Cisco Wireless LAN Controller (WLC) Interface Groups

last week on the discord server we were having a great discussion about wi-fi and wireless networking and the question came up hey what if we've got thousands of users in a building one wi-fi network or one ssid with lots of aps and that good stuff how do we make sure that we don't have too many people chunked into like one vlan when that traffic hits the wired network that's a great question and that's the question that you and i get to answer in this video so let me start by giving you delay of the land for the network here i've got vlan one which is my home network it's just easier to manage devices there and then i created vs 10 20 and 30 with these ip address ranges respectively and these are all slash 24s i then got a 3750x that i got on ebay for pretty cheap and it has a whole bunch of ports it's also supporting power over ethernet then i took port 13 14 15 and 16 which is really gig 2 0 13 14 15 16 and i connected them over to the wireless lan controller which is a 2504 on its ports one two three and four and that way we could support lag which i'll show you here in just a moment i also took these two ports 25 and 26 and i assigned them to vlan 30 and that's where i put the aps and the wireless lan controller itself is being managed on vlan 1. so in the big pictures these aps get powered on just by connecting with power over ethernet they boot up they have to discover where is the wireless lan controller and then build a cap wap tunnel over to it which is over here on vlan one and then start providing the services also for the access points i got some 3702 eyes that i also got on ebay so let me share with you some of the details that i had to configure on the switch to provide the dhcp services and the routing and oh my goodness wait do you see this option 43 did not go as cleanly or smoothly as i thought it would with ios's dhcp so here on the 3750 this just show ip interface brief and what i did here was i created four vlan interfaces switched virtual interfaces on this switch and i assigned it these addresses respectively so it's basically going to be the default gateway for vlan 30 vlan 20 vlan 10. so i set this router up as a dsp server for vlan 10 vlan 20 and vlan 30 and i supplied its own ip address as the default gateway and check this out for vlan 30 where i put the access points i added option 43 now a couple things i want to point out about that option 43 why do we need it well option 43 tells an access point what is the ip address of the controller so it can call home sync up join that controller and become part of the family and here's the syntax option 43 then the keyword hex this specified was hex and then i put in this value right here in fact i didn't put the periods in it added that for me i also tried a couple other options with the keyword ip where i thought i could just put in the ip address but i was looking at the log files on the access point and it was not having it it could not locate it so here's what this is this is a t l v for type length and value the first character i just looked it up online is f1 for the access point that i'm using and then the length is four bytes long so i put two characters there with a zero and a four representing four bytes that's the ip address is four bytes long then i put the value which is this bad boy right here and the way i calculated that was i took the ip address of 192.168.1.77 which is the ip address of the controller and i got out the scientific calculator this is built into the current version of windows i went to this menu and i said i want to look at the programmer option and then i i went to decimal and i put in 192. and it said great in hex that's going to be c0 so i put in c0 for those first two characters and then i cleared that off and i said okay the next octet next byte is 168 which is in hex a8 and i put that in so basically this is just c080149 is the hexadecimal representation of this iep address tricky though right here where it has the zero one it's gonna be two hex characters representing eight bits so if the value is one or something only takes one hex character put in that leading zero so it knows exactly what you're talking about so once i put this option in and then the access point renewed a type address it could find the controller it said so on a console message and then it joined the controller and we were off to the races so just be aware that you may have to do a little bit of trickery if you're working with ios's dhcp services to hand off that option 43. these interfaces 13 14 15 and 16 that go over to the wireless line controller let me show you those interfaces and here they are in all their beauty so these four interfaces go over to the wireless lan controller it's four interfaces and so here what i did was two basic things number one i specified that they were trunks now my switch it also supports isl so i specified one queue so there wouldn't be any mistake there i told it was a trunk and then i told this interface 13 14 15 and 16 those four interfaces that they were going to be part of this ether channel group number one and then i used mode on which is the correct mode to use if you're doing ether channel over to a wireless lan controller and the question might come up well keith if this is what you did on the switch that goes over to the controller what do you need to do on the controller to go ahead and use link aggregation great question let me show you exactly what we would do so here on the controller itself let me just check real quick make sure my access points are there great they are they both checked in if we just click on the controller tab right here and then down here on the left click on ports just want to verify that all four ports are connected that's great these are connected to those four ports on the switch and then if you go to