VLAN BASICS

hi this is a brocade campus feature explainer series I'm Terry Henry this time we're gonna talk about VLAN basics so how to configure tagged interfaces and untagged interfaces and how to see you know what what VLAN and interface is in etc and so this applies to I'm doing this on the IC X series but it also applies to anything in the fast iron series the ml X YZ the CER the CES so they're pretty much all the same with the exception of the VD x line everything else gets configured exactly the same way so this is a cross-platform so from my console here if I look at the default running configuration if I just do a show run here well the only thing non default is that I have a hostname but otherwise everything is in the default VLAN and the default VLAN is is VLAN 1 you can change that default VLAN and so if we look at show VLAN here we can see that all of my ports there's only one VLAN currently created there's a maximum of 64 now that doesn't mean this hardware is only capable of 64 the hardware is capable of 4,000 94 however there's only enough memory allocated for 64 so we needed to allocate more memory you could use the system max command and reload the device to reallocate the cams there's a separate video on that on system acts and show default values but for most enterprises 64 VLANs on an edge switches far more than enough so then we see VLAN 1 it's our default VLAN spanning tree is off on this currently we can see because I'm running router code spanning tree is disabled by default so then we can see my ports so unit 1 module 1 port 1 to 12 port 13 to 24 so these are my one 10/100/1000 ports and then module 2 which are my 10 gig ports so unit 1 module 2 ports 1 to 8 or the 10 gig port so these are all untagged by default in the default VLAN we have no tag ports we have no uplink ports we have no dual mode ports we have no mac VLAN ports and there is no monitoring on this feel and currently configured and so by default everything is in this VLAN they can switch among each other so if that's what you're going for then then you're done however in most cases the default VLAN is just somewhere where we put ports that are not allocated to another VLAN right so normally we're gonna put our ports into a VLAN for data for voice you know printers by department however you're gonna allocate your VLANs so your up links are generally going to be tagged so from switch to switch they're going to be tagged out to a say a PC is gonna be untag does that end device doesn't understand tagging and so to define tag versus untagged it literally means in the in this in the packet as it egress is a switch port we literally insert a tag into the into the packet header to say this packet belongs to VLAN 100 or 200 or whatever the case and so the device at the other end reads that tag and understands what VLAN or what broadcast domain that packet belongs to if it's untagged then that means that we don't insert any VLAN number so the receiving side that doesn't understand VLANs can still process the packet if we send tag frames to a device that is untagged it's gonna throw those packets away right because it doesn't understand VLAN tagging so one of the anomalies with VLAN 1 well by design actually is that we won't let you tag the default VLAN or VLAN one so if you use VLAN 1 in your environment and it's something that needs to be tagged out to other devices say Cisco devices running in a tag native VLAN they and you need to change the default VLAN in order to be able to tag you than one so for example if I go into config T here and I go into VLAN one and I try to tag an interface a tagged Ethernet 1 / 1 / 1 it's going to refuse to let me do that right so if I wanted to do that I would just change my default VLAN to you know something in the high number 4000 or something you're not gonna utilize otherwise okay so how do we create a VLAN pretty straightforward if I want to create VLAN 10 I can just say VLAN 10 and now optionally I can add a name in there so I could say name data so it's always a good practice right so I now have a VLAN called data but there's no ports in it at this point so if I wanted to move some ports into it let's say I wanted to untag Ethernet 1 / 1 / 1 and I could do arrange - 1 / 1 / 12 for example so it system comes back and tells me that it's added those ports 1 1 1 2 1 1 12 - VLAN 10 and will tag an uplink so let's say we tagged Ethernet 1 / 2 / 1 which is one of the 10 gig ports on my 10 gig module okay so now let's create us a say a voice VLAN so we'll say VLAN 20 name voice the name is optional right you don't have to have that and we will we'll untag e 1 / 1 / 13 - 1 / 1 / 24 for example now normally with voice VLANs those are going to be tagged and that's something called dual mode so if you're tagged and untagged on the same interface at the same time we call that dual mode and that requires special handling so there's another video in this series that specifically talks about how to do dual mode VLANs but I'm not going to talk about at this point so then we're going to tag that same uplink because let's say that's going that an uplink to our data center so we will tag Ethernet 1/2 / 1 so the same port that we tagged in the previous feeling so now if we do a show VLAN what we're gonna see here we still have our VLAN 1 right and so the only ports left in VLAN 1 now are 1 / 2 / 2 - 1 / 2 / 8 all of the other ports we've moved somewhere else so as soon as you put a port in another VLAN other than the default it automatically takes it out of that default VLAN and vice versa when I remove it from any other VLAN it'll automatically go back to VLAN 1 so that's not something that I need to manually do so here's our here's our 4 VLAN 10 right port 1 / 1 / 1 - 1 / 1 / 12 our untag + 1 / 2 / 1 is tagged and the same thing on VLAN 21 1 13 to 1 1 24 + 1 - 1 is tagged also if we look at an interface a show interface e 1 / 1 / 1 for example it's going to tell me that it's a member of layer 2 VLAN ID 10 the port is untag and it's port state is blocking now that's it's it's blocking because the port is down at this one if we look at one of the tagging interfaces so 1 / 2 / 1 we can see that it's a member of 2 layer 2 VLANs support is tagged and its port state is forwarding so that port is actually up at this point so it's in a forwarding state ok and so if I go ahead and let's say I want to remove a port so no untag e 1 / 1 / 13 for example so I'll remove that out of eelan 20 so now if we go back and look at do a show VLAN 1 / 1 / 13 is now back in the default so I didn't need to do anything the other thing to bear in mind of course is that because this is right I'm running router code spanning tree is disabled by default so you most likely want to go into each one of those VLANs and turn on per VLAN spanning tree or more likely rapid spanning tree so span 802 1w give it a priority so span tree root bridge party obviously depending on where that is in your environment going to VLAN 20 and we're gonna do the same thing so span 802 span 802 so it's 802 - 1w is what that stands for so now if in the show VLAN it's now going to tell me that spanning tree is on for those VLANs okay so that's the basics - VLANs obviously if you want to route between VLANs there's another video on that to create a router interface to be able to route between VLANs dual mode if you want to tag a none tag on the same time so for phones or sometimes access points there's a video on that as well in the series but that's the basics to how VLANs work so thanks for joining and see you next

Channel: Terry Henry

Views: 7,365

Rating: 5 out of 5

Keywords: Arris, ICX, MLXe, Ruckus Wireless, Ruckus, Network, Ethernet, FastIron, Brocade, Wifi, BRCD, Networking

Id: -OvRb4gE8js

Length: 9min 58sec (598 seconds)

Published: Wed Oct 05 2016