Super Hub 3 slow in modem mode

[LPJA]

I have had my broadband upgraded to vivid 350 and the router to super hub 3, since then I have had poor speeds (something I am not used to with virgin).

If the SH3 is in router mode I am getting around 350mbps wired connection, as soon as I put it in modem mode and connect my Asus n66u the speeds drop to 120mbps.

Why???

I did not have any issues with my SH2 and this is the only thing that has changed.

I am getting quite frustrated with VM as when I spoke to there support team, they insinuated it was my home network and not there SH3.

I beg to differ! 

[Blueyonderer]

I contributed to this thread not long after it opened, having suffered from low download speeds in modem mode. I decided to give it another try after receiving a firmware update to my SH3 a couple of months ago. My network has been running at full speed since then, configured normally without any futher issues.

[oldbrad]

I notice that my SH3 connects to a different network segment in modem only mode than it does in router mode. 213,106,111.* modem only 82.17.139.* router. Why? Is this cause of speed differences?
I pay for 100Mbps. I see when wired: 75 in router, 100+ wifi, but only 35 and in 20 in modem mode.
VM comment please.

[oldbrad]

This is good, but I have a new SH3 which I assume has the latest firmware. Admin, Info says: Hardware version 10, Software version 9.1.116.608

[jungliztik]

I'm going through this same pain.  I was previously on the VIVID150 service and using my SH2AC in modem mode, sitting in front of a 10 Zig box running pfSense using the onboard NIC connected to VM and a USB NIC for the internal LAN.  This setup has been working perfectly for ~12-months with no issues.

Yesterday, I got my SH3 as part of an upgrade to the VIVID350 service.  Hardwired using CAT6 between the SH3 in router mode and my Thinkpad, I was getting ~385Mbps down / 21Mbps up.  Subsequently, I enabled Modem Mode and introduced my pfSense router into the infrastructure and like many other posters, my speed test results are significantly reduced (~180Mbps down / 21Mbps up).  I've done many, many tests and the subpar results are, unfortunately, consistent.

I'm going to try using different hardware for pfSense and so will be trying the Intel NUC currently hosting my FreePBX system to see if it makes any difference.  An annoying thing for me is that in the past month I sold my Linksys WRT1900AC as it was gathering dust and the pfSense option was working so well.

[legacy1]

Connect a PC up to modem mode and do a speed test like that (power off hub for 2mins to allow change over) if speed is good copy its MAC to your WAN pfSense NIC and connect that in place.

[oldbrad]

legact1

That's very interesting. Did you really mean "Connect a PC up to modem mode". If so how do you do that?

[ktakodra]

just plug in a windows pc to the modem it will work as long as you have dhcp enabled ,to browse to the  modem from pc use 192.168.1.100 or somthing like that.

The px should be able to access the internet too

when you replace the pc with your router you will need to reboot the virgin modem for it to provide a dhcp offer to your router 

[jungliztik]

Thanks for the suggestion. I turned the SH3 off for 5-mins and then started it in modem mode with my Thinkpad connected via CAT6. The laptop was configured to obtain an IP address via DHCP and sure enough, I had internet access and the speed test results were fantastic.
I then obtained the MAC address from the SH3 and proceeded to define it against the WAN interface on my pfSense host (spoofing). When I rebooted both boxes (SH3 and pfSense), the WAN interface showed as being connected on 0.0.0.0 (i.e. link was up), however, from another node on my network I couldn't even ping 8.8.8.8 (I got Destination Host Unreachable returned for each attempt)

[Roger_Gooner]

I have a router behind my hub in modem mode without needing to clone the hub's MAC address. It's not as if VM only allows you to have a single active internet connection at any time.

[legacy1]

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@jungliztik wrote:
Thanks for the suggestion. I turned the SH3 off for 5-mins and then started it in modem mode with my Thinkpad connected via CAT6. The laptop was configured to obtain an IP address via DHCP and sure enough, I had internet access and the speed test results were fantastic.
I then obtained the MAC address from the SH3 and proceeded to define it against the WAN interface on my pfSense host (spoofing). When I rebooted both boxes (SH3 and pfSense), the WAN interface showed as being connected on 0.0.0.0 (i.e. link was up), however, from another node on my network I couldn't even ping 8.8.8.8 (I got Destination Host Unreachable returned for each attempt)

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No copy your MAC of the laptop to your pfSense