Getting started with Jenkins for Network Automation

As I have mentioned my previous post about Getting started with Gitlab-CI for Network Automation, Jenkins is another continuous integration pipelining tool you can use for network automation. Have a look about how to install Jenkins: https://wiki.jenkins.io/display/JENKINS/Installing+Jenkins+on+Ubuntu

To use the Jenkins with Vagrant and KVM (libvirt) there are a few changes needed on the linux server similar with the Gitlab-Runner. The Jenkins user account needs to be able to control KVM and you need to install the vagrant-libvirt plugin:

usermod -aG libvirtd jenkins
sudo su jenkins
vagrant plugin install vagrant-libvirt

Optional: you may need to copy custom Vagrant boxes into the users vagrant folder ‘/var/lib/jenkins/.vagrant.d/boxes/*’. Note that the Jenkins home directory is not located under /home.

Now lets start configuring a Jenkins CI-pipeline, click on ‘New item’:

This creates an empty pipeline where you need to add the different stages  of what needs to be executed:

Below is an example Jenkins pipeline script which is very similar to the Gitlab-CI pipeline I have used with my Cumulus Linux Lab in the past.

pipeline {
    agent any
    stages {
        stage('Clean and prep workspace') {
            steps {
                sh 'rm -r *'
                git 'https://github.com/berndonline/cumulus-lab-provision'
                sh 'git clone --origin master https://github.com/berndonline/cumulus-lab-vagrant'
            }
        }
        stage('Validate Ansible') {
            steps {
                sh 'bash ./linter.sh'
            }
        }
        stage('Staging') {
            steps {
                sh 'cd ./cumulus-lab-vagrant/ && ./vagrant_create.sh'
                sh 'cd ./cumulus-lab-vagrant/ && bash ../staging.sh'
            }
        }
        stage('Deploy production approval') {
            steps {
                input 'Deploy to prod?'
            }
        }
        stage('Production') {
            steps {
                sh 'cd ./cumulus-lab-vagrant/ && ./vagrant_create.sh'
                sh 'cd ./cumulus-lab-vagrant/ && bash ../production.sh'
            }
        }
    }
}

Let’s run the build pipeline:

The stages get executed one by one and, as you can see below, the production stage has an manual approval build-in that nothing gets deployed to production without someone to approve before, for a controlled production deployment:

Finished pipeline:

This is just a simple example of a network automation pipeline, this can of course be more complex if needed. It should just help you a bit on how to start using Jenkins for network automation.

Please share your feedback and leave a comment.

Getting started with Gitlab-CI for Network Automation

Ken Murphy from networkautomationblog.com asked me to do a more detailed post about how to setup Gitlab-Runner on your local server to use with Gitlab-CI. I will not get into too much detail about the installation because Gitlab has a very detailed information about it which you can find here: https://docs.gitlab.com/runner/install/linux-repository.html

Once the Gitlab Runner is installed on your server you need to configure and register the runner with your Gitlab repo. If you are interested in information about this, you can find the documentation here: https://docs.gitlab.com/runner/register/ but lets continue with how to register the runner.

In your project go to ‘Settings -> CI / CD’ to find the registration token:

It is important to disable the shared runners:

Now let’s register the gitlab runner:

[email protected] ~ # sudo gitlab-runner register
Running in system-mode.

Please enter the gitlab-ci coordinator URL (e.g. https://gitlab.com/):
https://gitlab.com
Please enter the gitlab-ci token for this runner:
xxxxxxxxx
Please enter the gitlab-ci description for this runner:
[lab]:
Please enter the gitlab-ci tags for this runner (comma separated):
lab
Whether to run untagged builds [true/false]:
[false]: true
Whether to lock the Runner to current project [true/false]:
[true]: false
Registering runner... succeeded                     runner=xxxxx
Please enter the executor: docker-ssh, parallels, ssh, virtualbox, kubernetes, docker, shell, docker+machine, docker-ssh+machine:
shell
Runner registered successfully. Feel free to start it, but if it's running already the config should be automatically reloaded!
[email protected] ~ #

You will find the main configuration file under /etc/gitlab-runner/config.toml.

When everything goes well the runner is registered and active, and ready to apply the CI pipeline what is defined in the .gitlab-ci.yml.

