranteed to extend my wireless and wired connections!” They are sending an engineer tomorrow, they have told me the engineer won’t touch it if it’s in modem mode so I have turned it back to router mode although I still expect the, to blame anything else on my network and not the hub.

question is, do I even need it it modem mode? What’s the benefit of modem mode vs router mode when plugged in as a gateway to the AC88?
Also quick side question, should I get a single 8 port gigabit switch to replace my 2 4 port gigabit switches?

thanks I’m advance.
 
Having two routers leads to 'double NAT' which means traffic goes through multiple NAT translations and this can cause issues with voice/video calling and some MS 365 apps don't work well with it either. Your VM Hub should be in modem mode, AC88U working as the router and DHCP server and AC68U should be put into access point or bridge mode as well.
 
So you have Virgin super hub in route mode. With another 2 routers. And you wondering why it’s not working? What is your actual setup?
 
So VM are idiots because you chose to install and configure two additional routers and they can’t tell you what’s wrong with them anymore than we can tell you based on the lack of information posted? You have to see the irony here.

Firstly the SH3 shouldn’t be doing DHCP if it’s in modem mode… so how exactly have you configured each router? Which one is handling DHCP? How is the secondary configured? What specifically are the errors you are getting.
 
So I seem to have over complicated my initial post, my current setup is…

VM hub in modem Mode, plugged into my AC88U router, the AC86 router is setup as a mesh, so really I only have the 1 router, issue is VM have told me to put the Hub back into normal router mode for the engineer tomorrow because he won’t touch it if it’s in modem mode.

The DHCP error is what sometimes comes up when looking at the internet connection on the router once it’s dropped.
 
These DHCP errors, are they on the LAN or WAN side of the AC88U?

I'm not at all surprised that VM want the Hub putting back into router mode.

Whilst double NAT is far from ideal, it's worth putting the Hub back into router mode and seeing if the problem remains. If you have any port forwarding in place that without additional farting about that won't work at this point.
 
These DHCP errors, are they on the LAN or WAN side of the AC88U?

I'm not at all surprised that VM want the Hub putting back into router mode.

Whilst double NAT is far from ideal, it's worth putting the Hub back into router mode and seeing if the problem remains. If you have any port forwarding in place that without additional farting about that won't work at this point.

it’s the WAN side that comes up with DHCP error, the engineer has replaced the hub (says they should be replaced every couple of years and I’ve had this one for 10), I’ll try putting it back into modem mode later and fingers crossed.

Thanks for the reply.
 
it’s the WAN side that comes up with DHCP error, the engineer has replaced the hub (says they should be replaced every couple of years and I’ve had this one for 10), I’ll try putting it back into modem mode later and fingers crossed.

Thanks for the reply.

He’s either telling you what he thinks you want to hear - the SH3 was only launched in 2016 - or you have no idea what you have and just let him walk out with a SH2, which isn’t affected by any of the Intel Puma issues.

Again, what specifically is the error you keep referring to? Copy and paste the relevant log section from the router. Without you at least giving us basic relevant information then all you will get is conjecture.
 
In theory if the errors are on the WAN side then your messy internal setup shouldn't be the problem. How often does the DHCP error occur and how do you resolve it or does it resolve itself?
 
So I seem to have over complicated my initial post, my current setup is…

VM hub in modem Mode, plugged into my AC88U router, the AC86 router is setup as a mesh, so really I only have the 1 router, issue is VM have told me to put the Hub back into normal router mode for the engineer tomorrow because he won’t touch it if it’s in modem mode.

The DHCP error is what sometimes comes up when looking at the internet connection on the router once it’s dropped.


I have mine in modem mode, ie SH3 to router on ground floor then powerline adaptors, ie on mid landing to the top floor powerline adaptor and then 8 port network gigabit switch top floor to it , no issues for me this way. My wireless from router ground floor to top floor reaches fine but I prefer wired LAN in general for gaming etc so disabled the wireless part on my powerline adaptors and have it as a straight LAN pass through.


