6.1 Explain how automation impacts network management

Eventually, the first five chapters of this book will become obsolete and all networks will be automated.

Automation allows us to configure a network without thinking about the granular management of each physical device.  Instead of configuring VLANs, duplex, speed, PoE, etc on each switch port, we create policies that tell us how the network will function.  A controller interprets those policies and automatically configures the devices.

Network Management also allows us to automatically gather data from multiple devices and verify that they are functional.  We can be alerted in the event of an issue.

I mentioned the “show” command many times in this book.  Think about the output of the show ip interface brief command.

It tells us the status of each router interface, including its IP address and whether it is up or down.

Now think about how we could obtain this information from each router automatically

• We would need a list of router IP addresses
• We would create a script that automatically logged in to each router
• The script would enter the enable mode and enter the enable password
• It would write the show ip interface brief command and record the output
• We would create another script and use it to process the results from the output, including the types of interfaces available and their status.  It would have to understand the columns from each output.
• If we had different models of routers that required different commands, the script would need to figure out which command to enter for each router.
  
  If each model of router provided the output in a different format, our script would need to interpret the different formats.

We can use this data to create a graphical user interface or store it in a database.  With a script, we don’t have to manually log in to each router and check its status.  We can look at a dashboard and automatically see the status of dozens or hundreds of router interfaces at the same time.

It is much easier to automate a network when devices allow us to automatically collect data.  That requires some effort on the part of the manufacturer. 

Some of the benefits of automatic device configuration

• We can configure each device from a template, instead of manually.  This reduces the risk of error. 
• We can change device configuration based on the time of day or day of the week, which would not be possible if we had to do so manually. 
• We can change device configuration based on user demand. 
• We are better able to analyse data.

An example of an automation tool is the Cisco Meraki dashboard