Explaining Network Automation and SDN
What is it -> It is the Cure to repetition.
| W | I | D | G | E | T |
| Wonder “Question the norm” | Invention People that want to create smth. | Discernment The intuitive knack for evaluating ideas | Galvanizing The talent for inspiring | Enablement The supportive drive to offer assistance | Tenacity The determination to push tasks through |
| Innovation | Activation | Doing-Phase | |||
All cisco devices can be broken up in to three pieces:
| Management |
| Control Plane |
| Data Plane |
SDN -> Software defined networking is just something that controls the control plane. It is going beyond the management plane and centralize and automate it.
An example of SDN is a WLC connected to his light weight access points (LWAP). The access points have no brain at all they just get data and move it to the switch network if you want to say so. The WLC is all the intelligence of the LWAP. The only thing that stays on the device is the data plane. So the process of forwarding packets is the data plane.
For example OSPF works at the control plane, and that’s a thinking process and that is consuming time.
OPENVIEW, NETCONF, OPFLEX, SSH and SNMP these protocols are designed to try and automate the management and the control plane part of the device.
Exploring Cisco SDN Models and Platforms
SDN is all powered by API’s.
Cisco SD-Access
Used for LAN / Campus models, uses VxLAN.
Cisco SD-WAN
Software defined WAN, it makes the WAN much more seamless, blends it all together and for the end user it seems it is all connected.
Cisco ACI (Data center)
Cisco application centric infrastructure is the model for managing data centers. Uses as well VxLAN.
VxLAN is just like a VPN but not on the internet, though in your own network. Applications can create virtual LAN’s on the fly and talk to the controller or to talk to each other.
Cisco DNAC (now Catalyst center) is the platform to manage Cisco SD-Access and Cisco SD-WAN.
Ciscp APIC is the same thing, but the platform which is being used to manage data centers.
Working with RESTful APIs
What is a “RESTFUL API”
In HTTP there is a language of communication, that is called a restful interface.
Aaah.. C.R.U.D.
Language of restful APIs:
- CREATE
- READ
- UPDATE
- DELETE
Responses
- 1xx Informational
- 2xx Success
- 3xx Redirect
- 4xx Client error
- 5xx Server error
Anything that adopts that framework is known as a restful interface.
Postman
Use this to manually interact with APIs.
Token
When you use Postman for example and authenticate with username and password, the API gives you back a token. A token is a looooooong set of numbers and letters which you include if you ever do such a C.R.U.D request, so the API knows you are authenticated. But a token can be dangerous, because with that token you could theoretically access without username and password the API.
Glancing at Ansible, Puppet, Chef and Markup Languages
Technical dead
The situation “aah we did that 5 years ago noone knows why.”
Ansible, Puppet and Chef
These are all network automation tools and are all based on linux.
Ansible is mostly used for network devices and Puppet and Chef are mostly used for servers. The require an agent installed on the device.
Ansible is agent less, meaining it can mange devices directly using protocols like SSH.
- The simplest walk through to set up ansible
Ansible goes out to the devices and run its playbooks, so all the configurations are consistent.
YAML, XML and JSON
XML -> extensible markup language
Miniature database that ansible can call on, and in the playbook we say something like for the IP-Address we set the IP to <xy>
JSON -> another type of markup language
YAML -> yet another markup language
Super simple, like title column, publisher column etc.