A local area network can have up to 10% of its network activity collide and still be considered acceptable, but on modern-day switched networks, collisions should be near zero. It's very simple to determine the collision rate. You need two pieces of information: the number of collisions and the number of network card output packets. If you have root access, run the ifconfig command. Figure 4-24 is a sample ifconfig output. For Ethernet card eth0, since the system was rebooted, there have been 31 collisions and millions of packets both sent and received. The percentage of collisions in relation to both incoming and outgoing traffic is far below 1%. No problem there!

If you don't have root access, try the netstat command. If you're not familiar with the netstat command you may need the help of your network administrator to figure out how to get collisions and output packets to appear. The netstat manual page can be overwhelming. Simply divide the number of collisions by the number of output packets, and ensure it is well below 1%. If it's not, contact your network administrator immediately.

Figure 4-24. This is an example of an ifconfig command run to determine if network collisions are a problem. From both an inbound and outbound perspective, collisions are well below 1%.