What is IT?

Cisco Data Center Fabric -- An Overview- Cisco VP Soni Jiandani

2011-11-30T20:03:00.000-08:00

Silvano Gai: Nexus UCS

2011-11-22T03:46:00.000-08:00

Fulcrum's Formula

2011-11-20T04:09:00.000-08:00

Fulcrum Microsystems is proud of its FM4000 family of switches which come in a variety of port configurations and package sizes that are tailored for key applications ranging from server clustering to port aggregation. But I am interested in talking about its FM4224 model which provides ultra low latency switching. To understand how Fulcrum does this we need to understand the two very common Ethernet switching paradigms first: cut-through and store-and-forward.

Both Store-and-forward and Cut-through switches follow the same forwarding decision process which is based on the destination MAC address of data packets. It is the series of steps in which they do this forwarding decision that differentiates the both processes. Ideally store-and-forward switch makes a forwarding decision on a data packet after it has received the whole frame and checked its integrity, a cut-through switch engages in the forwarding process soon after it has examined the destination MAC (DMAC) address of an incoming frame. The DMAC address is found in the first 6 bytes of a frame so as per above definition a cut-through switch should screen only those first 6 bytes but in practise they wait until a few more bytes of the frame have been checked before they make any decision.

Let’s look at cut-through switching in more detail. When a cut-through switch receives and invalid or bad packet it does not drop the packet like a store-and-forward switch but the best it can do is flag it and send it. So all the invalid packets are sent to the other segments of the network where the frame is examined and dropped by the destination switch. So to make a more intelligent decision cut-through switches examine more than just the DMAC bytes when a packet comes in. And the more interesting thing is that the number of bytes the switch is going to read can be predetermined based on the value of the EtherType field. For more information on the EtherType field of a frame please visit http://en.wikipedia.org/wiki/EtherType .

So what’s the major advantage of the cut-through switches over store-and-forward switches? Well you have guessed it right. It’s the speed at which they forward the packets. And for some high performance applications where latencies are very critical cut-through switches dominate over the store-and-forward switches. But cut-through switches are not all that great. They have some drawbacks too. Check out the link which shows a presentation from Fulcrum’s website. The presentation compares different switching paradigms and their drawbacks.The comparision is based on the memory architechture.

But my question is what is fulcrum's formula? If you checked the above link you will see that Fulcrum uses RapidArray memory and Nexus crossbar to improve it buffer speed. So Nexus is a highly efficient fully-connected non-blocking crossbar circuit, providing the highest capacity of over a Terabit in TSMC’s 130nm FSG process technology, the lowest latency of less than 3ns, the smallest die area and the most efficient power profile where power consumption is directly related to activity. Nexus has been fabricated and fully characterized in process technologies ranging from 0.25um to 65nm. It is being leveraged by Fulcrum in its latest generation switch products, and licensed to partners as an efficient on-chip interconnect infrastructure.

Fulcrum has designed its own SRAM and TCAM technology, to deliver sophisticated multi-ported SRAM blocks that operate at more than twice the speed of standard ASIC-based memories, and consume less power (only when active). The circuit complements Nexus in switch systems where fast memory and efficient switching go hand-in-hand. Similar to Nexus, RapidArray has been fabricated and fully characterized in various process nodes and block sizes, the largest to date being well over 9MB of SRAM and 500KB of TCAM in the TSMC 65nm process.

Together as shown in the above diagram Fulcrum provides single shared memory for highly efficient cut-through switching.

