Superhub Virgin Business Superhub now has Modem Mode - Page 13

pcfarrar · 24-07-2015, 21:43

Quote:

Originally Posted by Sephiroth

Next week we're installing VMB 50 meg and we need to be in modem mode.

Seeing how long this thread has been running, is modem mode reliable?

Are there any gotchas still lurking?

Thanks in advance.

Modem mode only works if your using a dynamic IP.

drsox · 24-07-2015, 21:53

In summary:
Modem only mode will only work if you have an IP range from VM rather than a single static IP.

Sephiroth · 24-07-2015, 22:28

Thanks for responses so far.

Sephiroth · 30-07-2015, 20:25

We got it installed at our client location and it all works 50/6.

Because we needed the static IP, we left the Business SH1 in router mode. We then went Ethernet-->Fibre converter-->Fibre patch panel-->Fibre-->Fibre converter-->Ethernet-->CPE. So that all worked as expected.

We're having trouble with our own L2TP tunnel but this is being handled by our experts - at least I hope they are.

Pity we couldn't use modem mode.

rhyds · 30-07-2015, 21:32

We had problems with our VPNs through the superhub. In the end we enabled the superhub's firewall (Set to low) and then enabled IPSec etc, and they started working.

Sephiroth · 31-07-2015, 16:33

The engineer who set this up for me (in my capacity of working for a large company) did indeed turn the firewall off. When I advised him to turn it on, instead he remotely put the SH into modem mode, acknowledging that the IP address would be dynamic now. Of course the VPN side worked.

My understanding is that the IP relationship between the SH and the CMTS is dynamic and it is the L2TP tunnel set up by the firmware that maintains the static IP address passed on to user functions. Is that so?

In that case, if the dynamic IP address changes, would the tunnel still be able to retain the static IP address and would remote management using the static IP thus still work?

ccarmock · 31-07-2015, 20:47

You are right - the fixed IP addresses are delivered via the L2TP tunnel, and are independent of the DHCP assigned address that the Superhub gets. I believe that IP address is similar to the original 'sticky' IP addresses the old 10 Mb/s business service had. An earlier version of the firmware used to show those- but since you're in Modem mode you'll be using that one. Try an nslookup of it - y9u might see if of the form xxxx.static.virginmediabusiness.co.uk

The L2Tp tunnel will ensure you get your fixed IP address (or addresses) even if the DHCP assigned address changes. It also means they survive a node split. Previously there was a chance you could get new addresses following a node split.

Sephiroth · 31-07-2015, 21:30

Thanks for that. To be absolutely sure of what you're saying, I'll put it as a question:

In modem mode, is the VMB Hub still putting through an L2TP tunnel and gaining the static IP address?

ccarmock · 01-08-2015, 00:13

As far as I understand it no in modem mode the L2TP tunnel does not get established. It would be worth checking what IP address you get in modem mode and checking what format the reverse DNS entry is - that will be a clue as to what pool of addresses you have in that mode,

qasdfdsaq · 04-08-2015, 01:25

The whole reason static IP is not available in modem mode is because there is no L2TP tunnel.

Sephiroth · 06-08-2015, 07:56

Just to explain why I need advice from the forum - the VMB line that our organisation is using has been commissioned through a 3rd party ISP who have responsibility to us for maintaining the service. Thus, although I was present at the install, I don't have the SH password.

I advised them to set firewall LOW and enable the VPN settings. Instead, they put the SH into modem mode, plugged it into their own RouterBoard that establishes its own L2TP tunnel through to their ISP infrastructure and onto the Internet.

It works but I'm awaiting from them confirmation as to whether or not they can now gain remote access to the SH. So another question to play on your kindness again:

In ROUTER Mode, if they were accessing the SH remotely (which they did), which IP address would they be using? The static on or the DHCP given one?

I expect to hear from them shortly as to what is going on, but they might be playing cards close to chest unless they can actually get into the SH using the DHCP allocated IP address that they may have discovered through data packet analysis.

Thanks in advance.

Kushan · 06-08-2015, 10:05

As far as I understand it (and I could be completely wrong, especially when it comes to the business side of things), the Superhub will always respond to a request on 192.168.100.1, regardless if it's in modem or router mode. Even though in router mode, 192.168.100.1 isn't on the subnet, it will always respond.

Sephiroth · 06-08-2015, 10:12

Quote:

Originally Posted by Kushan

As far as I understand it (and I could be completely wrong, especially when it comes to the business side of things), the Superhub will always respond to a request on 192.168.100.1, regardless if it's in modem or router mode. Even though in router mode, 192.168.100.1 isn't on the subnet, it will always respond.

Yeah - but if they're signing into the BSH remotely, they need to know the externally granted IP address.

Ignitionnet · 06-08-2015, 11:27

They can't log into the SH if it's in modem mode unless they can bounce off a device on the LAN and then access 192.168.100.1 via HTTP.

APS · 06-08-2015, 11:29

Quote:

Originally Posted by Sephiroth

Yeah - but if they're signing into the BSH remotely, they need to know the externally granted IP address.

Probably not if their router is automatically setting up a tunnel into their own network as the modem will then be accessible via the tunnel as a local device.

One frustration for those of us who need the fixed IPs is that VM have not released and do not support/allow us to set the SH in modem mode and let our own routers negotiate the L2TP tunnel to their server, thus taking the flakely firmware out of the equation!