NDP – Neighbor Discovery Protocol: IPv6 Stateless address autoconfiguration SLAAC

How does the internet work - We know what is networking

IPv6 Neighbor Discovery Protocol It’s the way the IPv6 hosts learn the addresses as well as about the neighbors around himself. That includes learning about other hosts and routers on local network. That is the biggest difference between IPv4 and IPv6. The Neighbor Discovery Protocol is also called ND or NDP, makes this and other […]

NDP – Neighbor Discovery Protocol: IPv6 Stateless address autoconfiguration SLAAC

2012 in review

The WordPress.com stats helper monkeys prepared a 2012 annual report for this blog.

Here’s an excerpt:

The new Boeing 787 Dreamliner can carry about 250 passengers. This blog was viewed about 1,100 times in 2012. If it were a Dreamliner, it would take about 4 trips to carry that many people.

Click here to see the complete report.


Quiz #2 &#8211 OSPF Redistribution between different processes

Redistribution between different or same routing protocols can become a nasty thing when there are 2 or more redistribution points.
In this quiz, redistribution is configured between 2 different OSPF processes on 2 routers. Without a proper configuration, this can lead to routing loops. Read the quiz to see the loop in action and try to solve it.

Upgrading ESXi Hypervisor to 5.1

Ahh the Christmas break. The perfect time for good food, enjoying the company of family and friends and of course…. IT projects at home! My project last year was to immerse myself in the source code for OpenBSD's snmp daemon so that I could integrate my patch-set for Net-SNMP directly into the native OpenBSD daemon. That was time well spent as I was able to integrate my code in the following weeks. This year I have maintenance to do in the home lab. It looks like 2013 is going to be a busy year as far as getting my hands on new stuff so I want the lab ready to rock.

First project: upgrade my VMware ESXi server from 4.1 to 5.1.

PNRP Name Resolution – How it works?

How does the internet work - We know what is networking

PNRP name resolution protocol uses this two steps: Endpoint determination – In this step the peer is determining the IPv6 address of the computer network card on which the PNRP ID service is published. PNRP ID resolution – After locating and testing the reachability of the peer with the PNRP ID with desired PNRP service, […]

PNRP Name Resolution – How it works?

PNRP the New DNS – Peer Name Resolution Protocol

How does the internet work - We know what is networking

PNRP – The Peer Name Resolution Protocol is new protocol made by Microsoft which is one of the first technology that will change the way we think about naming resolution in computer networking and possibly be the next DNS – Domain Name System like technology. PNRP is the new DNS but there are so much […]

PNRP the New DNS – Peer Name Resolution Protocol

Quiz #1 &#8211 MSTP

This is my first quiz and I chose an MSTP misconfiguration scenario that could be easily overlooked on the first encounter.
A fiber got cut revealed some hidden MSTP implementation problems. It was enough for one link to go down and the connectivity got impacted in a network that was supposed to be redundant. Read along and try to spot the problem.

Quick-n-dirty ‘network’ statement generator

I recently had a requirement to feed a lab router a bunch of BGP prefixes for some testing. The test required a non-overlapping, random-looking population of prefixes from several different eBGP neighbors.

I decided to bang together a little script to generate the prefixes in a format suitable for quagga's bgpd daemon, but wound up adding features throughout the day as I discovered new requirements. The end result was something that might be useful to somebody else.

Here I'm telling it to give me 5 network statements from within 10.0.0.0/8. The netmask will be 24 bits:
$ ./bgpdgen.pl -c 5 -n 10.0.0.0/8 -m 24
 network 10.160.244.0/24
 network 10.61.69.0/24
 network 10.13.1.0/24
 network 10.13.138.0/24
 network 10.50.109.0/24
Or I can have a range of bitmasks, this time the networks are packed much tighter and they'll be masked with 26 to 30 bits:
$ ./bgpdgen.pl -c 5 -n 10.0.0.0/24 -m 26-30
 network 10.0.0.224/28
 network 10.0.0.112/28
 network 10.0.0.0/26
 network 10.0.0.80/28
 network 10.0.0.24/29
Note however Continue reading

6VPE (IPv6 VPN Provider Edge Router)

6VPE is an easy solution to connect IPv6 customers through an existing stable IPv4 MPLS infrastructure. All clients have to do is to connect to a Provider Edge (configured with IPv6 VRFs) using IPv6. I hope this post will provide you with a brief and concise explanation about 6VPE. Let’s start with a short animation […]

Pinging a Firewall – Is It Up Or Down?