general so on the controller tab you go to general right here there's an option for lag mode on the next reboot now what i did was i simply said enable it said hey please save this reboot the wireless lan controller and now it's going to be active and that's exactly what i did so that's why it says right here link aggregation mode is currently enabled so the benefit of this is all those four ports currently they're all happy happy but if we lose a link or there's a problem link aggregation will use the remaining interfaces to go ahead and still communicate it's wonderful and now the part that we've been waiting for what if we have thousands of clients that are all being connected via wireless when their traffic hits our networks we don't want all that traffic all those users being one single vlan how do we spread that out and the answer to that question is to use interfaces and interface groups let me show you exactly what i mean so here on the wireless controller if we click on the controller tab over on the left we have an option for interfaces now what i did was just a few moments ago i created three new dynamic interfaces let me show you how that would go we'd slide all the way over to the right i've made this screen fit so i could present it click on new and let's say we want to create a new interface we'll call it interface 4 just for grains and i will put a capital i just to keep it consistent and then it's asking oh hey this new logical interface what 802.1 q tag what vlan id do you want to associate with it so if we were going to support vlan 60 we could put a 60 right here and click on apply and boom we now have this new interface called interface 4 which is going to be supporting vlan 60. now here under the physical information because we're using link aggregation we don't have to say use port 1 or port 2 or port 3 because our wireless lan controller is using link aggregation and all four ports are available currently and then if we scroll down here vlan identifier 60 because we put that in earlier and we're going to create here what's i'd like to think of it like a switched virtual interface on a switch where it's just a logical ip address in that space so if that is the 10.60 network and we're going to use dot 254 we'd put in that ip address that represents this wireless lan controller on that network and then we'd put in the mask and then we just put in the default gateway address for that subnet and then the primary dhcp server in my environment i'm using my multi-layer switch as the default gateway and the dhcp server so i put 10.60.0.1 for dhcp server and then scroll up and click on apply in the upper right corner click on ok and if we go back to interfaces we now have the management interface the three that were there from a few minutes ago and the one that we just created if we want to get rid of it we can just go over here hover and then say remove click on ok and boom that logical interface is no longer there oh i deleted 30. bummer all right i'm going to delete the one that we just created two's enough for what we want to demonstrate anyway so we have interface 10 interface 20. now if we went to wireless networks and i have one wireless network wi-fi one and we edited that wi-fi network here under interface interface groups the default is management that's our management interface however if we wanted to associate this wifi network with interface 10 which is associated with vlan 10 or interface 20 which is associated with vlan 20 we can simply select those but if we wanted to load balance let's say we have a two or three hundred clients that are coming in and we wanted to load balance them across maybe vlan 10 and vlan 20. here's what we could do instead of selecting one of those here here's what we could do go back to controller and the left hand side go down to interface groups check this out so we'll click on interface groups there aren't any by default and what we'll do is we'll simply say hey we want to create a new group of interfaces and let's call this our group and we'll put vlan 10 and vlan 20. we could say vlan 32 but i deleted that interface and then we'll click on add and then we have that vlan group and now we'll add interfaces so we could add interface 10 it's showing up here click add shows up in the list there's interface 20 click on add and now this interface group called our group includes the logical interface 10 and logical interface 20 which effectively means vlan 10 and vlan 20. so we'll click on apply and then we'll go back to our wireless lans and then we'll edit our single wi-fi network then what we'll do is we'll say under here interface or interface groups with the drop down we'll say our group and then we'll click on apply so now what's going to happen is as that traffic comes in the wireless lan controller can load balance or round robin or use whatever mechanism it's going to use to send some of that traffic and associate some of that traffic with vlan 10 and other traffic with vlan 20 once it hits our wired networks so there you have it my friend we have the ability with interface groups to associate that with an ssid and then as traffic comes in the system the wireless line controller can divvy up that traffic respectively between the two or more interfaces that are part of that group so that's it for this video i'll see you in the next one meanwhile be well be happy and be nice to everybody bye for now you

Channel: Keith Barker

Views: 13,733

Rating: 4.9524941 out of 5

Keywords: ccna, cisco, 200-301, Cisco CCNA, Cisco Certification, ogit, Keith Barker, cisco wireless controller, cisco wireless controller training, cisco wireless lan controller, cisco wireless lan controller configuration, cisco wlc tutorial, wireless lan controller, cisco wlc configuration, cisco wireless

Id: BYL5Ud8ABvM

Length: 11min 8sec (668 seconds)

Published: Sat Aug 01 2020