This demo demonstrates how to configure an out of band management network to automatically install and configure Cumulus Linux using Zero Touch Provisioning, and validate the cabling of the switches using Prescriptive Topology Manager.
This demo is written for the cldemo-vagrant reference topology.
Before running this demo, install VirtualBox and Vagrant. The currently supported versions of VirtualBox and Vagrant can be found on the cldemo-vagrant.
git clone https://github.com/cumulusnetworks/cldemo-vagrant
cd cldemo-vagrant
vagrant up oob-mgmt-server oob-mgmt-switch leaf01 leaf02 spine01 spine02 server01 server02
vagrant ssh oob-mgmt-server
sudo su - cumulus
git clone https://github.com/cumulusnetworks/cldemo-onie-ztp-ptm
cd cldemo-onie-ztp-ptm
sudo apt-get update
sudo apt-get install -qy apache2 isc-dhcp-server bind9
sudo cp ./etc/network/interfaces /etc/network
sudo cp ./etc/dhcp/* /etc/dhcp
sudo cp ./etc/bind/zones/* /etc/bind/zones
sudo cp ./etc/bind/named.conf.options /etc/bind
sudo cp ./var/www/* /var/www
cp example_private_key ~/.ssh/id_rsa
cp example_public_key ~/.ssh/id_rsa.pub
chmod 0700 -R ~/.ssh/
sudo cp example_public_key /var/www/id_rsa.pub
sudo ifdown eth1
sudo ifup eth1
sudo service isc-dhcp-server restart
sudo service bind9 restart
ssh leaf01
sudo su
ifdown eth0; ifup eth0
exit
ptmctl
This demo runs on a spine-leaf topology with two single-attached hosts. Each device's management interface is connected to an out-of-band management switch and bridged with the out-of-band management server that runs our webserver, DHCP server, and DNS server.
+------------+ +------------+
| spine01 | | spine02 |
| | | |
+------------+ +------------+
swp1 | swp2 \ / swp1 | swp2
| X |
swp51 | swp52 / \ swp51 | swp52
+------------+ +------------+
| leaf01 | | leaf02 |
| | | |
+------------+ +------------+
swp1 | | swp2
| |
eth1 | | eth2
+------------+ +------------+
| server01 | | server02 |
| | | |
+------------+ +------------+
During the quick start, we install and configure three major services on the out of band management server.
- Apache Webserver: allows the management server to deliver ONIE install images and ZTP scripts to the nodes.
- ISC DHCP Server: sends IP addresses, hostnames, and the ONIE/ZTP DHCP options to the nodes.
- Bind9 Nameserver: provides DNS to the nodes (not strictly necessary, but very convenient)
If you are using the cldemo-vagrant topology, you will find that many of these services are already installed and running, so these steps exist to show you how to set things up if you were provisioning on hardware.
When a node running Cumulus Linux comes online and performs DHCPDISCOVER, it will download and run the zero touch provisioning script specified in /etc/dhcp/dhcpd.pools. This script performs four common functions:
- Enables passwordless sudo, which makes driving the switch much easier.
- Adds a public key to the cumulus user, enabling passwordless SSH as well.
- Licenses the switch (only needed on physical hardware)
- Restarts switchd (for licensing to take effect)
- Sets all ports to ADMIN_UP (for PTM)
- Downloads the topology.dot file from the oob-mgmt-server
- Restarts PTM (to read the topology file)