Novell LINUX ENTERPRISE SERVER 10 - INSTALLATION AND ADMINISTRATION 11-05-2007 Installation Manual page 610

To display all devices, use ip link ls. To display the running interfaces only, use
ip link ls up. To print interface statistics for a device, enter ip -s link
ls device_name. To view addresses of your devices, enter ip addr. In the output
of the ip addr, also find information about MAC addresses of your devices. To show
all routes, use ip route show.
For more information about using ip, enter ip help or see the ip(8) man page. The
help option is also available for all ip objects. If, for example, you want to read help
for ip addr, enter ip addr help. Find the ip manual in /usr/share/doc/
packages/iproute2/ip-cref.pdf.
Testing a Connection with ping
The ping command is the standard tool for testing whether a TCP/IP connection works.
It uses the ICMP protocol to send a small data packet, ECHO_REQUEST datagram,
to the destination host, requesting an immediate reply. If this works, ping displays a
message to that effect, which indicates that the network link is basically functioning.
ping does more than test only the function of the connection between two computers:
it also provides some basic information about the quality of the connection. In Exam-
ple 30.10, "Output of the Command ping" (page 593), you can see an example of the
ping output. The second-to-last line contains information about number of transmitted
packets, packet loss, and total time of ping running.
As the destination, you can use a hostname or IP address, for example,
ping example.com or ping 130.57.5.75. The program sends packets until
you press Ctrl + C .
If you only need to check the functionality of the connection, you can limit the number
of the packets with the -c option. For example to limit ping to three packets, enter
ping -c 3 192.168.0.
592 Installation and Administration