I read tutorial about VLAN configuring. The author talks about VLAN id and uses it in following actions:
My VLAN ID is 5. So I need to copy file /etc/sysconfig/network-scripts/ifcfg-eth0 to /etc/sysconfig/network-scripts/ifcfg-eth0.5
I can't find information about why VLAN id is 5 in this case? How do I know what is VLAN id in my case? And from what VLAN id depends? I run Ubuntu 12.04 if it important.