Network Testing and Troubleshooting
Once network configuration is complete, you will need to test network connectivity and address any problems that may arise. Here is an example testing scheme:
Verify that the network hardware is working by examining any status lights on the adapter and switch or hub.
Check basicnetwork connectivity using the
pingcommand. Be sure to use IP addresses instead of hostnames so you are not dependent on DNS.
Test name resolution using ping with hostnames or
nslookup(see Section 8.1).
Check routing by pinging hosts beyond the local subnet (but inside the firewall).
Test higher-level protocol connectivity by using
telnetto a remote host. If this fails, be sure that
inetdis running, that the
telnetdaemon is enabled, and that the remote host from which you are attempting to connect is allowed to do so (
inetdis discussed in Chapter 8).
If appropriate, verify that other protocols are working. For example, use a browser to test the web server and/or proxy setup. If there are problems, verify that the browser itself is configured properly by attempting to view a local page.
Test any network servers that are present on the local system (see Chapter 8).
The first step is to test the network setup and connection with
ping is a simple utility that will tell you
whether the connection is working and the basic setup is correct. It
takes a remote hostname or IP address as its argument:
ping hamletPING hamlet: 56 data bytes 64 bytes from 220.127.116.11: ...