To use the runner with Vagrant and KVM (libvirt) there are a few changes needed on the linux server itself, first the gitlab-runner user account needs to be able to control KVM, second the vagrant-libvirt plugin needs to be installed:

usermod -aG libvirtd gitlab-runner
sudo su gitlab-runner
vagrant plugin install vagrant-libvirt

Optional: you may need to copy custom Vagrant boxes into the users vagrant folder ‘/home/gitlab-runner/.vagrant.d/boxes/*’.

Here the example from my Cumulus CI-pipeline .gitlab-ci.yml that I have already shared in my other blog post about Continuous Integration and Delivery for Networking with Cumulus Linux:

---
stages:
    - validate ansible
    - staging
    - production
validate:
    stage: validate ansible
    script:
        - bash ./linter.sh
staging:
    before_script:
        - git clone https://github.com/berndonline/cumulus-lab-vagrant.git
        - cd cumulus-lab-vagrant/
        - python ./topology_converter.py ./topology-production.dot
          -p libvirt --ansible-hostfile
    stage: staging
    script:
        - bash ../staging.sh
production:
    before_script:
        - git clone https://github.com/berndonline/cumulus-lab-vagrant.git
        - cd cumulus-lab-vagrant/
        - python ./topology_converter.py ./topology-production.dot
          -p libvirt --ansible-hostfile
    stage: production
    when: manual
    script:
        - bash ../production.sh
    only:
        - master

The next step is the staging.sh shell script which boots up the vagrant instances and executes the Ansible playbooks. It is better to use a script and report the exit state so that if something goes wrong the Vagrant instances are correctly destroyed.

#!/bin/bash

EXIT=0
vagrant up mgmt-1 --color <<< 'mgmt-1 boot' || EXIT=$?
vagrant up netq-1 --color <<< 'netq-1 boot' || EXIT=$?
sleep 300
vagrant up spine-1 --color <<< 'spine-1 boot' || EXIT=$?
vagrant up spine-2 --color <<< 'spine-2 boot' || EXIT=$?
sleep 60
vagrant up edge-1 --color <<< 'edge-1 boot' || EXIT=$?
vagrant up edge-2 --color <<< 'edge-2 boot' || EXIT=$?
sleep 60
vagrant up leaf-1 --color <<< 'leaf-1 boot' || EXIT=$?
vagrant up leaf-2 --color <<< 'leaf-2 boot' || EXIT=$?
vagrant up leaf-3 --color <<< 'leaf-3 boot' || EXIT=$?
vagrant up leaf-4 --color <<< 'leaf-4 boot' || EXIT=$?
vagrant up leaf-5 --color <<< 'leaf-5 boot' || EXIT=$?
vagrant up leaf-6 --color <<< 'leaf-6 boot' || EXIT=$?
sleep 60
vagrant up server-1 --color <<< 'server-1 boot' || EXIT=$?
vagrant up server-2 --color <<< 'server-2 boot' || EXIT=$?
vagrant up server-3 --color <<< 'server-3 boot' || EXIT=$?
vagrant up server-4 --color <<< 'server-4 boot' || EXIT=$?
vagrant up server-5 --color <<< 'server-5 boot' || EXIT=$?
vagrant up server-6 --color <<< 'server-6 boot' || EXIT=$?
sleep 60
export ANSIBLE_FORCE_COLOR=true
ansible-playbook ./helper_scripts/configure_servers.yml <<< 'ansible playbook' || EXIT=$?
ansible-playbook ../site.yml <<< 'ansible playbook' || EXIT=$?
sleep 60
ansible-playbook ../icmp_check.yml <<< 'icmp check' || EXIT=$?
vagrant destroy -f
echo $EXIT
exit $EXIT

Basically any change in the repository triggers the .gitlab-ci.yml and executes the pipeline; starting with the stage validating the Ansible syntax:

Continue with staging the configuration and deploying to production. The production stage is a manual trigger to have a controlled deployment:

In one of my next posts I will explain how to use Jenkins instead of Gitlab-CI for Network Automation. Jenkins is very similar to the runner but more flexible with what you can do with it.

Leave a comment

Ansible Playbook for Cisco ASAv Firewall Topology

More about Ansible network automation with Cisco ASAv and continuous integration testing like in my previous posts using Vagrant and Gitlab-CI.

Network overview:

Here’s my Github repository where you can find the complete Ansible Playbook: https://github.com/berndonline/asa-lab-provision

Automating firewall configuration is not that easy and can get very complicated because you have different objects, access-lists and service policies to configure which all together makes the playbook complex rather than simple.

