current topology and current focus

I think I’ve figured out part of the problem I’ve been having.  I haven’t been entirely focused on my studies, and I don’t really have a set goal right now.  I’ve been dancing with the idea of skipping the CCNP and going straight to the IE written.  Because of that, I’ve been reading chapters in the IE written exam certification guide, chapters in the BCMSN gook, and still reviewing notes, videos, and chapters from the BSCI studies.

With the way work has been going, I haven’t had as much time to study at work, and I don’t have the office space/time to study at home.  I live in a small apartment, and my rack is sitting in my living room.  I may need to bit the bullet and pay for the power consumption to leave the rack running at night.  I can stay an extra hour or so at work after hours to study quietly and access the rack from work.

Either way, I AM going to go for the NP.  I’m spending the next week or so going back through my written notes, watching videos again, and reading chapters in the BSCI book over the next week or so.  I bought the BSCI Lab Portfolio a month or so ago, so I’ll spend the next week going through those labs at night.

The physical topology for the bulk of the labs has four routers and one switch.

These are the routers and switch that I’ve added to the mix.  At some point, I know the lab guide will add the frame switch and possibly another router.  I need to pick up a few extra WIC-1T cards soon.

I made it through the first few EIGRP labs, tonight.  The objectives were pretty basic…

1.  Configure EIGRP on an interface.  simple

r1# configure terminal

r1(config)# int eth fa 0/0

r1(config-if)# ip addr 10.1.100.1 255.255.255.0

r1(config-if)# router eigrp 1

r1(config-router)# network 10.0.0.0

2.  Configure the bandwidth command to limit EIGRP bandwidth

r1(config-if)# bandwidth 64 ! bandwidth in kbps

3.  Verify EIGRP adjacencies

r1# show ip eigrp neighbors

or the alternative and more verbose

r1# show ip eigrp neighbors detail

4.  Utilize debugging commands for troubleshooting EIGRP

r1#  debug eigrp packets ! don’t forget to issue no debug all afterwords.

5.  Challenge:  test convergence for EIGRP when a topology change occurs.

This one was kinda weird.  The preferred path from R3 to a loopback on R1 is going to be via fast ethernet.  The lab has you ping from R3 to lo 3 on R1 with 100,000 pings(this is done using the ping $ip repeat 100000 command).  During these pings, you are to kill R1’s FA interface.  We haven’t modified the variance in EIGRP, and the AD through R2’s serial interface to R1 is more than the FD to lo 3, so the route doesn’t exist in the topology table.

When we killed FA 0/0 on R1, we obviously lost six pings while EIGRP discovered the new route through R2.  What confused me, was when I brought FA 0/0 back up on R1, we lost 33 or 34 pings while while the route through R1’s FA port came back up.

I’ll make it through the remaining EIGRP labs tomorrow night, and hopefully I’ll get through the OSPF labs.  I know there is going to be some slight re-cabling to bring the frame switch back into the mix.  I just hope I have enough WIC-1T interfaces to cover the physical topology change.

More Trainsignal

I made it through all four of the trainsignal OSPF videos from Trainsignal. I will say that I am completely impressed by Chris Bryant’s teaching and have been very happy with the products so far. My only issue has been the brief explanation he gave on stub areas/NSSA. I found his explanations of NSSA, specifically, to be a little confusing. I’m familiar with how they work and have set them up in lab scenarios, so I’m not concerned for myself… I just thought a little more time could have been spent on them. Maybe he’ll get to it a little more in depth with redistribution.

I don’t have much going on today. We’re doing some work at a remote site this evening, so we’ve been pretty relaxed today. I decided to start the BGP videos, since that’s one of the areas I’m lacking. Just as a side note… I really need to get a better PC to load dynamips on. I have a great rack at home, but I can’t afford to leave it running 24/7 (power consumption). It’d be nice to be able to load a few 2600’s on my work PC, but dynamips keeps crashing. I have a P4 1.8 with 1.5 gigs of RAM, and everytime I load a pair of 2621XM’s (for IOS 12.4), the damned server crashes.

Anyway… Some of the key points from the first hour of the BGP video were:
1. Two classes of attributes: well known and optional. (He didn’t go any further than this just yet.)
2. BGP uses TCP port 179 for communication and uses keep alives to maintain connection.
3. Full tables are exchanged during the relationship establishment. Following that, updates are only sent when a change occurs.
4. Cisco recommends that eBGP peers are directly connected, though there wasn’t any mention of whether or not this is REQUIRED. iBGP peers to not need to be directly connected.
5. BGP states:
a. idle
b. connect
c. active
d. opensent
e. openconfirm
f. established (this is what you want to see when running show ip bgp neighbor and show ip bgp summary)

ebgp_multihop.jpg
A Sample configuration for the above:

R1#conf t
R1(config)#router bgp 100
R1(config-router)#neighbor 172.12.123.3 remote-as 200

