100M : No WAN IP

[mecster09]

Hi,

New here but seeing as I'm struggling with a resolution on the Virgin community forums I hope I may get better luck here! My issue is covered in this post https://community.virginmedia.com/t5...3029350#M54002 however to summarise:

• In router mode I get an internet connection however after 10 minutes and mulitple T4 timeouts connection drops, this repeats constantly
• In modem mode with laptop connection or router I rarely get a WAN IP from the modem yet modem shows as online from Virgins end.

To expand on the last issue, I have tried connecting the laptop directly or using the router and running continuous pings to 192.168.100.1 (modem) and 8.8.8.8 (google dns). On power up the modem assigns a temp IP of 192.168.100.10 to laptop or router then tries to connect, 99% of the time the LAN IP ping to the modem drops and no WAN IP is assigned. 1% of the time a WAN IP is assigned and LAN IP ping continues no problem.

We have tried up to 8 different modems from Virgin (Superhub 2 and Superhub 2ac), 4 engineer visits so power levels and cabling is fine.
It feels to me there is an issue with Virgin DHCP assigning a WAN IP to any device connected to the modem unless it's the modem in router mode itself though Virgin support and engineers are still unsure.

Any thoughts or suggestions?

Thanks in advance.

[Kushan]

Originally Posted by mecster09

Hi,

New here but seeing as I'm struggling with a resolution on the Virgin community forums I hope I may get better luck here! My issue is covered in this post https://community.virginmedia.com/t5...3029350#M54002 however to summarise:

• In router mode I get an internet connection however after 10 minutes and mulitple T4 timeouts connection drops, this repeats constantly
• In modem mode with laptop connection or router I rarely get a WAN IP from the modem yet modem shows as online from Virgins end.

To expand on the last issue, I have tried connecting the laptop directly or using the router and running continuous pings to 192.168.100.1 (modem) and 8.8.8.8 (google dns). On power up the modem assigns a temp IP of 192.168.100.10 to laptop or router then tries to connect, 99% of the time the LAN IP ping to the modem drops and no WAN IP is assigned. 1% of the time a WAN IP is assigned and LAN IP ping continues no problem.

We have tried up to 8 different modems from Virgin (Superhub 2 and Superhub 2ac), 4 engineer visits so power levels and cabling is fine.
It feels to me there is an issue with Virgin DHCP assigning a WAN IP to any device connected to the modem unless it's the modem in router mode itself though Virgin support and engineers are still unsure.

Any thoughts or suggestions?

Thanks in advance.

First, log into your modem and post your modem stats - just to be sure.

Now, you're onto something with the DHCP side of things but it's not likely to be something with their DHCP server or you'd see more customers affected. However, I know that there is a limit to how many DHCP leases a single modem can acquire and it does it in such a way that if you swap around devices too much and too frequently, it'll just stop allocating new leases completely. Sound Familiar? Good, because there's a way to fix it. The below might seem bizarre and pointless, but trust me on this one.

Also, this is very important: Never ever ever unplug and plug in a different device when the hub is in modem mode without turning the hub off completely first. Let me repeat that: Turn the hub off, THEN plug your device in. If you try to "hot swap" while it's in modem mode, it'll refuse point blank to give you an outside IP address. Okay? Always turn the hub off BEFORE plugging anything into it. Don't just swap the devices and power cycle, this will cause issues even if it works sometimes.

Now finally, here's what you need to do. Again, follow these steps exactly.

Step 1) Put the hub into modem mode
Step 2) Power off the hub
Step 3) Plug the device you want to act as a router into the hub.
Step 4) Unscrew the Coaxial cable from your hub.
Step 5) Power on the Hub

Step 6) Wait exactly 10 minutes, not one second less. 10minutes. 600 Seconds. Go make a cup of tea, nip to the shops, do whatever takes at least 10 minutes. Do it.

Step 7) Screw the coax cable back in. Note that I did NOT say to unpower the hub, you leave that bad boy switched on.
Step 8) Wait 5 minutes. Again, 5 minutes, not 4, not 8, not a couple - 5 exactly. 5 minutes.

By now, the hub should be online. The usual lights will be on and it will be stable.

Step 9) Power off your router.
Step 10) Power off your hub.
Step 11) Power on your hub.
Step 12) Wait 30 seconds. Not 20, not 40...you get the idea. 30 seconds.
Step 13) Power on your router.
Step 14) Enjoy internets

Do that. Do exactly that.

[General Maximus]

Follow Kosh's wise words, they have solved many an issue such as this in the past. Just to clear up a few bits for you though because you are getting confused; modems do not assign ip addresses, routers and dhcp servers do. If your shub was in router mode then you would get a 192.... address but not in modem mode. If your laptop was directly connected to the shub in modem mode it would either get a wan ip from VM or it won't. So that would look like 82....... or 169.254......(which is what Windows assigns itself when it can't get a proper address).
If the shub is in modem mode and you are using a 3rd party router and connecting your devices to the router then you would expect the router to have the VM wan ip (which you would be able to see in the gui) and any attached devices to have a local ip issued by the router like 192.168......

