IPv6 SLAAC and DNS Overview | Cisco CCNA 200-301

🏃🏼‍♀️🏃🏼‍♂️💨 In a hurry, timestamps (below) allow you to jump to the part you want to see now.
🆓 Free Packet Tracer Labs download: thekeithbarker.com
🦘 Jump links:
01:00 The benefits of auto-address assignment
02:00 How Statless Address Auto Configuration works in IPv6
03:20 Packet Capture of IPv6 Router Advertisement (RA)
05:50 IPv6 Stateful DHCP defined
07:30 How to let the client know to use DHCP for other options (like DNS)
09:00 Explanation of the "M" and "O" bits in a Router Advertisement (RA)
12:00 How to set the M and O bits, in a Packet Tracer lab
24:58 Quick summary
Enjoy, Like, and Subscribe. 😃
Free KZbin Playlists from Keith:
▶ Master Playlist for Cisco CCNA 200-301 ogit.online/sloth
🔐 Cisco CCNA 200-301 Security ogit.online/200-301_Security
💻 Cisco CCNA 200-301 IPv4 Subnetting ogit.online/subnet
💬 Join our Discord server ogit.online/Join_OGIT_on_Discord
And…
🏫 Keith’s Content at CBT Nuggets ogit.online/Keith-CBT
#KeithBarker #CCNA #200-301

[@anwarahmed5342]

When Keith explains a topic he will give all details in a very clear and short way, one hour with Keith is just like 5 minutes, awesome tips, thank you man.

[@KeithBarker]

Glad to help

[@Oghuzian]

I'm already a CCIE and know this by heart, but I still find myself drifting back to Kieth's videos as I love them and they got me to where I'm now. Good on you mate!

[@keithjiang6617]

Thank you very much, Keith. You solved the confusion about the difference of SLAAC and DHCP which was in my mind for years.

[@godzab]

I am a huge fan of you setting up the lab as you go, instead of having a pre-made lab. Helps drill in the basics while building upon new concepts. Thanks for these videos!

[@debraneighbors8764]

Thank you!! You posted this and the next video just as I got to that part of my CCNA training. Perfect!! You've made it all so much clearer.

[@KeithBarker]

Glad it was helpful!

[@avivmaimon8068]

I admit, that in studying for the CCNA exam within the chapter of IPV6, what was not clear to me and understood at all was SLAAC. This video of yours just made it clear and understandably smooth !!!! Thank you so much Keith.

[@KeithBarker]

Thank you אביב מימון Aviv Maimon!

[@drockqx]

Thank you. I'm studying for my Net+ certification right now. I only watched the first half, but I now understand this topic much better.

[@KeithBarker]

Thank you Derrek James! Happy studies.

[@waynescott1528]

Thanks Keith, this was very informative!!!! Thank you for taking the time to explain the concepts and demo on the lab equipment!!!!!😃😃😃

[@GordonFadie]

Great explanation and walk thru! Glad something went wrong and we got to see some troubleshooting. It's better than watching something go 100% smooth and trying to retain it.

[@KeithBarker]

Glad you enjoyed it

[@Sv35511]

thanks for the lab practice. theory was driving me crazy, Also the way you troubleshoot things are impressive. Love your channel!!

[@KeithBarker]

Glad to hear it! Thank you Safal Vadassery!

[@simbadurio444]

A thousand thanks Keith. Entertaining and informational as always.

[@samjones4327]

Thank you Keith! I've enjoyed learning about a few of the aspects of IPv6!!! Thank you for explaining and showing how this topic works! Cheers!

[@Siqzs]

Hey Keith, thanks for this little refresh of my CCNA. Convenient in these times. Stay safe!

[@KeithBarker]

Thank you Siqzs!

[@amosfeldman9454]

Amazing Video Keith!! Thank's for doing my requested video. How awesome.

[@KeithBarker]

Thanks for the idea Amos!

[@alexandercullum6632]

thank you for the info! all these videos are needed in depth nuggets to go along with what I'm already learning!

[@KeithBarker]

Glad it was helpful!

[@sasukedebonaire2375]

Hey bro just a wanted to know you’re saving me right now during my ccna 🤣😎 preciate u fam 👍🏼

[@KeithBarker]

Happy to help

[@tg9460]

Thanks again Keith. Refreshing as always.