GLBP caught up in the Broadcast Storm

2011-10-30T06:12:00.000-07:00

We all know that broadcast storms can degrade network performance. I have seen one such case last week. A Unix guy complained that his server was losing connections. He showed logs from his server. There were flaps on his nics. The server is connected in a U shaped network which means he has two NICs in bonding and each of them is connected to a diffrent switch. I didn't find any issues on the access layer swithes. There were no logs, no errors on the interfaces, no CPU utilization, nothing! I logged into the gateway 6500 switches and found GLBP flaps for that particular VLAN. I checked the tracking interface which was fine. No other logs on the devices other than the continuous GLBP flaps. There were several vlan interfaces in there and the GLBP for them were fine. The issue resolved on its own( luckily). Later when I pulled SevOne report for that particular interface there was a high rise in the broadcast traffic on that VLAN and this was causing the issue. So how is the broadcast storm affecting GLBP? I guess the stom blocked/delayed the hello packets of GLBP causing continous failovers. Let me know if you have any thoughts on this

Optera Training

2011-10-18T22:37:00.000-07:00

1. Things that you should know:
=======================
a. DWDM: DWDM (Dense Wave Division Multiplexing) allows multiple light waves to travel on the same optical fiber, thereby considerably increasing its capacity. Different types of traffic can be assigned to each wavelength.
More info on DWDM can be found on wiki
b. Fiber Types: There are basically two types of optical fiber: Multi-mode and Single Mode. While Multi-Mode can be either step-index or graded-index, most modern multi-mode fibers types today are graded-index.
c. Connector types: There are four types of connectors commonly in use today:
FC - Commonly used on OCLD cards. These are keyed connectors with a screw-on head. Make sure the key is inserted before the connector is screwed on.
MU – Also referred as “little” connectors. Used on cards where space is an issue. Used on multi-port SRM cards to connect cards to the distribution panel.
SC – Common OC3 fiber connector. It is a keyed connected. Used on Passport OC3 card, Optera OCI cards and Cisco routers.
ST –Twist-lock type connector. Not very common.

d. Site types: There are three types of sites: Terminal, OADM and OFA

A Terminal site is a terminating site. Band and channels terminate at the Terminal site and they do not pass through. Terminal sites are implemented by wiring in the OMX module.

In an OADM (Optical Add-Drop Multiplexer) some band are dropped while some other bands are allowed to pass-through. OADM sites are implemented by wiring in the OMX module.

An OFA (Optical Fiber Amplifier) site is made up of a 5200 shelf that contains C and L amplifiers. The OFA site is required whenever the signal needs to be boosted. Note that an OFA shelf can be co-located with OADM sites.

2. Lets check the hardware:
====================

There are 20 slots in a 5200 shelf. In R3, the position of each card is fixed.
The shelf is divided in a West (cards 1-4) and East section (cards 15-18). The OCLDs in the East section of one shelf connect to the OCLDs in the West section of the next shelf in the network.

The cards are:

OCI circuit pack: The optical-channel interface (OCI) circuit packs provide an interface between subtending equipment and the OPTera Metro 5200 system. You can install a maximum of eight OCI circuit packs in an OPTera Metro 5200 shelf. Some OCI circuit packs are designed to support only particular protocols.

OCLD circuit pack: Optical channel laser and detector (OCLD) circuit packs are identified by wavelength band (BAND 1 to BAND 8) and by channel within the wavelength band (CH1 to CH4). Channels of the OCLD circuit packs relate to the wavelength band of the OMX modules in the shelf. Specific channels of OCLD circuit packs have fixed positions in the OPTera Metro 5200 shelf. Up to eight OCLD circuit packs can be installed in the shelf.

OCM circuit pack: The optical channel manager (OCM) circuit pack bridges the data channel between the OCLD and OCI circuit packs.

SP circuit pack: The shelf processor (SP) circuit pack manages communication functions for OPTera Metro 5200. There is one SP circuit pack in an OPTera Metro 5200 shelf.

Filler cards: Filler cards are installed in slots of the OPTera Metro 5200 shelf that do not have active circuit packs.
There are three types of filler cards:
• OCLD filler cards
• OFA filler cards
• blank filler cards

OMX modules
Each OPTera Metro 5200 OADM or terminal shelf has an optical multiplexer (OMX) tray that holds two OMX modules. Each OMX module has one wavelength band filter, and one channel filter. The OMX wavelength band must be the same for both OMX modules installed in the same shelf. The OMX wavelength band also determines the wavelengths of the optical channel laser and detector (OCLD) cards that you install in the shelf.
Each OMX module contains passive optical filters that add and drop up to four channels in the wavelength band assigned to the OPTera Metro 5200 shelf.
Other channels pass through the OMX unchanged.
The OMX module in OPTera Metro 5200 has two functional areas:
• optical add section
• optical drop section
The optical add section contains a band filter (ADF) and a channel multiplexer (MUX). The optical drop section contains a band filter and a channel demultiplexer (DEMUX). The ADF drops specific wavelengths while allowing other wavelengths to pass through the filter.

