VPN client no access, two ip addresses

Unanswered Question
Jan 30th, 2008


Vista and VPN client v5.0 with 3000 concentrator. After logging in an ipconfig shows Ipv4/subnet mask twice, giving two different IP addresses in the same pool and subnet. The gateway is blank, thus no access to LAN or Internet.

No unusual changes since problem started happening a week ago, flushed DNS cache, any ideas out there? Much thanks!

I have this problem too.
0 votes
  • 1
  • 2
  • 3
  • 4
  • 5
Overall Rating: 4.5 (2 ratings)
husycisco Wed, 01/30/2008 - 16:21

Hi Terence

So you loose local Lan and internet connectivity when you are connected to VPN

"giving two different IP addresses in the same pool and subnet." When you run ipconfig, it should list the interface name. If you see an ip under "Cisco Systems VPN Adapter" which is in same subnet with your local area network, that means VPN pool conflicts with your local subnet and with your local gateway.

Blank gateway is a normal output for Cisco Systems VPN adapter. Are you the 3000 concentrator admin?


terencekam Wed, 01/30/2008 - 16:31

Hi husycisco,

Thank you for your response.

The user's home network is most likely a different subnet from the pool VPN uses. Here's a bit more info:


This is what his ipconfig shows. Everything worked fine before. I'll have him reinstall the client to see if it helps. I will also see the log showing what IP the admin page shows he has when he sees two IPv4s. I do have admin rights to the 3000, if that's what you're asking.

Thank you,

husycisco Wed, 01/30/2008 - 16:49

According to the ipconfig you show, this is not a VPN client issue.

TCP/IP configuration of Local are connection of this PC is configured manually, and there is no gateway specified. And a secondary IP is assigned. You can do this by clicking advanced in TCP/IP properties and click add in IP addresses section above.

If a DHCP is configured at user's home, I suggest setting local area connection to obtain IP address automatically. If there is no DHCP, then he/she should enter gateway address manually as he/she did for IP address.


terencekam Thu, 01/31/2008 - 10:44

Thank you for your response.

If I did "ipconfig /all" it would show that the "Local Area Connection 2:" is Cisco Systems VPN Adapter.

Before connecting to VPN, the TCP/IPv4 properties of the VPN adapter showed as the IP. After connecting, the same window showed the first IP address of two in the same subnet. The DNS and DHCP IPs are correct.

DHCP is configured at user's home. The log in admin page of the VPN showed it issued the first of the two IPs, no record of the second one. Correction: he gets internet but not LAN. Pings to LAN resources map to the correct IP...

Again, if all else fails, I'll try to get him to reinstall the client but if any of this info rings a bell with you, please advise. Thank you!

husycisco Mon, 02/04/2008 - 10:32

I assume client gets internet via VPN endpoint. That means if he visits www.whatismyip.com while he is disconnected and visits again this site while he is connected, he should see two different public IPs. It may be a split tunneling issue.

It would be useful If you post your config.

Are there any other VPN clients connect to VPN endpoint and loose LAN connectivity?

terencekam Mon, 02/04/2008 - 10:37

We might not be able to figure the exact problem, because a reinstallation of the VPN client fixed the issue. Still, I was trying to figure out why it happened in the first place. In his network connections window there were two virtual LAN adapters for the virtual machines he was running, wireless, the LAN1 and LAN2 (cisco). After talking with more people some have this losing LAN connectivity issue rarely, usually it's not being able to connect the first time around.

The weirdest part was being able to access a share but not being able to ping it.

husycisco, thanks for your help, if it happens again I'll try the suggestion above.

husycisco Mon, 02/04/2008 - 10:54

"virtual machines he was running"

ah... virtual machine adapters and vpn adapters... always cause trouble when they are together.

Keep in mind that using the following tool to reset winsock and tcp paramteres fixes such kinds of issues for me usually


Nice to hear that problem is resolved and thanks for voting



This Discussion