[@KeithBarker]

Very welcome

[@juanmartinayonacarrera2190]

thank you for videos Keith Barker!! Hi from Lima Peru.

[@zoltron30]

Whew! Labbed this with physical gear... never seen this before. Really awesome stuff Keith.

[@KeithBarker]

Thank you zoltron30!

[@kylemlsantos97]

This was the most fun I have had in packet tracer, you rule!!!!!!!!

[@KeithBarker]

Thank you @kylemlsantos97!

[@84dhampir]

Thank you Keith I'm studying to take CCNA exam and this topic was driving me crazy, I subscribe to your channel my friend

[@KeithBarker]

Thank you Eden Rene Salazar Ordoñez! Welcome aboard. I have an "Instructor Hour" on Discord every Saturday, 10am pacific, and an online quiz every Sunday at 11am Pacific. Would love to see you at those live events. Happy studies.

[@ryancarnes2110]

Slaac has been a real struggle for me for some reason . Thanks for clearing some things up for me. I just subscribed 😁

[@KeithBarker]

Thanks for the sub!

[@marciobritodonascimento2683]

thanks a bunch ! Keith!! you are the guy!!

[@teunb1574]

This is a great video! Learned so much which wasn't clear to me with the plain text study material from Cisco.

[@matthewngen8747]

you're one of the best network routing and switching masters out there. in our lives, we do meet rubbish people here and there. don't let it affect our hair and i hope you see what i'm saying. your crewcut hairstyle in the past still the best hairdo.

[@KeithBarker]

Thank you Matthew Ngen!

[@7085Chris]

Another great video, many thanks Keith.

[@KeithBarker]

Many thanks

[@KhalidBaeisa]

Thanks Keith!!

[@michaelanderson7902]

Thank you very much Keith!

[@KeithBarker]

You got it. Thanks for the feedback Michael

[@zchantzis]

You are my hero man.All the best thank you

[@KeithBarker]

Thank you Chow Chow!

[@soccers856]

Your channel is amazing. Thank you so much

[@KeithBarker]

Wow Thank You Walid El War!

[@kalross73]

Great explanation. Thanks.

[@KeithBarker]

Happy to do it, thanks for the feedback Kal Ross.

[@fhamidkhan]

Thank you Keith.

[@KeithBarker]

Happy to do it, thanks for the feedback

[@rubinhamzi]

Amazing, I learned a lot, Thank you very much 🙏🙏🙏

[@KeithBarker]

So glad!

[@anonymoususer6786]

Just don’t stop learning!!!!!!!!! 🤘🏼🤘🏼🤘🏼

[@ramdogproductions]

So great!!

[@KeithBarker]

Thank you ramdogproductions!

[@gponciano1757]

too good!!

[@themistoclesnelson2163]

Thanks Keith!

[@KeithBarker]

Happy to do it, thanks for the feedback Themistocles Nelson.

[@arshamrezaei8918]

this guy is so cool. thanks for your great help man.

[@KeithBarker]

Thanks for watching!

[@user-px6lz5gr6m]

Great video, thanks !

[@KeithBarker]

Glad you liked it!

[@linuxmanju]

Brilliant, thank you🙏

[@KeithBarker]

You're most welcome!

[@annakustra9869]

awesome, thanks!

[@KeithBarker]

You bet!

[@nessd665]

Great video

[@KeithBarker]

Thanks!

[@und3rgr0undfr34k]

awesome!! thnx

[@KeithBarker]

You're welcome!

[@Arayankodesouth]

awesome...thankyou..!

[@KeithBarker]

Welcome 😊

[@tetotamimi6681]

The best

[@KeithBarker]

Thank you teto tamimi!

[@swtpeteswtpete1515]

Great video, so useful in augmenting my use and understanding from my class' shell's Cisco CCNA2 own online study materials, specifically their interactive slides.. I was a little stuck on the DHCP v6 homework tonight, and your presentation was superb. Q1. When you did "do show run," I **did** see the nd managed flag set; did you ever find out why it disappeared or how? Had you needed to do a "no shut" in order to make the setting stick?? Q2. Why did Cisco with its iOS reinvent DHCPv6 vs not simply model it on DHCPv4? It seems they made it quite more complicated than it needs to be. (Aside, I was surprised to learn that the TCP STACK settings are static, DHCP, and then this third option called auto config! I guess I never noticed that before.} Q3. One thing you did not mention in this video, would the admin ever set both the M *and* O flags to 1, or is it always either-or, only either of the two is ever set to a one? Anywhooo, thanks for a wonderful video and I look forward to watching several others of yours.