Signal Flow: Let's follow the signal
==========================

OCLD
–The client connects to an OCI circuit pack at 1350Nm or 850Nm this card transforms the signal
from optical to electrical and passes it across the chassis backplane (via the OCM) to an OCLD.
–The OCLD then transforms the electrical signal to a WDM wavelength. and passes it externally
(via a fiber patch) to the OMX.
–The OMX then Multiplex's this WDM wavelength into a channel of four, then adds them to a single
fiber cable carrying another three possible Channels.

OTR/MOTR
–The client connects to the OTR/MOTR at 1350Nm or 850Nm the card then transforms this signal
to a single WDM wavelength(with out using the chassis back or management) in the case of the
MOTR multiple signals are time division multiplexed into the single output signal this is then
passed externally (via a fiber patch) to the OMX.

–The OXM then Multiplex's this WDM wavelength into a channel of four, then adds them to a
single fiber cable carrying another three possible Channels

Beej’s Guide to Network Programming

2011-10-09T19:41:00.000-07:00

A friend recommended this book. It is simple and good

Socket Programming

2011-10-03T00:02:00.000-07:00

Although I hate programming so much I find socket programming quite interesting. I recommend Beej’s Guide to Network Programming. It's a fun way to start if you are scared of programming like I am.

Wireless Sensor Networks: Technology and Applications

2011-09-17T02:29:00.000-07:00

Future of Wireless Sensor Networks

2011-09-17T02:20:00.000-07:00

My TSHOOT Exam!

2011-09-07T04:52:00.000-07:00

I was surprised by the format.. I expected the format to be like the ROUTE and SWITCH exam with good proportion of all types of question. But when the exam started the exam instruction said that there will be 4 questions and pass marks is 790! I read it twice and clicked next. The first 3 questions were multiple choice questions and the fourth one was a topology based question with 14 trouble tickets in it. The exam was brilliant. It was so much fun solving those trouble tickets. Absolutely scary too because I was running out of time. But it was great experience. The TSHOOT exam rocks..

CCNP Accomplished!!

2011-09-06T09:33:00.000-07:00

Everyone, I finished my CCNP TSHOOT exam today and with it I have I have finished all 3 exams for CCNP! I will get my certification kit soon. Can't stop laying hands on it. Will update a blog soon about the TSHOOT exam. It was the best exam I ever took!

Things that you might miss when studying HSRP

2011-08-09T12:16:00.000-07:00

HSRP group can contain more than two members; One is active member, one is standby router and the others will be in listening HSRP state.
HSRP sends hello messages to 224.0.0.2 (All Routers Multicast Address) using UDP port 1985.
HSRP group numbers can be [0,255]
HSRP groups are locally significant on the interface. This is very important point to understand. For example, HSRP group 1 on the VLAN 10 interface is not same as the HSRP group 20 on VLAN 11 interface.
HSRP router election:

Default priority is 100
Active Router is the one with the highest priority

If there is a priority tie then the router with the highest HSRP Ip address wins.

6. HSRP States: Disabled> Init> Listen> Speak> Standby> Active.

7. Only standby member monitors the hello messages. Listening members do not monitor them.

8. Default hello message every =3s; Hold time=10s
9. The actual interface address and the standby address must be configured to be in the same IP subnet.

Understanding your NetFlow

2011-07-17T23:44:00.000-07:00

I was using SevOne at office the other day to pull some reports of the nonunicast traffic in a vlan to troubleshoot a particular GLBP issue. And then I wondered what will I do without such tools. Then I became curious and wanted to know how it actually knows all that information.
SevOne consolidates granular performance data from various data sources such as SNMP, NetFlow, VoIP, IP SLA, NBAR and WMI onto a unified dashboard. I want to particularly focus on NetFlow in this paticular article.