What you won’t find in my playbook is how to automate the cluster deployment because this wasn’t possible in my scenario using ASAv and Vagrant. I didn’t have physical Cisco ASA firewall on hand to do this but I might add this later in the coming months.

Let’s look at the different variable files I created; first the host_vars for asa-1.yml which is very similar to a Cisco router:

---

hostname: asa-1
domain_name: lab.local

interfaces:
  0/0:
    alias: connection rtr-1 inside
    nameif: inside
    security_level: 100
    address: 10.0.255.1
    mask: 255.255.255.0

  0/1:
    alias: connection rtr-2 outside
    nameif: outside
    security_level: 0
    address: 217.100.100.1
    mask: 255.255.255.0

routes:
  - route outside 0.0.0.0 0.0.0.0 217.100.100.254 1

I then use multiple files in group_vars for objects.ymlobject-groups.ymlaccess-lists.yml and nat.yml to configure specific firewall settings.

Roles:

  • Hostname: The task in main.yml uses the Ansible module asa_config and configures hostname and domain name.
  • Interfaces:  This role uses the Ansible module asa_config to deploy the template interfaces.j2 to configure the interfaces. In the main.yml is a second task to enable the interfaces when the previous template applied the configuration.
  • Routing: Similar to the interfaces role and uses also the asa_config module to deploy the template routing.j2 for the static routes
  • Objects: The first task in main.yml loads the objects.yml from group_vars, the second task deploys the template objects.j2.
  • Object-Groups: Uses same tasks in main.yml and template object-groups.j2 like the objects role but the commands are slightly different.
  • Access-Lists: One of the more complicated roles I needed to work on, in the main.yml are multiple tasks to load variables like in the previous roles, then runs a task to clear access-lists if the variable “override_acl” from access-lists.yml group_vars is set to “true” otherwise it skips the next tasks. When the variable are set to true and the access-lists are cleared it then writes new access-lists using the Ansible module asa_acl and finishes with a task to assigning the newly created access-lists to the interfaces.
  • NAT: This role is again similar to the objects role using a task main.yml to load variable file and deploys the template nat.j2. The NAT role uses object nat and only works if you created the object before in the objects group_vars.
  • Policy-Framework: Multiple tasks in main.yml first clears global policy and policy maps and afterwards recreates them. Similar approach like the access lists to keep it consistent.

Main Ansible Playbook site.yml

---

- hosts: asa-1

  connection: local
  user: vagrant
  gather_facts: 'no'

  roles:
    - hostname
    - interfaces
    - routing
    - objects
    - object-groups
    - access-lists
    - nat
    - policy-framework

When a change triggers the gitlab-ci pipeline it spins up the Vagrant instances and executes the main Ansible Playbook. After the Vagrant instances are booted, first the two router rtr-1 and rtr-2 need to be configured with cisco_router_config.yml, then afterwards the main site.yml will be run.

Once the main playbook finishes for the Cisco ASA a last connectivity check will be execute using the playbook asa_check_icmp.yml. Just a simple ping to see if the base configuration is applied correctly.

If everything goes well, like in this example, the job is successful:

I will continue to improve the Playbook and the CICD pipeline so come back later to check it out.

Leave a comment

Ansible Playbook for Cisco BGP Routing Topology

This is my Ansible Playbook for a simple Cisco BGP routing topology and using a CICD pipeline for integration testing. The virtual network environment is created on-demand by using Vagrant, see my post about Cisco IOSv and XE network simulation using Vagrant.

Network overview:

Here’s my Github repository where you can find the complete Ansible Playbook: https://github.com/berndonline/cisco-lab-provision

You can find all the variables for the interface and routing configuration under host_vars. Below is an example for router rtr-1:

---

hostname: rtr-1
domain_name: lab.local

loopback:
  address: 10.255.0.1
  mask: 255.255.255.255

interfaces:
  0/1:
    alias: connection rtr-2
    address: 10.0.255.1
    mask: 255.255.255.252

  0/2:
    alias: connection rtr-3
    address: 10.0.255.5
    mask: 255.255.255.252

bgp:
  asn: 65001
  neighbor:
    - {address: 10.0.255.2, remote_as: 65000}
    - {address: 10.0.255.6, remote_as: 65000}
  networks:
    - {network: 10.0.255.0, mask: 255.255.255.252}
    - {network: 10.0.255.4, mask: 255.255.255.252}
    - {network: 10.255.0.1, mask: 255.255.255.255}
  maxpath: 2

Roles:

  • Hostname: The task in main.yml uses the Ansible module ios_system and configures hostname, domain name and disables dns lookups.
  • Interfaces: This role uses the Ansible module ios_config to deploy the template interfaces.j2 to configure the interfaces. In the main.yml is a second task to enable the interfaces when the previous template applied the configuration.
  • Routing: Very similar to the interfaces role and uses also the ios_config module to deploy the template routing.j2 for the BGP routing configuration.

