| Event Id | 21171 |
| Source | Microsoft Firewall |
| Description | VPN Connection failure |
| Event Information | This information from some newsgroups may help you: ------------------------------------------------------------------------------ Its failing to get a DHCP address from your router, or your router is blocking traffic, or VPN passthrough is failing in a more subtle fashion. 1. Your router uses IP-based (not MAC-based) rules, so I dont think your firewall is blocking traffic. But there could be an issue with ARP and LAN addressing. Send some traffic from your notebook through your router. Then use the routers "SHOW ARP TABLE" command to see whether your router has an ARP table entry for the MAC address of your notebooks wireless adapter. If not, then its possible that your router doesnt like having two devices (MAC addresses) connected to a single built-in switch port. Try changing the "uplink/normal" button and using a crossover cable from the LAN uplink port to your AP. From the routers perspective, the AP is behaving more like an uplinked LAN than a single device, so maybe this will help. 2. If ARP isnt the problem, then use your notebooks link status to see whether youre getting an IP address from the routers DHCP server. By default the NP15D gives out addresses in the 192.168.168.* subnet. If you see no IP address or an IP address in the 169.254.*.* range, then DHCP is failing. If you suspect your problem is here, try configuring the routers advanced DHCP options to reserve a specific IP address for the MAC address of your notebooks wireless adapter. Consult your routers log to verify the address you specified is being assigned. 3. If neither of these is the problem, then Id suspect the VPN passthrough implementation on your router. VPN passthroughs vary quite a bit, ranging from just letting any IPsec ESP pass in/out to stateful handling of the IPsec tunnel so that arriving ESP packets can be forwarded to the right internal host on the LAN. If the routers VPN passthrough implementation depends on direct connection of the internal host to a |
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