R3#conf t
R3(config)#router bgp 200
R3(config-router)#neighbor 172.12.123.1 remote-as 100

If we wanted to use loopback interfaces for additional stability (this would come into play for iBGP with multiple paths to each host, and eBGP with two direct links between peers), we would use the following:
R1#conf t
R1(config)#router bgp 100
R1(config-router)#neighbor 3.3.3.3 remote-as 200
R1(config-router)#neighbor 3.3.3.3 ebgp-multihop 2
(we use the multihop command because we are not peering with the IP address directly connected to us.  The 2 is the number of hops we need to traverse)
R1(config-router)#neighbor 3.3.3.3 update-source lo0 (this is telling the local router to use lo0 as the source of all bgp traffic.  No matter what interface we use to communicate with 3.3.3.3, we will use that Lo as the source IP. )

One of the gotchas was to make sure that we had routes to the loopback interfaces on each side. Since we’re not running an IGP between the two, we opted to use static routes. In Chris’s video, R1 and R3 were connected through a frame switch. He used the interface option in his static route, and the adjacency never came up. When he changed the static route to use the next hop, it came up.

Chris also went through some basic network information in BGP.
First and foremost, when you advertise a network in BGP, you must use the EXACT mask that you have setup or that exists in your routing table. EX:
R1#conf t
R1(config)#interface lo1
R1(config-if)#ip addr 11.11.11.11 255.255.255.255

would require the following network statement in BGP:
R1(config-router)#network 11.11.11.11 mask 255.255.255.255

whereas
R1#conf t
R1(config)#interface lo1
R1(config-if)#ip addr 11.11.11.11 255.255.255.0

would require this statement:
R1(config-router)#network 11.11.11.0 mask 255.255.255.0
The command show ip bgp on the local router will tell you if the route is being advertised to it’s peers.

I want to make it through the rest of the BGP sections and IPv6 before Saturday so I can spend the day working on these labs. My wife will be at another baby shower, and is taking the rugrat with her. I’m determined to get this exam done by Friday of next week.

trainsignal/lack of sleep

Alex Skinger from Trainsignal contacted me last week, and asked if I would be interested in checking out the BSCI/BCMSN/CCNA training materials from them. Until this point, I’ve been relying solely on Cisco Press books and reading things on the internet. I figured I’d give the VBT a try and see how I like it.

The materials showed up today, and were waiting for me when I got home from work this evening. I immediately tore through the packaging and threw the BSCI stuff into the laptop. So far, I’ve made it through the IP routing fundamentals video (just over an hour), the distance vector protocols video (somewhere in the range of 40 minutes), and the intro to OSPF video (about an hour). I have to say, I’m impressed. Chris Bryant covered some information in the DHCP server and ip helper configurations that I haven’t seen covered in three different versions of BSCN/BSCI Cisco Press books, AND the Network Academy curriculum. He’s also covered some additional details and key points in RIPv2 and OSPF that weren’t covered in the current study guides. I don’t know if that info will be on the test, but it’s good stuff to know.

I started working on the practice exams tonight, and I’m severely lacking in BGP and IPv6. I wanted to take the exam by next Friday. I’m starting to wonder if that’s enough time, or if I should postpone for a week. I guess we’ll see how my study schedule pans out for the rest of this week and weekend. I’m still fighting this flu/stomach shit that I’ve got. I’ve felt completely drained all week. By the time my lunch hour rolls around at work, I feel like I haven’t slept in days, and completely exhausted. That makes it pretty difficult to focus and study at all in the afternoons and evenings when I get home. I may just need to take a night and sleep.

Progress

I’ve been studying off and on for BSCI all year.  I was hoping to have the exam out of the way by August, and never got there.  While working at Option One Mortgage’s DR facility, I spent most of the days trying to study and playing freecell.  Here I am in November and I still haven’t taken the exam. 

I did hit a milestone last night.  I finished the Third Edition Self-Study Guide from Cisco Press.  I haven’t been doing a whole lot of labs, as my lab hardware has been sitting in a friend’s dining room.  I spend about 5 hours a week at his place working on his CCNA.  I may need to pick my rack up this week so I can start running through the labs. 

I understand the topics pretty well.  I can look at configs, understand what’s going on, and why things are the way they are.  My issue with all of the practice tests has been configuration snipets here and there. 

I finish up with my Bachelor of Science Program at UofP next week, so that’ll give me a bit more time each week to study.  I’m going to run through the self-study guide one more time in the next month as well as the Exam Certification Guide and take the exam by the end of December.

I’m already pretty comfortable with EIGRP concepts and functionality because my previous two jobs were EIGRP shops.  I’m struggling with OSPF LSA types and the modes of operation for each layer 2 technology.  I’ve taken pretty thorough notes on it.  I just need to study them.

I need to go back and take better notes on IS-IS, route redistribution, BGP, and multicast.  I think I can handle that in a month.

eigrp-notes.doc