I've been pretty good about keeping a regular study schedule. My classes have been pre-recorded, for the most part, so it's easy to procrastinate. "Why do today, that which you can put off until tomorrow?" has been my mantra for many years. Tough habit to break. So, I scheduled my CCNA test for two weeks from today. If I put the date on this blog, I figure I have to keep it. Very excited. Going back through the labs and practice exams from my classes, reading my notes, hitting Chris Bryant videos, and labs at freeccnaworkbook.
Can't wait to walk out of there with a pass! (Positive energy..)
Friday, June 22, 2012
Monday, June 18, 2012
Master IP Subnetting Forever
I agree with Chris Bryant at The Bryant Advantage. You should know how to subnet using binary. Knowing that, I went through his binary conversion and subnetting course, and learned it well. Practiced every day at subnettingquestions.com, until I no longer made silly errors, and it made sense to me.
But as exam day neared, I worried that I would be too slow with all of these binary conversions. I also found that when I hurried my conversions, the silly errors returned. In my studies on the Cisco Learning Network, I saw people referring to an "increment of 16", or an "increment of 32". What does that mean? I found out here: Master IP Subnetting Forever. The "magic box" is a huge timesaver.
This document is truly a lifesaver, along with the "thumb rule". I don't remember where I learned it, but when it comes to the "power of two", the thumb rule is great. When trying to figure out "2 to the 5th power", stick your thumb out. That's two, or "2 to the 1st", now start doubling the number, extending a finger each time. 4, 8, 16, 32. When you get to your fifth finger, you are at 32. "2 to the 5th" is 32. Now, if you are counting available host addresses, subtract 2. Five host bits gives us 30 hosts per network.
Just keep counting, and keep doubling. "2 to the 10th" is 1024, or 1022 hosts. Easy stuff. But again, learn how to do it in binary first. You should always know how to do it at the fundamental level, so when you forget the "trick" or the "magic box" you can fall back on the basics.
But as exam day neared, I worried that I would be too slow with all of these binary conversions. I also found that when I hurried my conversions, the silly errors returned. In my studies on the Cisco Learning Network, I saw people referring to an "increment of 16", or an "increment of 32". What does that mean? I found out here: Master IP Subnetting Forever. The "magic box" is a huge timesaver.
This document is truly a lifesaver, along with the "thumb rule". I don't remember where I learned it, but when it comes to the "power of two", the thumb rule is great. When trying to figure out "2 to the 5th power", stick your thumb out. That's two, or "2 to the 1st", now start doubling the number, extending a finger each time. 4, 8, 16, 32. When you get to your fifth finger, you are at 32. "2 to the 5th" is 32. Now, if you are counting available host addresses, subtract 2. Five host bits gives us 30 hosts per network.
Just keep counting, and keep doubling. "2 to the 10th" is 1024, or 1022 hosts. Easy stuff. But again, learn how to do it in binary first. You should always know how to do it at the fundamental level, so when you forget the "trick" or the "magic box" you can fall back on the basics.
Why won't my 3750x stack upgrade automatically?
I received 11 new 3750x switches the other day, and was excited to hear that, with the Stackwise cables installed, I could just upgrade the master to the latest IOS, and it would upgrade all the other switches in the stack automatically. This would save me quite a bit of time and effort versus tftp'ing the ios over to each one individually.
So, like a kid on Christmas morning, I stacked up five of them on the bench, hooked up my laptop to the master, and copied the .bin file over, and waited. And waited. And moved the console cable down to the second switch, and nothing. None of the switches were doing anything. The consultant I had working on my new firewalls said "That should work". But nothing. Tried a couple reloads, still nothing.