Netflow is a network protocol that was developed by Cisco in 1996. It was designed to collect IP traffic information. Soon it became an industry standard for traffic monitoring. There has been several versions of Netflow developed over the years and its current state is known in the industry as Flexible NetFlow.

The flow is defined by factors such as Source IP address, Destination IP address, Source port, Destination Port, Layer 3 protocol type. The version5 which is the most common version in use has 18 such fields. Version 5 is great if you are just looking for regular IPv4 traffic. It does not provide in depth analysis of the traffic but provides a very good overview of the composition of your traffic flow. The Later versions such as v7 and v8 were extensions of v5 and had features like router-based aggregation and reduced NetFlow export data volume.

The problem with these versions was that they used fixed export formats that were not flexible and adaptable. This caused the customers to re-engineer for each new version. So they built a more flexible and extensible export format called version 9. This was done by introducing the notion of template. Templates provide an extensible design to the record format, a feature that should allow future enhancements to NetFlow services without requiring concurrent changes to the basic flow-record format. This new feature supports additional technologies such as MPLS or Multicast.

We also have Internet Protocol Flow Information Export (IPFIX) coming up in the near future which is based on NetFlow Version 9 but acts as a more universal industry standard.

Partial Picture of Internet

2011-07-07T10:18:00.001-07:00

EIGRP Stub

2011-06-04T07:17:00.000-07:00

When using the EIGRP Stub Routing feature, you need to configure the distribution and remote routers to use EIGRP, and to configure only the remote router as a stub. Only specified routes are propagated from the remote (stub) router. The router responds to queries for summaries, connected routes, redistributed static routes, external routes, and internal routes with the message "inaccessible." A router that is configured as a stub will send a special peer information packet to all neighboring routers to report its status as a stub router.

Any neighbor that receives a packet informing it of the stub status will not query the stub router for any routes, and a router that has a stub peer will not query that peer. The stub router will depend on the distribution router to send the proper updates to all peers.

Passive Interface in EIGRP and OSPF

2011-06-01T06:19:00.000-07:00

As an extention to the previous lab we also configure OSPF in the above network. So we have both EIGRP and OSPF on both the routers. In order for the routers to choose OSPF over EIGRP we reduce the AD of OSPF from 110 to 5.

Tip: Configure the loopbacks under OSPF point-to-point network. Otherwise OSPF will make them a /32 network no matter what the actual subnet is.

Now we will check the effect of passive-interface command in OSPF.
1. Enable wireshark capture on R3 fa0/0. Also turn on debug commands on routers.
2. Make fa0/0 on R2 a OSPF passive-interface
3. OSPF drops off and EIGRP kicks in.

*Mar 1 13:39:58.352: %OSPF-5-ADJCHG: Process 1, Nbr 120.120.120.120 on FastEthernet0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
R2#
*Mar 1 13:39:59.788: %SYS-5-CONFIG_I: Configured from console by console
R2#
*Mar 1 13:40:03.868: IP-EIGRP(Default-IP-Routing-Table:1): route installed for 110.110.110.0 ()
*Mar 1 13:40:03.872: IP-EIGRP(Default-IP-Routing-Table:1): route installed for 120.120.120.0 ()
*Mar 1 13:40:03.872: IP-EIGRP(Default-IP-Routing-Table:1): route installed for 100.100.100.100 ()
Sh ip route output before:
Gateway of last resort is not set