Let’s say you’re trying to find a free IP on a network so you can assign one to your PC to do some work. First off, shame on you for not using proper addressing design with an IP address manager software. Second, you might use basic ping tests to properly identify alive hosts vs. dead hosts (free IP addresses). Most do. In fact, you can use nmap to do simple ping sweeps of entire subnets.

Pinging a Firewall – Is It Up Or Down?

Let’s say you’re trying to find a free IP on a network so you can assign one to your PC to do some work. First off, shame on you for not using proper addressing design with an IP address manager software. Second, you might use basic ping tests to properly identify alive hosts vs. dead hosts (free IP addresses). Most do. In fact, you can use nmap to do simple ping sweeps of entire subnets.

Pinging a Firewall – Is It Up Or Down?

Let’s say you’re trying to find a free IP on a network so you can assign one to your PC to do some work. First off, shame on you for not using proper addressing design with an IP address manager software. Second, you might use basic ping tests to properly identify alive hosts vs. dead hosts (free IP addresses). Most do. In fact, you can use nmap to do simple ping sweeps of entire subnets.

Address Learning and the TRILL/FabricPath Control Plane

Do you ever find yourself in a conversation with someone where you attempt to explain a concept in detail and you realize that you don't know that concept at the level of detail that you thought you did? That happened to me recently. I thought I had a better handle on TRILL and FabricPath than I really did. Since I retain things far better when I write them down, I'm going to blog the differences between TRILL and FabricPath when it comes to address learning and what role the control plane plays in building the network topology

CCNA Datacenter

I passed 640-916 - Introducing Cisco Data Center Technologies earlier this week. I was going to publish this post on they day of or after the pass, but unfortunately I was put out of commission by the winter bug that’s going around and did not get to give this post the attention it deserved. The first test in the CCNA Datacenter track, which is 640-911 - Introducing Cisco Data Center Networking, was a pretty straightforward test for someone with my background.

CCNA Datacenter

I passed 640-916 - Introducing Cisco Data Center Technologies earlier this week. I was going to publish this post on they day of or after the pass, but unfortunately I was put out of commission by the winter bug that’s going around and did not get to give this post the attention it deserved. The first test in the CCNA Datacenter track, which is 640-911 - Introducing Cisco Data Center Networking, was a pretty straightforward test for someone with my background.

Multiple Probes In Serverfarm Configuration

Serverfarms allow probes to be associated with them when configured.

Any rserver in the serverfarm configuration will inherit probes from the serverfarm config.

Default probe behaviour is to use OR logic. A single probe failure will cause the rserver to be marked as down.

AND logic for probes can be applied using the fail-on-all command. This means all probes must fail for the serverfarm to be marked as down.


Multicast on TRIO

This post describes how multicast Next-Hop resolution and caching is done on Junos MX routers with Trio based cards. To have more information regarding the multicast replication see my previous post here : Multicast Replication. 1/ Introduction: PIM join...

Multicast on TRIO

This post describes how multicast Next-Hop resolution and caching is done on Junos MX routers with Trio based cards. To have more information regarding the multicast replication see my previous post here : Multicast Replication. 1/ Introduction: PIM join...

Multicast on TRIO

This post describes how multicast Next-Hop resolution and caching is done on Junos MX routers with Trio based cards. To have more information regarding the multicast replication see my previous post here : Multicast Replication. 1/ Introduction: PIM join...
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