Main Ansible Playbook site.yml:

---

- hosts: all

  connection: local
  user: vagrant
  gather_facts: 'no'

  roles:
    - hostname
    - interfaces
    - routing

When a change triggers the gitlab-ci pipeline it spins up the Vagrant instances and executes the main Ansible Playbook:

After the main site.yml ran, a second Playbook is executed for basic connectivity testing cisco_check_icmp.yml. This uses the Ansible module ios_ping and can be useful in my case to validate if the configuration was correctly applied:

If everything goes well, like in this example, the job is successful:

I will continue to improve the Playbook and the CICD pipeline so come back later to check it out.

Leave a comment

Ansible Playbook for Cumulus Linux BGP IP-Fabric and Cumulus NetQ Validation

This is my Ansible Playbook for a Cumulus Linux BGP IP-Fabric using BGP unnumbered and Cumulus NetQ to validate the configuration in a CICD pipeline. I use the same CICD pipeline from my previous post about Continuous Integration and Delivery for Networking with Cumulus Linux but added the Cumulus NetQ validation in the production stage to check BGP and CLAG configuration.

Network overview:

Here’s my Github repository where you find the complete Ansible Playbook: https://github.com/berndonline/cumulus-lab-provision

The variables are split between group_vars and host_vars. Still need to see if I can find a better way for the variables because interface settings for spine and edge switches are in group_vars, and for leaf switches the interface configuration is per host in host_vars. Not ideal at the moment, it should be the same for all devices.

Roles:

  • Hostname: This task changes the hostname
  • Interfaces: This creates the interfaces and bridge (only leafs and edges) configuration. The task uses templates interfaces.j2 and interfaces_config.j2 to create the configuration files under /etc/network/…
  • Routing: The template frr.j2 creates the FRR (Free Range Routing) configuration file. FRR replaces Quagga since Cumulus Linux version 3.4.x
  • PTM: Uses as well an template topology.j2 to generate the topology file for the Prescriptive Topology Manager (PTM)
  • NTP: Ntp and timezone settings

In most of the cases I use Jinja2 templates to generate configuration files. The site.yml is otherwise very simple. It executes the different roles, and triggers the handlers if a change is made by a role.

---

- hosts: network
  strategy: free

  user: cumulus
  become: 'True'
  gather_facts: 'False'

  handlers:
    - name: reload networking
      command: "{{item}}"
      with_items:
        - ifreload -a
        - sleep 10

    - name: reload frr
      service: name=frr state=reloaded

    - name: apply hostname
      command: hostname -F /etc/hostname

    - name: restart netq agent
      command: netq config agent restart

    - name: reload ptmd
      service: name=ptmd state=reloaded

    - name: apply timezone
      command: /usr/sbin/dpkg-reconfigure --frontend noninteractive tzdata

    - name: restart ntp
      service: name=ntp state=restarted

  roles:
    - hostname
    - interfaces
    - routing
    - ptm
    - ntp

Like mentioned in previous posts, I use Gitlab-CI for my Continuous Integration / Continuous Delivery (CICD) pipeline to simulate changes against a virtual Cumulus Linux network using Vagrant. You can find more information about the pipeline configuration in the .gitlab-ci.yml.

Changes in the staging branch will spin-up the Vagrant environment but only executes the the Ansible Playbook:

Cumulus NetQ configuration validation in production:

The production stage in the pipeline spins-up the Vagrant environment and executes the Ansible Playbook, then continues executing the two NetQ checks netq_check_bgp.yml and netq_check_clag.yml to validate the BGP and CLAG configuration:

The result will look like this when all stages finish successfully:

I will continue to improve the Playbook and the CICD pipeline so come back later to check it out.

In my repository I have some other useful Playbooks for config backup and restore but also to collect and remove cl-support.

config_backup.yml

config_restore.yml

cl-support_get.yml

cl-support_remove.yml

Please tell me if you like it and share your feedback.

See my new post about BGP EVPN and VXLAN with Cumulus Linux

Leave a comment