How do you know your change won’t cause problems to network? Traditional network engineering relies on robust Change Review processes plus CCIE-level knowledge combined with smart-hands to ensure that. More modern approaches aim to solve this problem with a DevOps mindset that would include multiple layers of testing.
In Networking it’s very expensive to have an environment like production for testing. One possible approach is having some type of a virtual networking lab. We’ve been playing around with an opensource tool called Netsim-tools and below we give an overview of the tool and describe the installation process.
Netsim-tools is bringing IAC to your networking labs. Instead of wasting time creating lab topology in a GUI and configuring boring details, you’ll start with a lab preconfigured according to your specifications. Netsim allows you to:
- Describe high-level lab topology in YAML format without worrying about the specific implementation details
- Use the same lab topology with multiple virtualization providers (Virtualbox, KVM/libvirt, Docker containers)
- Create Vagrant configuration files and Ansible inventory from the lab topology
In a future post, we will create an actual topology, for now, let’s focus on the installation procedure.
- Arista vEOS
- Cisco IOSv
- Cisco CSR 1000v
- Cisco Nexus 9300v
- Cumulus Linux
- Cumulus Linux 5.0 (NVUE)
- Fortinet FortiOS
- FRR 7.5.0
- Generic Linux host
- Juniper vSRX 3.0
- Mikrotik CHR RouterOS
- Nokia SR Linux
- Nokia SR OS
- VyOS
- Dell OS10
Read more about supported devices in:
netsim-tools.readthedocs
Installation
Now, let’s install the Netsim. The install process are automated, you can copy and paste this script on your Ubuntu 20.04, but some requirements are indispensable:
Server requeriments:
• 4 CPUs
• 8 GB MEM
• 64 GB Disk
• Ansible
• Python3 with pip
Please read the comments and adjust to yours needs, but if you have a new server or if you can remove old versions of Python and Ansible, maybe be the better way.
Installation with Ansible:
# you can copy/paste and run all this text.
# you can choose not update your system and Python
# but we recommend to do this to avoid some troubles with Ansible
# can you update your system? uncomment this step
# apt update && apt -y upgrade && apt -y autoremove
# can you update your Python? uncomment these two step under
# apt remove -y python3 ansible ansible-core
# apt install python3-pip
# adjust the step "ADJUSTING TIME TO AVOID ISSUE" to your timezone if the script do not work
# Update your pip and install Ansible to run de playbook
pip install --upgrade pip
pip install ansible ansible-core
# create playbook in netsim-install.pb file
cat > netsim-install.pb << EOF
---
- hosts: localhost
gather_facts: no
tasks:
- name: "[ UPDATING SYSTEM PACKAGES ]"
apt:
update_cache: yes
upgrade: full
autoremove: yes
register: aptout
- name: "[ INSTALLING DEPENDENCIES OF NETLAB ]"
apt:
name: "{{ pkgs }}"
state: present
vars:
pkgs:
- python3-pip
- vagrant-libvirt
- name: "[ UPDATING PIP ]"
shell:
cmd: "pip install --upgrade pip"
- name: "[ INSTALLING NETSIM-TOOL WITH PIP ]"
pip:
name: "netsim-tools"
- name: "[ INSTALLING NETLAB PACKAGES ]"
shell:
cmd: "netlab install -y ubuntu ansible libvirt containerlab"
- name: "[ ADJUSTING TIME TO AVOID ISSUES ]"
shell:
cmd: "timedatectl set-timezone $(cat /etc/timezone) && timedatectl --adjust-system-clock"
- name: "[ TESTING KVM LIBVIRT SUPPORT ]"
shell:
cmd: "kvm-ok"
register: kvmout
ignore_errors: True
- debug:
msg: "{{ kvmout }}"
EOF
# run the PB and run the netlab test if PB pass
ansible-playbook ./netsim-install.pb && netlab test libvirtWe really expect that you reach theses objectives and get something like this:
When Netsim(netlab) script finishs, automatically the lab its detroyed, evidencing that all requirements are done. Well, its that all, good run and enjoy!
fonts:
https://github.com/ipspace/netsim-tools
https://netsim-tools.readthedocs.io