can you subnet a subnet and can those subnets be different sizes the answer is yes you'll be given a network like this 172.21.42.0 a slash 24 Network and Bernard hackwell the CEO of hackwell Industries is telling you to address a new Factory they have he needs four networks a guest robots servers and workers Network each with their own different host requirements and all you have is a slash 24 get to work slice it up how you gonna do that can you even do that yes with a little magic called vlsm or variable link subnet mask variable meaning that the networks we're cutting up might be a different size and in this case they are now I do have good news you no longer suck at subnetting right if you've watched this entire series you're pretty good and while this is your final Challenge and it will be a challenge you have the skills so get your coffee ready get all the skills and knowledge you've learned in the past episodes we're gonna combine all of that the power of coffee and subnetting to solve this problem let's do this [Music] so let's look at our networks and Tackle our problem each one of these has different host requirements as we mentioned before totaling roughly about I don't know how many 10 57 210 hosts which is good because uh the network we were given can only accommodate 253 hosts row slash 24 remember so it's possible but how are we doing here's how we do it I don't know why I have two fingers up it's kind of weird we do it the same way we've always done it a vlsm is the same as all the subnetting you've learned you just have to approach it in a different way for example when doing this you'll want to start with the largest host requirement first so looking at our stuff here the largest Network we have is the r is the workers with 117 hosts we need that's our host requirement let's subnet now again you've been here before if you've watched our series we're going to be subnetting the 172 2142 zero Network slash 24 based on host requirements so let's call in our friends we need to know Serato of course to cover our subnet mask from decimal to Binary help us out Nosferatu thank you see it's easy and we can't forget his brother nosfra 2 and step one of our subnetting process will help us figure out how many host bits we have to hack so we'll bring in our nose raw 2 chart which is just double the size of our nosferaw 2 chart and we'll start to subnet 117 host which according to nosefront 2 we're gonna need one two three four five six seven hostess we're gonna hack seven host bits and because we're submitting based on host requirements we're going to go to the upside down and save the host and right now I'm gonna go very fast because you've already been here before now I don't want to waste your time so on our current mask we're going to save every host but the last one we're gonna let him get hacked giving us our new subnet masks a slash 25 and a dotted decimal here's what we look like and if we throw that last octet onto the noserato chart we can see our increment is 128. let's build our Network again we've been here before 172 2142 0 through 172 2142 127 and that's the network for our workers but here's where it might trip you up you might be like okay what next what do I do I was tracking with you until now it is actually not too bad you just pick up where you left off and you start with the largest next like when you're doing vlsm you go from Big to small so the largest host requirements to the smallest host requirements next on our list what do we got we got the robots So Many Robots robots I don't know we'll ask questions later what could be the harm now real quick I do want to thank our Siri sponsor boson software they're the reason this thing can be free on YouTube they're amazing and they're really amazing at practice exams like this question right here can you get this right I doubt it no actually you probably can you know you no longer suck I said many at least after the end of this video check this out this is from their CCNA practice exam which you can take right here in your browser so cool they give you a subnet and they say hey which one of these hosts is valid on that subnet here's a question if you know it comment below and if you want more of this to actually get ready for the CCNA and take it and pass it and become amazing check it out link below I use boson to pass my exams and they've supported me my entire time being full-time in YouTube they're amazing anyways back to back to subnet so we pick up where we left off where we leave off well we got 172.21.42.128 and we go from there that's the network address let's take it over here to our worksheet and we'll even use the same mask a slash 25 and again our robots have a host requirement of 57 hosts does Frosty give us our mask in binary please thank you though Serato now I'm gonna speed around this you're gonna see these things moving on my screen right now because you already know how to do this I just want to show you how we go through the process how we jump to that next subnet with our new subnet mask we've got a slash 26 255-255-255-192 the increment is 64. which should more than economate Academy accommodate our robot overlords subnetting so to build our Network we'll start where we left off 128 plus 64 we've got 191 and that is our Network for the robot overlords they forced me to say that 172 2142 128 26. now at this point I hope you're seeing how it's coming together it's weird but we're just starting from biggest to smallest and we're just submitting each Network in order based on the host requirements go and do the rest yourself do our guest and server networks pause the video unpause how'd you do I think you did great but let's see real quick now again we're just gonna pick up where we left off which was 192. now I'm not going to go through the entire southerning process again but you would have started out with this address or this network and this subnet mask with a host requirement of 26 for our servers and just something at that by the end of it we should have an increment of 32 a slash 27 subnet mask also known as 255.255.255.224 and if we build that Network out it's gonna be 192 ending in 2 2 3 223 and there's the subnet for our servers and I'll go and draw on the guest right now 224-28 ending in two three nine now if you got that right that's fantastic you just did blsm subnet which again is a lot of what we've already learned in the series because what we did here was just subnet based on host requirements four times we just kind of had to approach it in a weird way big to small and starting where we leave off each network but honestly it's kind of crazy when you look at it right like we got slash 28 26 27 25 and we cut that all up from a slash 24. that's impressive if you did that and really I'm kind of at the end of what I can teach you you I can confidently say no longer suck at subnetting now it doesn't mean you won't forget everything you learned here as soon as you walk away because that will happen it happens to me at least you probably need some practice for that check out Network Chuck Academy I've got a link below joining me on that Academy you'll get some extra practice extra quiz questions that can help you polish up sharpen these subnetting skills because skill you have to develop over time and trust me you're gonna forget this you don't have to come back and learn it every year or so like I do now also learning subnetting is a skill you'll take with you into many of the networking problems you'll have to solve so for example uh our series sponsor boson software if you jump into their boson XM the best practice exam software in the world you're gonna hit questions that are very very similar to the CCNA questions that will require you to subnet and it won't just say please subnet this no it's going to say like what's wrong on this network why isn't this access list working I'm telling you this is a core skill you're gonna bring with you so if you want to test yourself get on Bose on XM to see how you how you do also there are bows on netsim they're Network simulator they're going to give you laps building networks right in your browser dude you can be chilling on your couch with your iPad networking nothing better than that except you know you need a cup of coffee then you're good but seriously check out boson below they have made this entire CCNA series possible including this you suck at submitting series and I'm sad to say the series is now over just the stub netting part there's more CCNA to come but subnetting like I said you learned all I can teach you now go learn it again