Nortel Networks NN46110-602 - Manual (Page 70)

70 Chapter 4 Troubleshooting
NN46110-602
Troubleshooting remote access problems typically starts at the client end when the
remote user cannot establish a connection, loses a connection, or has difficulty
browsing the network or printing. When connectivity problems occur and the
source of the problem is unknown, it is usually best to follow the OSI network
architecture layers. Therefore, start diagnosing the physical environment, the
modem, and the cables before moving up to the network and application layers
(for example, pinging a host and Web browsing).
As with connectivity, there are many places in the extranet network where
network performance is affected. By regularly checking the network statistics,
logs, and health check information, and by informing users of good network
practices, you can often avoid problems and enhance the productivity of the
extranet.
General problems are categorized here as problems other than those related to
connectivity or network performance. For the latest release-specific problems,
check the release notes.
Troubleshooting tools
For the VPN Router administrator, a robust troubleshooting toolbox is filled with
both standard and special tools for diagnosing network problems. Standard tools
like Telnet, PING, Trace Route (tracert.exe), sniffers, and analyzers are a basic
necessity. To this collection, some special tools are added to the VPN Router
manager and remote client applications. These special tools include client- and
VPN Router-based tools.
Client-based tools
IPsec VPN Client Monitor provides network statistics on device, connection, and
network errors that help monitor traffic flow and assess IPsec connection
performance. Statistic counters are updated once a second. For more information
on the IPsec VPN Client Monitor, see the VPN Client online Help.