From 8fe50bea77a10267be61388c90357c126e54a3d7 Mon Sep 17 00:00:00 2001 From: "Joshua M. Boniface" Date: Sat, 11 Apr 2020 01:22:07 -0400 Subject: [PATCH] Add FAQ to documentation --- docs/faq.md | 49 +++++++++++++++++++++++++++++++++++++++++++++++++ docs/index.md | 2 +- 2 files changed, 50 insertions(+), 1 deletion(-) create mode 100644 docs/faq.md diff --git a/docs/faq.md b/docs/faq.md new file mode 100644 index 00000000..06469a82 --- /dev/null +++ b/docs/faq.md @@ -0,0 +1,49 @@ +# Frequently Asked Questions about Parallel Virtual Cluster + +## General Questions + +### What is it? + +PVC is a virtual machine management suite designed around high-availability. It can be considered an alternative to ProxMox, VMWare, Nutanix, and other similar solutions that manage not just the VMs, but the surrounding infrastructure as well. + +### Why would you make this? + +The full story can be found in the [about page](https://parallelvirtualcluster.readthedocs.io/en/latest/about), but after becoming frustrated by numerous other management tools, I discovered that what I wanted didn't exist as FLOSS software, so I built it myself. + +### Is PVC right for me? + +PVC might be right for you if your requirements are: + +1. You need KVM-based VMs. +2. You want management of storage and networking (a.k.a. "batteries-included") in the same tool. +3. You want hypervisor-level redundancy, able to tolerate hypervisor downtime seamlessly, for all elements of the stack. + +I built PVC for my homelab first, found a perfect usecase with my employer, and think it might be useful to you too. + +### Is 3 hypervisor really the minimum? + +For a redundant cluster, yes. PVC requires a majority quorum for several subsystems, and the smallest possible majority quorum is 2/3. That said, you can run PVC on a single node for testing/lab purposes without host-level reundancy. + +## Feature Questions + +### Does PVC support Docker/Kubernetes/LXC/etc. + +No. PVC supports only KVM VMs. To run Docker containers, etc., you would need to run a VM which then runs your containers. + +### Does PVC have a WebUI? + +Not yet. Right now, PVC management is done almost exclusively with an API and the included CLI interface to that API. A WebUI could and likely will be built in the future, but I'm not a frontend developer. + +## Storage Questions + +### Can I use RAID-5 with PVC? + +The short answer is no. The long answer is: Ceph, the storage backend used by PVC, does support "erasure coded" pools which implement a RAID-5-like functionality. PVC does not support this for several reasons. If you use PVC, you must accept at the very least a 2x storage penalty, and for true safety and resiliency a 3x storage penalty, for VM storage. This is a trade-off of the architecture. + +### Can I use spinning HDDs with PVC? + +You can, but you won't like the results. SSDs are effectively required to obtain any sort of reasonable performance when running multiple VMs. Ideally, datacentre-grade SSDs as well, due to their significantly increased write endurance. + +### What Ceph version does PVC use? + +PVC requires Ceph 14.x (Nautilus). The official PVC repository includes Ceph 14.2.8. Debian Buster by default includes only 12.x (Luminous). diff --git a/docs/index.md b/docs/index.md index 8bc3feb5..131e82d1 100644 --- a/docs/index.md +++ b/docs/index.md @@ -15,7 +15,7 @@ The major goal of PVC is to be administrator friendly, providing the power of En ## Getting Started -To get started with PVC, read the [Cluster Architecture document](https://parallelvirtualcluster.readthedocs.io/en/latest/architecture/cluster/), then see [Installing](https://parallelvirtualcluster.readthedocs.io/en/latest/installing) for details on setting up a set of PVC nodes, using the [PVC Ansible](https://parallelvirtualcluster.readthedocs.io/en/latest/manuals/ansible) framework to configure and bootstrap a cluster, and managing it with the [`pvc` CLI tool](https://parallelvirtualcluster.readthedocs.io/en/latest/manuals/cli) or [RESTful HTTP API](https://parallelvirtualcluster.readthedocs.io/en/latest/manuals/api). For details on the project, its motivation, and architectural details, see [the About page](https://parallelvirtualcluster.readthedocs.io/en/latest/about). +To get started with PVC, read the [Cluster Architecture document](https://parallelvirtualcluster.readthedocs.io/en/latest/architecture/cluster/) and [Frequently Asked Questions](https://parallelvirtualcluster.readthedocs.io/en/latest/architecture/faq/), then see [Installing](https://parallelvirtualcluster.readthedocs.io/en/latest/installing) for details on setting up a set of PVC nodes, using the [PVC Ansible](https://parallelvirtualcluster.readthedocs.io/en/latest/manuals/ansible) framework to configure and bootstrap a cluster, and managing it with the [`pvc` CLI tool](https://parallelvirtualcluster.readthedocs.io/en/latest/manuals/cli) or [RESTful HTTP API](https://parallelvirtualcluster.readthedocs.io/en/latest/manuals/api). For details on the project, its motivation, and architectural details, see [the About page](https://parallelvirtualcluster.readthedocs.io/en/latest/about). ## Changelog