I only use my wireless laptop and wireless tablet on top floor via router, rest is all ethernet cable. Even then I could plug in the ethernet cable on my gigabit switch and use wired if I wanted to on my laptop.
 
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without any 'actual' error messages this thread is useless.

The DHCP error
what error?

is what sometimes
sometimes? when is sometimes?

comes up? What it pops out the top of your screen like a toaster? What exactly do you mean

when looking at the internet connection
what do you mean by this? what exactly are you looking at? the wires ? the lights ? the status page? windows network settings? some details would be ever o helpful

on the router once it’s dropped.

What's dropped? where? on the floor ? how do you know?
 
Thanks those with the proper replies, I have now remembered why I refrain from posting on these forums, too many self important “know it all” keyboard warriors who don’t post to help but post to mock, forum trolls!
 
Thanks those with the proper replies, I have now remembered why I refrain from posting on these forums, too many self important “know it all” keyboard warriors who don’t post to help but post to mock, forum trolls!
quality of the answers is indicative of the quality of the question tbh.
 
Thanks those with the proper replies, I have now remembered why I refrain from posting on these forums, too many self important “know it all” keyboard warriors who don’t post to help but post to mock, forum trolls!

quality of the answers is indicative of the quality of the question tbh.

I see no trolling - by those replying, at least. You can't ask a wishy-washy question, admit you provided confusing info, refuse to clarify or provide actual stats and logs, and then complain you've not had proper replies. Ironic to throw your toys out the pram, and accuse those trying to help you of trolling, when your own question was verging on Sealioning itself.

Sealioning
A subtle form of trolling involving "bad-faith" questions. You disingenuously frame your conversation as a sincere request to be enlightened, placing the burden of educating you entirely on the other party. If your bait is successful, the other party may engage, painstakingly laying out their logic and evidence in the false hope of helping someone learn. In fact you are attempting to harass or waste the time of the other party, and have no intention of truly entertaining their point of view. Instead, you react to each piece of information by misinterpreting it or requesting further clarification, ad nauseum. The name "sea-lioning" comes from a Wondermark comic strip.

To be fair, your post was very poorly written and formatted; But, you don't seem to be asking about the VM issue at all, and hence it (and the related log entries etc) is a red herring and irrelevant to the thread.

From what I gather, and correct me if I'm wrong:
  • You have DHCP errors showing in the log from the WAN side of your VM SuperHub 3 (which you were asked to provide but haven't).
  • Your connection (obviously) drops when the DHCP failure occurs.
  • You have a tech visit booked by the 'idiots' at VM.
This is background info, and doesn't form part of your question(s).
  • They've told you that they won't touch the SH if it's in modem mode.
So you're actually asking:

1) What's the point of modem mode anyway, and do you need it?
2) Do you need to switch back to router mode for the tech visit?
3) Is it worth replacing your 2x 4 port switches for 1x 8 (or larger) port switch?

Assuming I'm correct:

1) As someone above said, you don't want to end up double-NATing your home network (LAN). The SH should be in modem mode, if you're using your own router. Read up on double NAT if you're curious why. Again, avoid the Sealion.

2) No, I've never known a tech complain about modem mode. Ever. Leave it as it is. Last time I had a tech visit (last year), I had my SH4 in modem mode, an x86 OpenBSD box performing edge routing, NAT and firewalling, a Docker container handling DHCP and DNS, and a Ruckus enterprise WiFi AP (R710) performing wireless duties. The tech didn't even blink and sorted the issue in 10 mins flat.

3) No... and yes. You can have as many switches as you like so practically there's little difference between 2x 4 or 1x 8 port switches (or whatever). You're limiting all the devices hanging off them to sharing a single 1Gb connection on the LAN (due to their uplink to your other switch(es)), but that's hardly the end of the world on most home networks. You're also paying 2x the power bill, but 2x 50p a year isn't massive either way. Switches are very low power devices. But yes, it'd be tidier, easier, and save a few quid on leccy to consolidate into one larger switch if you wanted to. Your call.
 
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