Tag Archives: Logical Switch

DEEP DIVING INTO NSX – A FEW BASICS

Redoing my home lab is always fun, but its a lot more fun when NSX comes into the mix. It all started with this customer who wanted NSX so bad.. well here I am trying to find out why?

Let me be honest, I am NOT a networking guru. It has almost always been one giving me headaches but NSX feels so refreshing and easy enough to wrap my head around it.

So heres a quick refresher for two most important components – I don’t talk about all the components here, only a few for now but more on their way.

1. Segment IDS – Segment IDs, as Wahl rightly puts it, are like VLANs for you VXLAN. Imagine having multiple NSX Management servers talking to a single vcenter, their traffic will be separated by the segment ids – is one use case. Now for each VXLAN virtual wire you get one segment ID assigned to it. So how many segment IDS are allowed? 16 billion! Yes 16 billion of them. So that we don’t get confused with the physical VLAN ids – the segment ids start with 5000. Now I created 5 Segment IDS from 5000 to 5005. Also remember this is a system wide setting!

segment-id

2. Transport Zone – Transport zones are basically Network scopes in VCNS, if you recall what they are. Let me explain, when you create a transport zone you add a cluster to it. This basically defines the scope of that VXLAN virtual wire. If you have 5 clusters that need to be able to access the same VXLAN virtual wires then they need to be part of the same Transport Zone.

3. Logical Switches – Logical switches are virtual wires – basically VXLANs. When you create a logical switch you assign it to a transport zone. This allows all clusters that belong to the same transport zone to be now configured/exposed to that logical switch. This allows VM’s in a cluster to be able to talk to each other on this VXLAN logical wire without having to create a physical vlan. Remember once a logical switch is created you cannot change its transport zone. You will have to remove it and recreate it to change its transport zone.

logical-switch

More to come keep you posted 🙂