     100.0.0.0/32 is subnetted, 1 subnets
O IA    100.100.100.100 [5/11] via 23.23.23.2, 00:00:06, FastEthernet0/0
     33.0.0.0/24 is subnetted, 1 subnets
C       33.33.33.0 is directly connected, Loopback3
     23.0.0.0/30 is subnetted, 1 subnets
C       23.23.23.0 is directly connected, FastEthernet0/0
     22.0.0.0/24 is subnetted, 1 subnets
C       22.22.22.0 is directly connected, Loopback2
     110.0.0.0/24 is subnetted, 1 subnets
O IA    110.110.110.0 [5/11] via 23.23.23.2, 00:00:06, FastEthernet0/0
     10.0.0.0/24 is subnetted, 1 subnets
C       10.10.10.0 is directly connected, Loopback0
     11.0.0.0/24 is subnetted, 1 subnets
C       11.11.11.0 is directly connected, Loopback1
     120.0.0.0/24 is subnetted, 1 subnets
O IA    120.120.120.0 [5/11] via 23.23.23.2, 00:00:08, FastEthernet0/0

Sh ip route output after:

Gateway of last resort is not set

     100.0.0.0/32 is subnetted, 1 subnets
D       100.100.100.100 [90/409600] via 23.23.23.2, 00:02:21, FastEthernet0/0
     33.0.0.0/24 is subnetted, 1 subnets
C       33.33.33.0 is directly connected, Loopback3
     23.0.0.0/30 is subnetted, 1 subnets
C       23.23.23.0 is directly connected, FastEthernet0/0
     22.0.0.0/24 is subnetted, 1 subnets
C       22.22.22.0 is directly connected, Loopback2
     110.0.0.0/24 is subnetted, 1 subnets
D       110.110.110.0 [90/409600] via 23.23.23.2, 00:02:21, FastEthernet0/0
     10.0.0.0/24 is subnetted, 1 subnets
C       10.10.10.0 is directly connected, Loopback0
     11.0.0.0/24 is subnetted, 1 subnets
C       11.11.11.0 is directly connected, Loopback1
     120.0.0.0/24 is subnetted, 1 subnets
D       120.120.120.0 [90/409600] via 23.23.23.2, 00:02:22, FastEthernet0/0

R3 fa0/0 is still receiving hello packets fro R3 fa0/0.. Since R3 is the DR router but there is no response from the other end..

Passive Interface in EIGRP

2011-05-31T08:13:00.000-07:00

In EIGRP the passive-interface command stops sending outgoing hello packets, hence the router can not form any neighbor relationship via the passive interface. This behavior stops both outgoing and incoming routing updates.

Config:
======
R3#    sh ip int br
Interface                  IP-Address      OK? Method Status                Protocol
FastEthernet0/0            23.23.23.2      YES manual up                    up
FastEthernet0/1            unassigned      YES unset administratively down down
Loopback0                  100.100.100.100 YES manual up                    up
Loopback1                  110.110.110.110 YES manual up                    up
Loopback2                  120.120.120.120 YES manual up                    up

R2#sh ip int br
Interface                  IP-Address      OK? Method Status                Protocol
FastEthernet0/0            23.23.23.1      YES manual up                    up
FastEthernet0/1            unassigned      YES unset administratively down down
Loopback0                  10.10.10.10     YES manual up                    up
Loopback1                  11.11.11.11     YES manual up                    up
Loopback2                  22.22.22.22     YES manual up                    up
Loopback3                  33.33.33.33     YES manual up                    up

We have loopback interfaces on R3 and R2 to make it look like we have networks connected to the routers. We also disable auto summarization on both R2 and R3 to make it look like the loopback interfaces are connected to the bove networks.

Now we make fa0/0 on R2 passive interface and capture the traffic on fa0/0 on R3.

R2(config)#router eigrp 1
R2(config-router)#passive-interface fa0/0
R2(config-router)#
*Mar 1 02:27:15.183: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 1: Neighbor 23.23.23.2 (FastEthernet0/0) is down: interface passive
R2(config-router)#^Z
R2#

Here is the output from the wireshark:

You will notice that as soon as we make fa0/0 on R2 a passive interface it stops sending hello packets.
The adjecency drops immediately. It doesn't wait for hold time to expire.

Policy Based Routing Troubles

2011-05-26T06:03:00.000-07:00

Objective:
=========
1. All http traffic from R2 to R5 should go through R1
2. All telnet traffic from R2 to R5 should go through R3
3. Rest of the traffic should loadbalance between R1 and R3.