Called Cisco and opened a ticket. The TAC tech was very nice, but going on vacation for a couple days. I manually upgraded the first batch of switches, as they were going in that night. Did a bunch of research on the internet while waiting for the TAC to get back to me. Found this article:
Cisco 3750 Stack Upgrade
In the article, I found that for the automatic upgrade to occur, I needed the .tar file, not the .bin file. I downloaded the .tar file, put it in my tftp root folder, and ran this command:
archive download-sw tftp://11.11.11.11/c3750-i5-tar.122-20.SE.tar
then, I watched in amazement as the master upgraded, and then upgraded the other three switches in the stack. It upgraded the boot path for me as well, and deleted the old IOS. Ready to go!
Well, almost. It seems that once you stack a switch, it remembers it's number. When I went to rack those switches that night, the switch that I brought up third kept insisting that it was number four, and that it was the master. Not good. This meant that interfaces 4/0/1 through 48 would actually be on the third switch, and vice-versa. Two commands fixed my issues here:
To make sure Switch1 is always the master, I set it's priority to 15:
conf t
switch 1 priority 15
To renumber Switch4 to 3, and Switch3 to 4, I renumbered them:
conf t
switch 3 renumber 4
switch 4 renumber 3
Then I reloaded the stack to make all this take effect.
reload
You can also reload specific switches in the stack:
reload slot current slot number
More info here:
Creation and Management of Cisco 3750 Stacks
So, like a kid on Christmas morning, I stacked up five of them on the bench, hooked up my laptop to the master, and copied the .bin file over, and waited. And waited. And moved the console cable down to the second switch, and nothing. None of the switches were doing anything. The consultant I had working on my new firewalls said "That should work". But nothing. Tried a couple reloads, still nothing.
Called Cisco and opened a ticket. The TAC tech was very nice, but going on vacation for a couple days. I manually upgraded the first batch of switches, as they were going in that night. Did a bunch of research on the internet while waiting for the TAC to get back to me. Found this article:
Cisco 3750 Stack Upgrade
In the article, I found that for the automatic upgrade to occur, I needed the .tar file, not the .bin file. I downloaded the .tar file, put it in my tftp root folder, and ran this command:
archive download-sw tftp://11.11.11.11/c3750-i5-tar.122-20.SE.tar
then, I watched in amazement as the master upgraded, and then upgraded the other three switches in the stack. It upgraded the boot path for me as well, and deleted the old IOS. Ready to go!
Well, almost. It seems that once you stack a switch, it remembers it's number. When I went to rack those switches that night, the switch that I brought up third kept insisting that it was number four, and that it was the master. Not good. This meant that interfaces 4/0/1 through 48 would actually be on the third switch, and vice-versa. Two commands fixed my issues here:
To make sure Switch1 is always the master, I set it's priority to 15:
conf t
switch 1 priority 15
To renumber Switch4 to 3, and Switch3 to 4, I renumbered them:
conf t
switch 3 renumber 4
switch 4 renumber 3
Then I reloaded the stack to make all this take effect.
reload
You can also reload specific switches in the stack:
reload slot current slot number
More info here:
Creation and Management of Cisco 3750 Stacks
Sunday, June 17, 2012
Training Resources
I am a big fan of Knowledgenet. They offer live online classes, as well as recorded classes. They use official Cisco curriculum, and it is refreshed regularly. The training is not just a series of videos-- you get the book, and they have very realistic labs and pre and post-assessment exams integrated into their training. Highly recommend them.
Also love Chris Bryant's CCNA program. If work isn't paying for your classes, and you find that a couple thousand dollars is too much, then you are in luck. The Bryant Advantage is very in-depth, very thorough, and Chris is a personable guy. A dry instructor can really make this curriculum boring. Chris doesn't do that. He keeps the material interesting, and he has a ton of three to five minute videos that hit the point and get out. Do a couple each day on your coffee break. Follow him on Twitter, Youtube, or hit his blog. The free videos he gives away each day are worth it alone. For not a lot of money, you can pick up his CCNA or CCNP video series and study guide. Although I can't speak to his CCNP material yet, I have the CCNA guide and video series, and love them both. It is a quality program at a fraction of the price you would pay elsewhere. He demos everything on live equipment, and really does a great job of explaining the material. Also highly recommend Chris!
