vNetworks seem to be the most confusing topic so far...

multi paths, port groups, vswitches, cisco nexus, integration with physical networks etc.... have you guys found this to be the most complex topic?

question: If my vswitch has different vlans, how is the physical switch configured to indicate that?

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jmritenour

tdean wrote: »

multi paths, port groups, vswitches, cisco nexus, integration with physical networks etc.... have you guys found this to be the most complex topic?

question: If my vswitch has different vlans, how is the physical switch configured to indicate that?

Yes, networking vSphere is by far the hardest topic to soak up, mostly because a lot of it flies in the face of physical networking, or VMWare uses well known terms from physical networking in completely different ways.

As for the question about VLANS on a vSwitch and how it corresponds to a physical switch, you want to use the same VLAN ids on your physical and virtual switches, and make sure the physical NIC on your ESX that will be handling your VM data traffic is plugged into a trunked port on the switch that will carry traffic for for any VLAN ids being tagged on the virtual switch.

One way to look at is is that the VLAN tags on the virtual switch would be almost like subinterfaces on a router - all traffic is going through the same physical port, but the vswitch knows how and where to send traffic based on the tag.

Hope that helps!

tdean

jmritenour wrote: »

Yes, networking vSphere is by far the hardest topic to soak up, mostly because a lot of it flies in the face of physical networking, or VMWare uses well known terms from physical networking in completely different ways.

As for the question about VLANS on a vSwitch and how it corresponds to a physical switch, you want to use the same VLAN ids on your physical and virtual switches, and make sure the physical NIC on your ESX that will be handling your VM data traffic is plugged into a trunked port on the switch that will carry traffic for for any VLAN ids being tagged on the virtual switch.

One way to look at is is that the VLAN tags on the virtual switch would be almost like subinterfaces on a router - all traffic is going through the same physical port, but the vswitch knows how and where to send traffic based on the tag.

Hope that helps!

ok, that solves half my question.... back to the vlans... foe example, if you have 4 port groups, or a single dswitch with 4 vlans, each with a range of 4 ports (just to make it easy)... you'd have to have the same amount of vlans and ports in each vlan on the physical switch?

i hope im explaining this right...

MentholMoose

It may help to just imagine a vSwitch as another physical switch. The physical switch ports the uplinks are connected to should be configured as trunks, and any VLANs on port groups that need to go somewhere on the physical network should be configured on the trunk (physical switch port). You can have any number of physical switch ports configured as access ports in a particular VLAN. You might even not have any physical switch ports configured as access ports for a VLAN, such as if traffic on a port group is only going to VMs on other VMware hosts.

jmritenour

tdean wrote: »

ok, that solves half my question.... back to the vlans... foe example, if you have 4 port groups, or a single dswitch with 4 vlans, each with a range of 4 ports (just to make it easy)... you'd have to have the same amount of vlans and ports in each vlan on the physical switch?

i hope im explaining this right...

No, it's not a one to one sort of thing. Typically, you'd have many ports on the virtual side to a much smaller number of physical ports. It is very possible to have just one port dedicated to VM traffic on a physical switch per each ESX host, with several VMs sending traffic through it.

This document might shed some light on it. Quite frankly, I found VMWare's PDFs on their site to be one of the best VCP study materials.

tdean

thanks guys.... let me look this stuff over and see where i am. im sure i'll have more questions this weekend.

rwwest7

Just pretend it's a real switch. If you want multiple vlans on a real switch what must you do? Trunk the uplink port. The only thing different is you don't have to worry about STP or loops. The kernal will handle all that.

TNStratos201

I agree. The networking portion is difficult for me to the point it's aggravating.

jasonboche

I prefer to think of VMware Networking as powerful and flexible, but I will grant you that it can be quite an advanced topic. Being a CCNA, you should be able to tame it quickly. As others have said, think of the vSwitch as a physical switch. The vDS and Nexus 1000v are the next generation virtual switches which VMware's enterprise features and applications will hinge on.

MentholMoose

For learning networking in vSphere, besides reading about it, do some labbing. With one host (ideally two), a managed switch, and maybe a router, you can configure advanced networks and learn a lot. The network configuration in vSphere Client is GUI-based, which makes it easy to visualize and (at least for me) easier to understand, so labbing really helps.