Config:
=====
On R2
R2#sh access-lists
Extended IP access list TELNET
    10 permit 23 any 45.45.45.0 0.0.0.255
R2#sh route-map
route-map PBR, permit, sequence 10
Match clauses:
    ip address (access-lists): TELNET
Set clauses:
    ip next-hop 23.23.23.2
Policy routing matches: 0 packets, 0 bytes
!
interface Serial0/0
description R2 to R1
ip address 12.12.12.2 255.255.255.252
ip policy route-map PBR
clock rate 2000000
end
!
interface Serial0/1
description R2 to R3
ip address 23.23.23.1 255.255.255.252
ip policy route-map PBR
shutdown
clock rate 2000000
end

Problem:
======

When I telnet from R2 to R5 it connects. Then to test the route map I shut the se1/0 on R2 which goes to R3. So as per the policy the telnet should not work as the next hop is disabled but I am still able to telnet!! See output below:

R2(config)#do telnet 45.45.45.2
Trying 45.45.45.2 ... Open

User Access Verification

Password:
R5>exit

[Connection to 45.45.45.2 closed by foreign host]
R2(config)#int se1/0
R2(config-if)#shut           ! I have shut the port!
R2(config-if)#do telnet 45.45.45.2
Trying 45.45.45.2 ... Open

User Access Verification

Password:
R5>exit               ! It still connect!!!!

[Connection to 45.45.45.2 closed by foreign host]

EIGRP Lab: Redistribution, Route-maps and Tagging

2011-05-23T16:11:00.000-07:00

Overview:
========
This lab is an extension fo the previous lab, EIGRP over frame-relay. In this lab I added R4 to the topology and configured the R4<>R1 link in EIGRP AS1. I also created loopbacks on R4 and advertised them into EIGRP AS2.
Objective:
=========
1. Redistribute EIGRP AS1 routes into EIGRP AS2 routes( Simple)
2. Use route map to redistribute loopback routes into EIGRP AS1 and tag the /24 or lesser subnets with 2000.
Config:
======
R1#sh run int se0/1
Building configuration...
Current configuration : 86 bytes
!
interface Serial0/1
ip address 14.14.14.2 255.255.255.252
clock rate 2000000
end
!
R4#sh run int se0/0
Building configuration...
Current configuration : 86 bytes
!
interface Serial0/0
ip address 14.14.14.1 255.255.255.252
clock rate 2000000
end
!
router eigrp 1
redistribute eigrp 2 route-map AS2TOAS1
network 14.14.14.0 0.0.0.255
default-metric 100 100 100 100 100
no auto-summary
router eigrp 2
redistribute eigrp 1 metric 100 100 100 100 100
network 40.0.0.0
no auto-summary

R4#sh route-map
route-map AS2TOAS1, permit, sequence 10
Match clauses:
    ip address prefix-lists: LOW
Set clauses:
    tag 2000
Policy routing matches: 0 packets, 0 bytes
route-map AS2TOAS1, permit, sequence 20
Match clauses:
Set clauses:
Policy routing matches: 0 packets, 0 bytes

R4#             sh ip prefix-list det
Prefix-list with the last deletion/insertion: LOW
ip prefix-list LOW:
   count: 1, range entries: 1, sequences: 5 - 5, refcount: 3
   seq 5 permit 40.0.0.0/8 le 24 (hit count: 6, refcount: 1)

EIGRP over frame-relay

2011-05-22T23:32:00.000-07:00

Story:
=====
The basic idea of this lab was to create a frame relay network using EIGRP. We have three routers R1, R2 and R3 connected to a frame relay switch. R1 is the hub.

I felt that the lab will be easy but I am going wrong somewhere. I created the frame relay network and configured EIGRP over it and I am able to ping one spoke router from another spoke router. But then I created loopbacks on R2 and advertised them using EIGRP but R1 is not learning those addresses.