If you haven't got yourself confused and knew all that then the problem you might have had, and would partially explain your connectivity issues, is if you are swapping cables and configurations around without rebooting anything like Kosh has intimated then things aren't going to work properly. You have probably had your laptop connected to your 3rd party router and let it get a local address, realised internet wasn't working, put the shub in modem mode and then connected the laptop to the shub. If that is the case then the laptop hasn't got a new ip address. The shub would need to be rebooted anyway and you would need to do an ipconfig /release /renew on the laptop to get it to look for a new ip address.

Come back and let us know if it works.

[Kushan]

Originally Posted by General Maximus

Follow Kosh's wise words

[General Maximus]

may he rest in peace

[mecster09]

Originally Posted by General Maximus

Follow Kosh's wise words, they have solved many an issue such as this in the past. Just to clear up a few bits for you though because you are getting confused; modems do not assign ip addresses, routers and dhcp servers do. If your shub was in router mode then you would get a 192.... address but not in modem mode. If your laptop was directly connected to the shub in modem mode it would either get a wan ip from VM or it won't. So that would look like 82....... or 169.254......(which is what Windows assigns itself when it can't get a proper address).
If the shub is in modem mode and you are using a 3rd party router and connecting your devices to the router then you would expect the router to have the VM wan ip (which you would be able to see in the gui) and any attached devices to have a local ip issued by the router like 192.168......

If you haven't got yourself confused and knew all that then the problem you might have had, and would partially explain your connectivity issues, is if you are swapping cables and configurations around without rebooting anything like Kosh has intimated then things aren't going to work properly. You have probably had your laptop connected to your 3rd party router and let it get a local address, realised internet wasn't working, put the shub in modem mode and then connected the laptop to the shub. If that is the case then the laptop hasn't got a new ip address. The shub would need to be rebooted anyway and you would need to do an ipconfig /release /renew on the laptop to get it to look for a new ip address.

Come back and let us know if it works.

Just to clarify, my router has a fixed IP address of 192.168.0.1 and during the boot sequence of the modem it gets assigned a temporary WAN IP of 192.168.100.10 (confirmed by Virgin and happens to all during boot sequence). Usually once the modem is post boot my router should be able to obtain a WAN IP 213.x.x.x etc however 9 times out of 10 this fails to happen.

I will attempt what was mentioned before this post after the engineer leaves tonight (4th visit).

I'm still confused why router mode disconnects constantly though less of an issue now I bought my own router.

[General Maximus]

if he swaps the shub again and it still doesn't work ask him to check the connections coming into your house to make sure they are clean and tight and not causing sporadic disconnections. If that doesn't help and he has ruled out anything in your house/customer premises being the issue, then ask him what the next step is what he is going to do to investigate it.

[Sephiroth]

From mecster's thread on the VM forum the following info to peops here might be helpful:

1/
Mecstsr's stats when posted always show good.

2/
The Network Log, when posted, always shows serious errors on the downstream which seems to us to be at the DOCSIS layer (which would prevent DHCP from functioning).

3/
First line support can't handle this kind of problem (and should not be consulted).

4/
The area PT is also likely not to understand the significance of the errors disclosed in your Network Log. But he will be able to detect if there is an issue with your coax from cabinet to home.

5/
Mecster has traction from one of the most respected Forum Team members who appears still not to have engaged Networks to examine your problem. If a need repull is needed, Networks won't be engaged until that has been done and the problem persists.

6/
There has been suggestion of an "earth fault". Normally a coax impairment would result in struggling power levels and poor SNR (RxMER). But if the earth fault is confirmed, then the PT would organise a repull.

7/
There is some mumbo jumbo coming from another regular poster in mecster's VM thread going on about ARP packets and broadcast flags. One of the Superusers is dealing comprehensively with that.

Make of the above what you will. Mecster is looking for second opinions and I hope the above synopsis assists the formulation of any opinions.

[General Maximus]

Originally Posted by Sephiroth

From mecster's thread on the VM forum the following info to peops here might be helpful

thanks, I didn't bother reading that to start off with, normally they are just duplicates and I hate reading stuff twice. Nice to see things are moving forwards and getting sorted though. It is an interesting read, I love seeing geeks arguing about stuff

[Sephiroth]

One of them is a geek (and not a very good one imo), the other knows what he's talking about, mon General.

[mecster09]

Unfortunately I've just attempted what was suggested above and still not working. Modem is still currently unreachable via Ping and no Internet. I've tested with both modem to router and modem direct to laptop, same outcome

[mecster09]

For those that are interested I've updated my Virgin post with Wireshark output and Network logs during the tests. http://community.virginmedia.com/t5/...3027946/page/9