[@sasikanthvipparla1243]

Thank you!!! Found very helpful IPv6 Host autoconfiguration process. If possible post video or any pointers for IPV6 router autoconfiguration process.

[@KeithBarker]

Thank you Sasikanth Vipparla!

[@saifssj]

Great work as always! Thanks for your hard work! I am sure you get this question a lot but, I wanted to know if all the videos you have posted in the ccna master playlist at the moment is enough for sitting for the exam? I see it is still being updated, does that mean there are more videos left for it to be complete? If you could please elaborate, thank you

[@KeithBarker]

Unfortunately no. This playlist is intended to augment or assist whatever your main study material is. There is a lot about cabling, and connector types, that I will likely never cover here on KZbin, which are still relevant tot he CCNA 200-301. Hope that adds some clarity, and than you for the question and for watching. Happy studies, and much success to you!

[@saifssj]

@@KeithBarker Thank you kindly for your reply. Aside from the cabling etc. stuff you have mentioned, every thing else is covered in this playlist? Is there anything else missing is there anything extra? Sorry for the bother.

[@KeithBarker]

@@saifssj I would suggest downloading the blueprint directly from Cisco, to identify everything that is required. Here is the direct link www.cisco.com/content/dam/en_us/training-events/le31/le46/cln/marketing/exam-topics/200-301-CCNA.pdf Happy studies.

[@ceylonecreativetv7512]

Good

[@marciopriess3999]

I have a question, what happens if the router has only a link local address in the interface? With no global address in the interface, what would happen?

[@Karlsmarten]

Why would we use SLAAC over DHCPv6?

[@KeithBarker]

Thank you for the question Jeppe. Less overhead with the assignment and renewal of leases, and SLAAC does a reliable job of getting an address and gateway information on it's own. So I suppose the benefits include less overhead and less moving parts.

[@vheverett]

Nice Keith, when will SLAAC get the ability to set DNS natively? Is there an RFC for that ?

[@KeithBarker]

Thank you for the question Vin Everett. The RFCs (plural) are out, it is just a matter of IOS version and development. Cisco does have some products that support it now.

[@surge3158]

If the host is configuring its own IPv6 address (stateless), how does it make sure it isn't reusing an address that already exists on the local subnet? Or does it not matter because of the link-local addresses

[@KeithBarker]

Thank you for the question Surge315. The IPv6 host uses a process called Duplicate Address Detection, (or as his friends call him, "DAD") to confirm there isn't a local duplicate address.

[@leothalion3983]

Keith, when creating a dhcp pool, is the POOL its a command?

[@KeithBarker]

Thank you for the question Jose M. ip dhcp pool MYPOOLNAME that is the syntax. Let me know if that helps.

[@jeffersonumana4137]

Hi Keith! I am studying this topic of IPv6 and watching this video in the minute 19:31 exactly, I saw something that I cannot understand. The physical address of the PC is 0001.43A7.D633, then, the PC generates the IPv6 address using EUI-64 using that MAC Address and squeeze an FFFE in the middle. Speaking about the Link-Local, it displays the FE80::201:43FF:FEA7:D633. What I want to know is about the #2 in that Link-Local address (FE80::-->2

[@KeithBarker]

Thank you for the question Jefferson Umaña. There is a really sorted history on the why, which in the end it doesn't matter too much, other than the fact that for the EUI-64, the 7th bit from the left is flipped as it goes into the link local address. Example: Hex 0 0 0 1 . 43 etc Binary 0000 0000 0000 0001 . 43 etc Binary with 7th bit flipped 0000 0010 0000 0001. 43 etc Hex with 7th bit flipped 0 2 0 1 . 43 etc Thanks again for the question, and happy studies.