Config:

On R1:
======
!
interface Serial0/0
ip address 10.10.10.10 255.255.255.0
encapsulation frame-relay
no ip split-horizon eigrp 1
clock rate 2000000
frame-relay map ip 10.10.10.10 101
frame-relay map ip 10.10.10.30 101 broadcast
frame-relay map ip 10.10.10.20 102 broadcast
no frame-relay inverse-arp
end
!
R1#sh run | sec eigrp
no ip split-horizon eigrp 1
router eigrp 1
network 0.0.0.0
no auto-summary
R1#

On R2:
======
!
interface Serial0/0
ip address 10.10.10.20 255.255.255.0
encapsulation frame-relay
clock rate 2000000
frame-relay map ip 10.10.10.20 203
frame-relay map ip 10.10.10.30 203
frame-relay map ip 10.10.10.10 203
no frame-relay inverse-arp
end
!
R2#sh run | sec eigrp
router eigrp 1
network 0.0.0.0
no auto-summary
R2#

On R3:
======
!
interface Serial0/0
ip address 10.10.10.30 255.255.255.0
encapsulation frame-relay
clock rate 2000000
frame-relay map ip 10.10.10.30 202
frame-relay map ip 10.10.10.20 202
frame-relay map ip 10.10.10.10 202
no frame-relay inverse-arp
end
!
R3#sh run | sec eigrp
router eigrp 1
network 0.0.0.0
no auto-summary
R3#

OSPF Lab1

2011-05-14T08:00:00.000-07:00

Click on the diagram to enlarge

Overview: I created this lab today for basic OSPF concepts.
Objectives:
1. Create POINT_TO_POINT OSPF on the link between R1 and R2.
2. Create loopback interfaces on R1 and advertise them into area 1. Configure the loopbacks to reflect networks subnets( this can be done by configuring the ospf network under these loopsbacks as POINT_TO_POINT links)
3. Create a BROADCAST network between R2, R3 and R4 and put it under area2
4. Create a loopback on R3 and configure it in area2 (easy one).
5. Create a loopback on R4 and configure it in area3. Try to ping lo on R3 and lo on R4 from R1. Ping to lo of R4 fails.
6. Create a virtual link between R4 and R2 over trasit area2. Perfom ping test mentioned above again.
The ping to lo on R4 from R1 should be successful.

Verification:
sh ip route
sh ip ospf
sh ip ospf nei
sh ip ospf adj
sh ip ospf route
sh ip ospf database
debug ip ospf packet
debug ip ospf adj

Also use wireshark to learn about the LSA types. You will mostly see LSA1 and LSA2s in this lab.

My Bicycle Ride on CCNP ROUTE

2011-04-24T21:49:00.000-07:00

I was never interested in taking CCNP before because you have to take so many brutally tough exams to get certified. So after my CCNA I completed JNCIA-FWV and ITIL V3 certifications. Well I always believed that diversity in learning technologies helps. But the new CCNP which was revised last year is so irresistible. It gives so much emphasis on planning and reviewing a network design that I decided that I should take it. It also lays perfect foundation for CCIE!

As I was very comfortable with the syllabus of CCNP Switch I decided to complete the tougher CCNP Route first. I bought the official guide from the book market in Koti for 350rs I think. The guy at the store was an ..... Well I will just say that he was not so kind guy and that he didn't give me any discount to avoid using inappropriate language. The book is so amazingly filled with details that it hurt my brains when I read it the first time. It took me three days to complete casually reading the EIGRP part. Then I got Jeremy Cioara's CBT Nuggets and that made my life so much simple. I converted the videos into MP4 format and uploaded them on my cell phone. I play them almost everyday on my way to office- although I can't concentrate that much. I also bought CCNP ROUTE Portable Command Guide. It's an amazing book if you already know the concepts. It is so fast to read and the configurations cover all the steps, which is a boon. But finally the most important preparation tool is my GNS3. I have no words to explain how cool it is. You have to use it to admire its AWESOMENESS! And it is free- There is still humanity in this world!

So guys I have my exam booked on 11th of May which is 16 days from today and I am already so confident that I will easily clear the exam. I will update you, guys once it is done. Please leave your comments and questions below.