Using a customer nameserver often requires disabling the DHCP based resolv.conf modifications. Here is what I got to work.
Continue readingUsing nmcli to set nameservers
6
Category Archives: Sysadmin
Reading Linux groups via the Rust Foreign Function Interface
The world continues to embraces Rust for its safety properties. While writing utilities in Rust, we are going to have to work with existing code to perform common tasks. I recently needed to list the set of Linux groups registered on a system, and get access to the users assigned to each. Here’s my notes of what I learned.
Continue readingAnsible and FreeIPA Part 2
After some discussion with Bill Nottingham I got a little further along with what it would take to integrate Ansible Tower and FreeIPA. Here are the notes from that talk.
Continue readingAnsible and FreeIPA Part-1
Ansible is a workflow engine. I use it to do work on my behalf.
FreeIPA is an identity management system. It allows me to manage the identities of users in my organization
How do I get the two things to work together? The short answer is that it is trivial to do using Ansible Engine. It is harder to do using Ansible tower.
Edit: Second part is here. Third part is coming.
Continue readingYour Own, Personal, Ansible
Me. Us. Them.
The story I tell when I explain the various offereings that Red Hat has based on Ansible follow is based on the progression of Me. Us. Them.
Me: Get my playbook working for me on my workstation. For this, I use Ansible Engine.
Us: Share my playbook with my larger team. For this, I use Ansible Tower.
Them: Make a Self service catalog for the larger organization to consume. This is where Ansible integration into other products comes in to play. I typically talk about CloudForms integration here, but Satellite and OpenShift are also capable of making use of Ansible here.
Here is how I have my local setup for doing Ansible based development. This is organized roughly around how Tower will later consume the roles and playbooks I design here.
Continue readingTripleO Networks from Simplest to Not-So-Simple
If you read the TripleO setup for network isolation, it lists eight distinct networks. Why does TripleO need so many networks? Lets take it from the ground up.
Continue reading
Remotely Provisioning a Virtual Machine using Ansible and Libvirt
Ansible exists to help automate the time consuming repeated tasks that technologist depend upon. One very common jobs is to create and tear down a virtual machine. While cloud technologies have made this possible to perform remotely, there are many times when I’ve needed to setup and tear down virtual machines on systems that were stand alone Linux servers. In this case, the main interfaces to the machine are ssh and libvirt. I recently worked through an Ansible role to setup and tear down an virtual machine via libvirt, and I’d like to walk through it, and record my reasons for some of the decisions I made.
Continue reading
Mapping Network Ports from Physical to Logical
The Workstation on top of my server rack has 3 Ethernet ports. One is built in to the mother board, and and two are on a card. I want to use these three ports for different purposes. How can I tell which is which internally? The answer lies in /sys/bus/pci/devices/.
Launching a VM From the virt-install command line interface
I do this infrequently enough that I want to record a reminder how I do it:
sudo cp ~/Downloads/rhel-server-7.6-x86_64-kvm.qcow2 /var/lib/libvirt/images/tower.qcow2 sudo virt-install --vcpus=2 --name tower --ram 4096 --import --disk /var/lib/libvirt/images/tower.qcow2 |
Manually Adding SSH Keys to a Cloud Image
Not all of my virtual machines run on OpenStack; I have to run a fair number of virtual machines on my personal workstation via libvirt. However, I like using the cloud versions of RHEL, as they most closely match what I do run in OpenStack. The disconnect is that the Cloud images are designed to accept cloud-init, which pulls the ssh public keys from a metadata web server. Without that, there are no public keys added to the cloud-user account, and the VM is unaccessable. Here is how I add the ssh keys manually.
Continue reading