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Charles IamsFlag for United States of America

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VPN disconnecting

I'm using a Sonicwall TZ 170 and I'm attempting to VPN into our network from a remote site (ex: a coffee shop). I open Sonicwall Global VPN Client, click enable. It prompts that I have been connect successfully. Then I attempt to connect to our server, for anywhere from 10 seconds to 2 minutes it works perfectly! Then nothing works. I can't even ping our server or any other workstations. I've check the log of the client, windows logs, and the log on the Sonicwall and there are no errors.
I've looked through the Sonicwall getting started guide and manual; it appears everything is configured correctly.

I ran a test to try to see if the disconnection was a timed occurrence and it doesn't appear to be.  I timed from the moment that I was prompted that the VPN connection was established until I was no longer able to ping the server. These are the timespans (mm:ss).
1:45
0:12
1:27
0:30
0:38
0:20

With no errors, I'm clueless on where to look next.

Thanks in advance.
Avatar of xDUCKx
xDUCKx

When you ping -t during the timeout you get a "Request Timed Out" and it won't recover?

Are you connecting via wireless or wired?  Are you able to try each and see if the results are the same?
Avatar of Charles Iams

ASKER

Request timed out.

I've been doing all of my testing over wired currently.
One of our engineers does it over wireless and it appears he has the same exact issue. But I will grab my laptop and give it a try.
Did a quick google to see how to change to verbose logging on your sonicwall model and found this:

https://www.sonicwall.com/downloads/site_to_site_vpn_troubleshooting_on_sonicwall_security_appliances.pdf

It seems to address this issue exactly.  Have you seen this and tried the steps/solution?
I attempted everything that could have been the issue and nothing worked. But I found something in the process.

On the VPN client, if I go to properties of the VPN connection there is a status tab and I have the option to renew the Virtual IP. If I wait until "ping server -t" shows "Request Timed Out", then click renew. I get a reply on the ping immediately and it works for another 10 seconds- 2 minutes.
I haven't looked into it yet but I imagine its something in the DHCP server. I'm done for the night on this, I will take a look tomorrow, I will post back what I find out.
Avatar of Syed Muhammad Usman
Dear,

if you are using SNA-TZ series as DHCP, than by default DHCP lease times on the SonicWALL is 1440 minutes. In a more mobile network this can pose a problem.  
can you try to lower the lease time to 2-4 hours..

please also verify you are NOT using static DHCP lease... pelase also clear arp entries in your SNA.
I'm not using the Sonicwall for DHCP. DHCP is handled by a Windows SBS '03 server.
Any additional thoughts? I've been trying to solve this all morning and I haven't made any progress. I've been looking on google but I can't find anyone that has had this issue.
Interestingly if I reserve an IP on the DHCP server for a specific computer, it doesn't drop the connection anymore. I'm going to test this on a few more computers tonight.
could you please check the elased time of SBS? what are the TCP/IP properties etting of the client? are you using Domain Credintial? is there any GPO or policy preveting idle clients or ....... :)
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Charles Iams
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Thanks for the update.
No solution as of right now. I will revisit this in approximately a month.