Notebook – CEF

CEF - Cisco Express Forwarding
-Both routers and Layer 3 switch both have IOS routing software.
-Software Routing is slow compared to ASICs
L3 switching can use a software and hardware method to move data.
FIB - Fowarding Information Base - Caches Routing Information from the Router supervisor
ADJ Table "routes" (fowards) frames out a port based on mac address information.
ASIC is a name for a switches hardware.
CEF takes L3 routing informaion and caches it to the FIB.
As the switch is booting up, it will look for all the next hop addresses in the routing table
 and pull the MAC addresses from the addresses.
This information is then sent to the adjacency table with all the necessary ARP information.
CEF only tracks routed ports (or interface vlans)
Exceptions to CEF:
Packets with Header options
Packets with TTL expired
Packets destined to use tunnel interfaces
Packets with unsupported encapsulations
Packets required fragmentaion (MTU Exceeded)
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to turn on CEF:
switch(config)#ip cef
CEF has a feature to watch all traffic statistics.
Will only work for routed interface vlans

show ip cef vlan 200:
shows what ips have been learned by CEF in vlan 200.
ex output:
switch#show ip cef vlan 151
192.168.0.0/24
 attached to Vlan151
The 192.168.0.0/24 was learned on vlan 151
switch#show ip cef 192.168.0.25
192.168.0.25/32
 receive

show ip arp x.x.x.x
shows arp information for the specified IP address, and what interface it was learned on.
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CCENT Acquired.

Well, I passed my CCENT! This is the ICND 1 Portion of the CCNA. So I’m half way there. I was hoping to have my CCNA by now, but medical complications changed that. Nonetheless I will be studying the ICND 2 portion and updating my studies on my blog now. I barely did any for the ICND 1 because I just needed to hurry up and get it done.

Dennis Ritchie, pioneer of Unix, dies at 70

Another, but even more, terrible loss in the tech community. Dennis Ritchie, the pioneer of Unix and C programming passes away at 70. He was a true genius who’s passing has gone widely unnoticed. This is quite sad, that while millions of people would mourn the loss of Steve Jobs, almost none of them even know who this man is. If it weren’t for him, there would be a lot of technological innovations not seen today.

R.I.P. Dennis Ritchie.

http://www.engadget.com/2011/10/13/dennis-ritchie-pioneer-of-c-programming-language-and-unix-repo/?a_dgi=aolshare_facebook

Steve Jobs Dies at 56.

Apple Founder and Former CEO Steve Jobs dies at 56

I am no fan of Apple, but I did have a lot of respect for Steve Jobs.  He was an innovator, a visionary, set industry standards, and built a great empire. He had a dream and was not afraid to go after it, and in doing so, he succeeded. R.I.P. Steve Jobs.

Cancer took it’s toll on him and its sad to see such a thing happen.
(It might even happen to me one day too, if my cancer decides to show itself.)

Battlefield 3 Beta

So the Battlefield 3 beta is out right now (Get started with the beta if you haven’t yet!) (Also get that pre-order in!) . I am completely enthralled with it at the moment.
I’ve been playing this for PC, and yes I have Origin. If you feel like joining me in a game, hit me up, my ID is GorathKaiga.
So far I’ve been loving it. People need to realize, ITS A BETA, so don’t judge how much you like or dislike this title based on the beta. Of course you’re going to see bugs of course you’re going to see imbalance, and of course you’re going to experience problems playing the game overall on your hardware. You may experience problems with ATI/Nvidia cards? Thats fine, go download the beta drivers they have out.

I am currently running an MSI GTX560Ti, with the beta driver, and have so far had no crashes. I’ve run into a few  bugs with the game, but not with the game crashing on me or performance issues.

Find your Nvidia BETA drivers here.

(Don’t ask me about ATI/AMD drivers.)

But I will say, Dice has done a hell of a job with this game. I’m loving it, and can’t wait for the final release. October 29th

Out of hospital!

I have just been released from hospital, this means I can start working on my studies again. I have just completed Part 1 of my Cisco IOS commands. There will probably be about 2 or 3 parts to this, don’t know.

What I do know is, now that I am out, and in recovery, there is nothing else I can do so I will be doing some heavy studying and updating my blog with new notes. As soon as I’m out of recovery I hope to go sit my CCENT exam, then shortly there after my CCNA.

Thanks to all for your support.

In Hospital

Right now, I’m in hospital, and will be here for  about 3-4 days, so between now and then there won’t be any of my Notes. I just had an operation done on my back. (no studying).

However, I still may do some occasional posts here and there. I can’t study for obvious reasons, hospitals are just not conducive to studying, plus this pain medication makes me tired. 🙂