Dynamic VLANs...

r_durant

Is it widely used in the real world? Does CCNA go deep into it?

I haven't seen much talk about the subject in the forum (if any at all) or the text....

Netstudent

Nah you will not see any dynamic VLANs on the CCNA. You need high end switches that are VMPS capable, in which case would be beyond the scope of CCNA. It is an interesting topic though, it's just hard to learn without the gear.

I'v read about some open source VMPS programs on a unix box. If you are interested maybe you can look into that.

mikearama

I've worked in three enterprise environments, and in all three, the senior admins scoffed at the idea of dynamic vlans.

At my current gig, the previous admin employed them, only to find the task of constantly adding mac address to the db onerous and frustrating. It ended up being delegated to the implementations team, who screwed it up more often then they got it right.

I think it would be interesting to use, and if initially setup properly (ie, the mac's were entered correctly the first time), could be a time saver. And I noticed that CiscoWorks has a module for creating and using dynamic vlans.

Not only are dvlans not covered in the ccna (other than a cursory mention), they are also not part of the BCMSN course/exam.

Mike

dtlokee

Dynamic VLANs have fallen out of favor because of the amount of administration required to manage the MAC addresses. Dynamic VLANs are not really a security measure because the MAC address is easily spoofed and it would allow users to hop onto other VLANs. 802.1x authentication would be a better choice to achieve security and dynamic VLANs on a network, but it is not a topic on the CCNA, so for now, don't worry about it.

r_durant

It does seem like a cool concept, once you can get it right as Mike said...but glad to know it's not on the CCNA...