Cisco Layer 3 Switch - Introduction & Basic config

in this video we're going to be talking about the cisco layer 3 switch more specifically a a 37 50 G switch which I'm on at the moment and what is a layer 3 switch well it's a layer 2 switch as well as layer 3 what do I mean by layer 2 and 3 well the OSI reference model is what I'm referring to their lair to obviously is datalink where traditional switches sit and layer 3 is obviously network which is where IP routing takes place IP addresses are described consider etc so traditionally layer 3 is for routers so by having a layer 3 switch then we've got a normal layer 2 switch and a router in the only one packaging essentially yes that's what we've got so today I'm just going to show you how versatile these switches can be and what you can clean what you can do on them what you can configure it's just gonna be a basic overview not to look too in-depth so let's get into it so did you views though the Cisco's operating system before which set the command-line interface now connected via the console port on the back of the layer 3 switch we've got a regular user mode privilege exit mode and global liberation mode let's give up switch a hostname so the 3 switch and we're going to create an interface now a virtual interface for VLAN 10 so we do interface VLAN 10 IP address zero we don't have to enter no shutdown virtual places up by default and now if we go to show IP and briefed we will see our VLAN 10 interface right here as IP address of one and two and six eight ten dot one and the status is down at the moment not administer flee down just down because there are no ports configured to for VLAN 10 on the switch so now a routed port what the root support meanwhile traditionally or layer Tuesday lay three switches come ship with like with layer two configuration essentially the ports are all in layer two mode so how do we get them out of layer three mode well we going to a port how many nodes 323 and we enter no switch port that has now turned our interface into a layer three root support so we can route in and out of the network via this port now um IP address three zero one thing the layer 3 switch alter by default comes shipped with a configuration on VLAN 1 to get an IP address via DHCP and of course all of our ports are by default in VLAN 1 so it applies to allow you to switch all the ports come ship with them in video 1 so how do we get rid of that what we don't see in 2001 and we do know IP address get rid of the IP address for us yep so we'll go back to our interface now do IP address 10 to 10 and turn up one two three then after winter no shutdown should be up by default and now if we go to we should be yep there we go and we go to show IP breathe we should be able to see there we go so 10 to 10 to 1 2 3 on port 1 0 23 and up and up you might be wondering why there's this extra number here on the interface ports basically the layer 3 this particular model is capable of stacking and stacking is a feature of the layer 3 switches and also layer 2 and the 29 some 2960 models can do come with the stacking as well basically it means that you can group together physically group them to physical switches into one virtual switch so essentially for example if I was to stack this with another model of the same spec I would essentially have 56 ports to configure and what I would see is I'd see one through 1 0 / 1 through 2 1 0 / 28 and then after here I'd see 2 0 / 1 representing this second member of the stack in the stack you have one master and one member or one master and multiple members when a member fouls the master takes over where where would this be useful for us for instance distribution layer switches you had a stack as a call and you've got distribution layer switches and you wants you provide higher at high variability redundancy well we do that with multiple up links to the core from the distribution those switches but rather than taking all the up links into one switch we'd spread them spread one from each distribution I switch into one of each of the physical members of the virtual stack switch and what does that provide well that provides for instance if one of the physical members of the Stan went down the other one stood up that takes over the master role and your distribution no switches can still get out of the network and via the new master switch in the physical stack so basically it's for high availability redundancy purposes and also to expand your switch so if we go back to our configuration now so we've figured a route support and we can get out to eat intimate maybe oh we haven't figured our route sorry so IP routing first of all that's the commands have turned this switch into a routing device and then we can enter our route there's our a 0 and it goes silicon via 1001 so now yeah - yes there we go so what Allah - there I added a default route a static default route to route anything that they switch the routes at inside of the switch doesn't know about suit via 10.10 look 10.1 so access control lists you can compute an appliance control lists on the switch - to control access so what we're doing we can do extended control