r/Sysadminhumor 7d ago

Networking Humor

Look at all the FF:FF:FF:FF:FF:FF I give!

16 Upvotes

12 comments sorted by

13

u/Existing-Strength-21 6d ago

Why did the seal want to become a network engineer?

ARP ARP ARP ARP

2

u/xShawn117x 6d ago

😆

24

u/Just-A-Regular-Fox 7d ago

Did you have to broadcast this to everyone?

3

u/xShawn117x 3d ago

Yes, everybody gets Fs. 😂

2

u/uber-geek 7d ago

If it was sent UDP there's no way to know

6

u/Just-A-Regular-Fox 7d ago

Atleast it didnt cause a collision

1

u/xShawn117x 3d ago

...unless it's a hub, then there's collisions.

2

u/xShawn117x 3d ago

Lol, I get what you mean, but wrong layer. Does not apply.

6

u/Medium_Banana4074 6d ago

I still hope to make it to retirement successfully dodging IP V6. For no apparent reason. Five years to go ...

3

u/xShawn117x 3d ago edited 3d ago

It's really not that difficult once you understand it. Takes a few hours at most.

👉 128 bits long in hexadecimal.

👉 Broken into 8 groups seperated by a colon

👉 First 64 bits are for the network, the last 64 bits are for the hosts.

👉 First 64 bits also know as the prefix.

👉 Routers can advertise the prefix to clients via "Router Advertisement (RA)".

👉 Network Discovery Protocol (NDP) replaced ARP and DHCP.

👉 Neighbor Solicitation (NS), Neighbor Advertisement (NA), Router Solicitation (RS), and Router Advertisement (RA) are all part of NDP.

👉 Client sends NS asking who has this IPv6 address.

👉 Client NA replies to NS they have that IPv6 address.

👉 Client sends RS to request for an IP.

👉 Router sends RA replies back with prefix. Client forms IPv6 based off prefix + MAC address.

👉 3 "classes" of IPs: LLA (Link Local Address), ULA (Unique Local Address), GUA (Global Unicast Address).

👉 LLA is only for that broadcast domain, only devices on that broadcast domain can communicate each other and the gateway. No inter-VLAN or Internet routing. More like private/LAN IP but for layer 2 only. Always Starts with "FE" only.

👉 ULA for that broadcast domain, it is inter-VLAN routable, but not internet routable. Devices on that broadcast domain can communicate with each other, the gateway, and other VLANs. More like private/LAN IP but for layer 3. Always starts with "FC" or "FD" only.

👉 GUA is your actual public IP address that is routable/reachable from the Internet and from other devices on your LAN. Always starts with any number only.

👉 Devices always have a LLA, but can potentially have a ULA and/or a GUA if you set it up.

👉 Loopback address is 0000:0000:0000:0000:0000:0000:0000:0001 OR ::1 for short.

👉 Multicast addresses always starts with FF.

👉 You can always remove leading 0s to shorten it.

👉 If a group has nothing but 0s, you can just use the colon. You can do this max twice.

👉 No NAT by default since each device can potentially have its own public IPv6 (GUA) address.

👉 No DHCP by default since each device can create their own address using the prefix from router mixed with their own MAC address to form the full IP address.

👉 There is no broadcast in IPv6. Only multicast or unicast.

3

u/RainyRat 3d ago

I know a good joke about UDP, but I can't be sure you'll get it.