[@Hehhnsbz2334]

@@KeithBarker Sordid, not sorted. As of October, 2022, IPv6 remains to be sorted. The matter of the "universal/local bit," a/k/a the "u" bit, being flipped is discussed in pp. 8-9 of RFC 2373, "IP Version 6 Addressing Architecture." "It is required that the 'u' bit (universal/local bit in IEEE EUI-64 terminology) be inverted when forming the interface identifier from the EUI-64. The "u" bit is set to one (1) to indicate global scope, and it is set to zero (0) to indicate local scope.... "The motivation for inverting the 'u' bit when forming the interface identifier is to make it easy for system administrators to hand configure local scope identifiers when hardware tokens are not available. This is expected to be case for serial links, tunnel end-points, etc. The alternative would have been for these to be of the form 0200:0:0:1, 0200:0:0:2, etc., instead of the much simpler ::1, ::2, etc. "The use of the universal/local bit in the IEEE EUI-64 identifier is to allow development of future technology that can take advantage of interface identifiers with global scope." RFC 2373 has been superseded by RFC 4291, but this part stayed the same. See pages 7-8 of RFC 4291.

[@KeithBarker]

@@Hehhnsbz2334 Watch you go! That is awesome, thank you.

[@zaherer2008]

Thanks Keith , is it possible to tell what software you use to write on the screen ?

[@KeithBarker]

Thank you for the question, I use epic pen. epic-pen.com/ Cheers.

[@zaherer2008]

@@KeithBarker Thanks a lot

[@clarkgaylord]

Generally excellent content However: bzzzt on the crossover cable. GigE, for basically as long as anyone has been putting hosts on gigE links, autosenses polarity and need not have crossover. The *very* early gbic based gigE interfaces needed this but that has long since been an anachronism.

[@alessandrobonifacio1209]

Ciao Keith! where is it possible to see a calendar of your live streams?thax!

[@KeithBarker]

Thank you Alessandro Bonifacio! The Office Hour on discord: Each Saturday, 10am Pacific ogit.online/Join_OGIT_on_Discord The Live Stream Quiz sessions on KZbin: Each Sunday, 11am Pacific time That's it. Hope to see you soon, and thanks for the interest.

[@alessandrobonifacio1209]

@@KeithBarker legend

[@HiPh0Plover1]

can you confirm the flags dont mean shit to the host ? it's just like suggestions arent they ? like it wont force the host to use that option will it ?

[@KeithBarker]

Thank you for the question Happy Turtle. It depends on the client OS, and what it will do based on the flags present. Not every platform responds exactly the same to those flags.

[@James_Knott]

DNS info can be handed out with RDNSS, which has been around for years. I've been running pfsense for over 6.5 years and use RDNSS. Android devices don't support DHCPv6. Also, you don't need crossover cables with Gb and some 100 Mb NICs.

[@KeithBarker]

Thank you James Knott!

[@tahersadeghi6773]

How does the pc in this video say "Hey, is there a router out there?"

[@KeithBarker]

Thank you for the question Taher Sadeghi. In IPv6 that request is done via the RS (Router Solicitation), as part of the Neighbor Discovery Protocol (NDP).

[@shurato00]

Hey Keith, strangely my pc didn't get the DNS IPv6 address

[@KeithBarker]

Thank you trying the lab Allanzr. Sometime PT is a bit finicky. Sometimes, saving the lab then closing and reopening can assist when the lab isn't working as expected, and you think it may be a Packet Tracer issuse. Happy continued studies!

[@shurato00]

@@KeithBarker Thank YOU Keith, I think this is one of the most interesting contents about CCNA I've seen since I started.

[@sujithkuruvilla9873]

Please make a video on BGP

[@KeithBarker]

Thank you Sujith for your interest. I have a few BGP videos here on KZbin, primarily related to MPLS L3 VPNs. Currently I am working on mostly CCNA related content for this KZbin channel. I appreciate your interest, and wish you the best of success in your studies and career!

[@parheliaa]

Each and every time I read about SLAAC I can't comprehend this RA gives rarely usable things like MTU, but the DNS address (crucial information, along with Address and Gateway) is supposed to be taken from an external server? WTF?

[@KeithBarker]

I hear you! This RFC, when implemented by the vendors on their gear, will help. tools.ietf.org/html/rfc8106

[@DevilWearsAdidas]

how the hell do you write that nice with a computer marker? xD

[@KeithBarker]

Thank you 0011thhour! Lots of practice.

[@vanpeters9751]

Or option 43

[@HAsmaa-zg6rt]

hhhhhhhhhhhhh (ME: why wont he write outside the img) HEE I CAN WRITE OUT HERE ToO

[@ceylonecreativetv7512]

Good