LearnSmart (formerly PrepLogic)... Hmmmmm. Really enjoyed the CCNA program for the short time I was subscribed. I like the layout, the organization of the site, the progress clocks and projected completion dates. But, near as I can tell, the books are not official Cisco curriculum, and they have a lot of complaints on the web from people who apparently didn't read the fine print-- myself included. I don't think they are a bad or malicious organization, and from what I've been told they have really been working hard to clean up their image. I had some trouble initially getting my money back on a "30 day money back guarantee", but they did come through for me and make it right. I will say, however-- read the fine print-- even if the sales guy tells you that you have a 30 day "no questions asked" return. If the contract says no refunds, then be prepared to not get your money back, no matter what the sales guy said. Like I told their guy on the phone the other day. I don't have a problem with their training. I really liked most of it. But things like automatic renewals are a big red flag to me, especially now. Provide a quality product, be upfront and honest, and instill trust in your clients, and they will come back-- voluntarily.
Also love Chris Bryant's CCNA program. If work isn't paying for your classes, and you find that a couple thousand dollars is too much, then you are in luck. The Bryant Advantage is very in-depth, very thorough, and Chris is a personable guy. A dry instructor can really make this curriculum boring. Chris doesn't do that. He keeps the material interesting, and he has a ton of three to five minute videos that hit the point and get out. Do a couple each day on your coffee break. Follow him on Twitter, Youtube, or hit his blog. The free videos he gives away each day are worth it alone. For not a lot of money, you can pick up his CCNA or CCNP video series and study guide. Although I can't speak to his CCNP material yet, I have the CCNA guide and video series, and love them both. It is a quality program at a fraction of the price you would pay elsewhere. He demos everything on live equipment, and really does a great job of explaining the material. Also highly recommend Chris!
LearnSmart (formerly PrepLogic)... Hmmmmm. Really enjoyed the CCNA program for the short time I was subscribed. I like the layout, the organization of the site, the progress clocks and projected completion dates. But, near as I can tell, the books are not official Cisco curriculum, and they have a lot of complaints on the web from people who apparently didn't read the fine print-- myself included. I don't think they are a bad or malicious organization, and from what I've been told they have really been working hard to clean up their image. I had some trouble initially getting my money back on a "30 day money back guarantee", but they did come through for me and make it right. I will say, however-- read the fine print-- even if the sales guy tells you that you have a 30 day "no questions asked" return. If the contract says no refunds, then be prepared to not get your money back, no matter what the sales guy said. Like I told their guy on the phone the other day. I don't have a problem with their training. I really liked most of it. But things like automatic renewals are a big red flag to me, especially now. Provide a quality product, be upfront and honest, and instill trust in your clients, and they will come back-- voluntarily.
My Journey Begins..
Welcome!
Don't let the URL fool you, I am not a CCIE. I'm just barely a CCENT. But my goal is to be a CCIE, so this blog will serve to motivate me, organize my thoughts and resources, and maybe help you out, if we are both lucky. I just have a ton of notes, links, thoughts, and other semi-useful information laying about, and want to organize it. Typing it into my blog is just another way to study the material, and having it around forever is an added plus.
So, hang around, or check back. Feel free to drop me a line if there is something you would like to see here, or if you are on the Cisco journey as well, and would like to compare notes.
Craig
Don't let the URL fool you, I am not a CCIE. I'm just barely a CCENT. But my goal is to be a CCIE, so this blog will serve to motivate me, organize my thoughts and resources, and maybe help you out, if we are both lucky. I just have a ton of notes, links, thoughts, and other semi-useful information laying about, and want to organize it. Typing it into my blog is just another way to study the material, and having it around forever is an added plus.
So, hang around, or check back. Feel free to drop me a line if there is something you would like to see here, or if you are on the Cisco journey as well, and would like to compare notes.
Craig
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