wschwader-ga:
Thank you for the opportunity to help you overcome the connectivity
problems with the new computer. Of course, since you ultimately found
the cause of the problem yourself, it is a bit awkward to provide this
Answer! It will help in documenting some of the useful techniques that
can be used to debug connectivity problems in the future, though, so
should be of value to you.
The conflict between your LAN IP address space (10.0.0.x) and the IP
address that your NetScreen client is set up for (10.0.0.x) was indeed
the culprit here. The NetScreen client provides a VPN interface to
Windows, allowing Windows to automatically establish and control a
secure tunnel through the Internet to your company's Juniper Networks
NetScreen VPN appliance. The problem here is that the address space
conflict meant that, as soon as your 3COM Gigabit adapter received its
IP address, the NetScreen Remote client would become active and take
over the exact same address space. Therefore, requests (such as pings,
etc.) intended for other machines in your local network, were instead
being sent to the VPN interface. As those IP addresses do not exist in
the company network at the other end of the tunnel, you would get no
response whatsoever.
A possible remedy, depending on how your company has configured the
security policies for the NetScreen Remote client, is to change the
address that the client listens on. You have inferred this already by
suggesting that you change the address of either the client, or the
local network.
I am going to recommend that you leave the client alone for now, and
change the local network instead. This means that you will not need to
fiddle with the settings in Windows for VPN, with the potential to
'break' it.
To change the local network, use a connected PC to access the
web-based configuration interface of the Visionnet 202ER-4, at
10.0.0.2.
After you have logged in, go to the LAN Configuration screen. Here,
you will see several items that will need to be changed. The first is
the DHCP address space from which the router assigns dynamic IP
addresses to your network devices. Please change this from the factory
defaults to the range of:
192.168.10.3 to 192.168.10.32
Yes, we are moving completely away from the 10.0.0.x subnet for your local network.
Next, for the LAN IP address of the Visionnet 202ER-4, change it from
10.0.0.2 to 192.168.10.2, subnet mask 255.255.255.0. Leave the other
settings as they were, and submit the changes.
At this point, you will need to allow the router to restart, then you
will need to use the "ipconfig /release" and "ipconfig /renew"
commands to reacquire an IP address on your PCs (note that in W98, the
command is "winipcfg", for W2K/XP it is "ipconfig").
Now, your new computer should be set up to access the local network
resources through the 192.168.10.x subnet, and your NetScreen Remote
client through the existing 10.0.0.x address. One potential problem
here is that it is possible for your company's IT department to
configure your VPN user profile such that the NetScreen Remote client
would prevent 'Internet' traffic while active. So, if even after you
change the local network's address space, you are only able to access
the other PCs and the Internet with NetScreen disabled, that would be
the reason. This capability exists as an optional security measure to
prevent your PC from being a conduit between the Internet and the
corporate network.
--------------------------
One final note, regarding subnet masks. The mask is a binary mask,
meaning that if you write out an IP address in binary, and the mask in
binary, then anywhere that the mask has a 0, your PC will treat as
being accessible through that IP address' gateway. Obviously, I cannot
do this explanation justice using just words... and being a firm
believer in not reinventing the wheel, I will instead suggest that you
take advantage of this excellent resource available on (where else?)
the World Wide Web:
A Free Lecture-based Educational Course on IP Addressing and Subnetting
http://www.learntosubnet.com/
Also,
Learn to Subnet
http://www.cramsession.com/articles/files/learn-to-subnet-part-i----9162003-1529.asp
--------------------------
Please, do let me know if you run into further problems trying to get
your local network's IP address range changed. As for the NetScreen
Remote, you may want to enquire with your company IT department to see
if they can tell you whether your user profile allows you to access
your local network while the VPN tunnel is active.
Regards,
aht-ga
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