I am researching Quantum with Open vSwitch, and am wondering if someone can answer this question for me.
When should i choose GRE or VLAN for the networking and what pros and cons will i have in using one of them compared to the other?
Hey there buddy,
There's one thing that will always make GRE a better choice than VLAN is physical switch configuration. When you use VLANs, you have to setup your switch ports for trunking. Also, you have to ensure those VLANs exists on your switch.
Even more, let's say you're in my case whereby you have a main distribution switch with multiple edge switches. Then you have to ensure those VLANs exists on your distribution switch and your edge switch. So let's say you have 100 customers, and you enable them to create networks. For sake of estimation, let's say each customer creates 2 networks, then you need to ensure 200 VLANs exists on your switch, otherwise things will not work such as DHCP, VM to VM communication on different nodes etc.
Stay away from VLANs if you can, go with GRE, it's simpler to implement and manage.
Recommend to read > http://www.slideshare.net/randybias/networking-is-not-free-lessons-in-network-design
Asked: 2013-06-12 08:23:40 -0600
Seen: 1,349 times
Last updated: Feb 06 '14