lists and we're going to permit TCP any-any and we're going to apply this to our virtual interface so IP access group 101 inbound so what have I done there if you're not familiar with access control lists I've applied the access control list 101 which is just a name it doesn't doesn't have any bearing on the effect of the access list except where you put it we're going to permit TCP connections from any source to any destination equal into port 80 HTTP traffic and I've applied that on the inbound direction of the VLAN 10 all the in what is the inbound direction you if you don't know there's inbound and outbound so inbound is if you'll say you you're standing inside of the switch and you're looking out onto the local area network VLAN 10 inbound is traffic coming into that port to be filtered outbound is if you if you're still looking out it's traffic going past you out onto the local area network that's how I like to think for anyway so now let's do a DHCP server IP dhcp pool be around 10 IP address sorry no IP address we're going to do network 190 let's say 10.0 no default Rooter 102 at 16 to one dinner server we going a limit the range IP x need to dress so limits the range we don't want to give out address in this range from the low IP address 1 & 2 1 6 8 10.1 to 191 6 8 10 to 1 9 9 so effectively we have a range from 1 9 2 1 6 8 10 . 200 to 1 and 2 1 6 8 10.25 4 okay well I hope you found all this information informative and I hope it showed you the versatility at the Lathrop spiritual that's only scratching the surface obviously and we've got the routing protocols brutal rip we can do there's two and we can advertise Network smear we can do routes we can do VIP you know the only way you can't do obviously let me explain something to you one second there are flick three flavors of imaging of images rather for the layer 3 switch 3750 at least anyway land base IP base and IP services so the land base is a very limited image allows some way through functionality that's switch virtual interfaces some very minimal routing I believe I've not actually experienced it myself but that's what the Cisco website says IP basis which I'm running here at the moment so that's more advanced routing you can actually you know use routing protocols as I just demonstrated and you've got I P services which allows you to go up to OSPF with a dynamic routing protocols so a few more QoS features IP base also has QoS features yeah how would you find out what image you're running show version right at the bottom of our show version output show you what image you're running is say like a base or land base or IP services um I'll show you the lay two commands we can do G panel one just your regular layer two grants just just for anyone's reference who hasn't actually seen then with you accessing on 10 doesn't exist so create VLAN 10 do spanning tree commands port fast so what a sport fast do allows when the switch boots up and calculate spanning tree or any time scale in this country it won't include that interface in its calculation so the interface will come up straight away yeah that you must do this for all things like servers and hosts printers etc anything that's not a switch basting or links off to a hub essentially is another switch yeah I mean if you're a few shows Marsh I Peru shows you your routing table you can see that 10 to 10 to 10 the reason our switch virtual interface are one or two once you say 10.0 interface is not in there because there's no VLAN ports up on the switch therefore it will not be installed in the routing table because the beat the actual interface of our if you look up in brief the protocol is still down on VLAN 10 so if we were to get up we go into g10 24 and do switch port trunk encapsulation dot1q so you have to choose the encapsulation type on the line 3 switch and there are any two options dot1q and ISL also negotiated but there are two encapsulation types on cue and ISL I say I was not used Cisco proprietary I've never seen it used I've never heard of anyone using it I should imagine days being used somewhere but model day no switch port mode trunk and we don't have to normally if you wanted to limit the amounts of ports sorry VLANs that travel through the trunk space you can go switch port trunk allowed box bill and VLANs and then you just list a VLAN so 10 20 30 well about on but by default they implicit come on exist which says switch port trunk allowed VLAN all we don't need to enter that in toast come up yeah yes so now it's see that it's up because the trunk port is connected to another switch with another truck port sorry that's really I think that's really it really for the layer 3 switching I hope you found it informative let me know if there's anything else I can cover for you but I hope this showing you the versatility to switch what you can do with it please do your feedback in the comments below thanks very much

Channel: Laurence Schoultz

Views: 143,258

Keywords: Cisco, ip, ethernet, switch, hub, router, network, internet, tcp, udp, 802.3, wi-fi, config, layer-3, layer3, layer, layer2

Id: llcw3qjWKQ8

Length: 14min 17sec (857 seconds)

Published: Sat Dec 08 2012