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What Certifications Are Not

What Certifications Are Not

My colleague and I had a discussion about the role certifications play in one’s career. Our opinions on the topic were almost aligned. The discussion took an interesting turn when it shifted towards how certifications should not be applied in the workplace.

The topic of certifications can become a heated one and if you’d like to provide constructive input, I’d like you to engage below in the comments.

I believe there is value to having certifications but only when used in conjunction with experience and mindset.

There are people who, in my opinion, take the wrong approach to certifications. I see it mostly with those entering the industry or those trying to advance themselves.

Not a guaranteed way to get a jobContinue Reading…

How To Configure Cisco NetFlow

Cisco NetFlowNetFlow is used to collect data flows from interfaces. The information can be stored on the switch but more commonly sent to a server which collects the NetFlow data and spits it out into something shiny. Okay, not shiny but data more easily digestible.

Each packet is looked at for a set of IP packet attributes which are called key fields. The key fields help determine if the information within a packet is unique or similar to the other packets. If there are new values in the key fields then a new flow is created.

With that data you can create trend reports or gather protocol and interface statistics. In near real time you can find out who your top talkers are and what your most widely used protocols are traversing your network. It can even act as a security tool in finding network anomalies.

Netflow has 4 components:

  • Records
  • Exporter
  • Monitor
  • Sampler

The following NetFlow configuration was tested on a Cisco Catalyst 3850 running IOS version 15. On the Catalyst 3850, the exact version used is Flexible NetFlow (FNF). You will need at least IP Base licensing to use NetFlow. In short, Flexible NetFlow is Cisco’s migration from the traditional NetFlow. Aw how cute, it’s growing up.

Here is the full configuration I ended up with. After the configuration I go into more detail.

flow record AUNTFLOW
 match ipv4 destination address
 match ipv4 source address
 match ipv4 protocol
 match interface input
 match transport destination-port
 match transport source-port
 collect counter bytes long
 collect counter packets long
 collect interface input
 collect transport tcp flags
 collect timestamp absolute first
 collect timestamp absolute last
 !
 !
 flow exporter AUNTFLOWEXPORT
 description Export to netflow system
 destination 192.168.1.10
 source vlan 10
 transport udp 4739
 ttl 60
 !
 !
 flow monitor AUNTFLOWMON
 description Netflow monitor
 exporter AUNTFLOWEXPORT
 record AUNTFLOW
 cache timeout active 30
 !
 !
 sampler AUNTFLOWSAMPLER
 description AUNTFLOW
 mode random 1 out-of 32
 !
 !
 interface range g1/0/1 - 48
 ip flow monitor AUNTFLOWMON sampler AUNTFLOWSAMPLER input

Step 1: Configure the Records

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Cisco Live 2015 – John Chambers Tribute Video

I wasn’t able to make it to Cisco Live 2015 in San Diego but I was kind of there.. in video! As part of John Chambers’ farewell I took part in saying some kind words.

Take a look at the video and you will see me, Rowell Dionicio.