Talk:Xen Project Beginners Guide

Is the Guide Ready?

--Lars.kurth 15:44, 6 December 2011 (UTC) Hey Joseph, thanks for doing all this work. Let me know when you feel comfortable enough to publish the page on Category:Beginners. I was thinking of creating a new trailbox or including it into one of the existing ones at the top of the category.

--JosephGlanville Hi Lars, thanks for the props and apologies it has taken me so long to get back to this. Very busy at this stage in time. I will polish the guide off over the Christmas break and we can push it through then. :)

HELP

Hi Guys, I am trying to follow the guide for a test installation but unfortunately the link provided to Debian OS is non functional. Im not so sure if i can download a random OS, so can you please double check or confirm if any version would suffice, thank you.

--JosephGlanville Hi, this has been fixed. Sorry for the confusion.

• --Lars.kurth 13:15, 8 June 2012 (UTC) Joseph, can you check out Xen_Overview for the missing bits as well as Category:Debian for links to Debian?

Xen Project Document Day is This Wednesday, July 30: Beginner's Guide needs [updating](Russ Pavlicek)

This is a reminder that next Wednesday, July 30, is Xen Project Document Day.

Xen Project Document Day is a day to help improve overall Xen Project documentation, particularly that of the Wiki.

This month, it would be great if we could include the incomplete bits needed for the Beginner's Guide, including at least one decent diagram and some of the missing information called out in the Architecture section:

http://wiki.xenproject.org/wiki/Xen_Project_Beginners_Guide

All the information you need to participate in Document Day is here:

http://wiki.xenproject.org/wiki/Xen_Document_Days

If you get a few moments in the next week, please take a look at the current TODO list to see other items which need attention:

http://wiki.xenproject.org/wiki/Xen_Document_Days/TODO

So please think about how you can help out. If you haven't requested to be made a Wiki editor, save time and do it now so you are ready to go on Document Day. Just fill out the form below:

http://xenproject.org/component/content/article/100-misc/145-request-to-be-made-a-wiki-editor.html

We hope to see you Wednesday in #xendocs!

--Rich.T. If somebody here can provide a pencil sketch of:

A brief look at Xen Project architecture

To understand how storage, networking and other resources are delivered to guest systems we need to quickly delve into how the different bits of the software interact.

<todo diagram>

... and link to it here; I will try to put together a professional-looking diagram using https://www.lucidchart.com/

Example: https://drive.google.com/file/d/0B_kSZeNQ1ivtV3phSVY5MHFqR2M/edit?usp=sharing

--Lars.kurth 09:31, 30 July 2014 (UTC) Not sure I fully buy into the missing pieces (except for the network piece)

We have Xen_Overview and Getting_Started which cover some of what you are looking for. Admittedly these can be improved - in particular in light of articles such as

• http://www.brendangregg.com/blog/2014-05-07/what-color-is-your-xen.html
• http://www.brendangregg.com/blog/2014-05-09/xen-feature-detection.html
• http://www.informit.com/articles/article.aspx?p=2233978

And the sources for some of the diagrams in these can be downloaded from http://www.slideshare.net/xen_com_mgr/xen-hypervisor-for-the-cloud-frontier-meetup

--Rich.T. So, would this do for the guide?

That should work, unless you find a better one Rcpavlicek 17:42, 30 July 2014 (UTC)

Proposed Changes

 DaveHill (talk) (talk) 21:50, 6 October 2018 (UTC) I'm not sure how carefully changes to the wiki are reviewed before finalizing. I've been working through the Xen Project Beginners Guide and would make some changes which I would propose here first for comment.

The first one would be to correct an error in the section below on setting up xenbridge.

This file is very simple. Each stanza represents a single interface. Breaking it down “auto eth0” means that eth0 will be configured when ifup -a is run (which is run a boot time) what this means is that the interface will automatically be started/stopped for you. “iface eth0” then describes the interface itself, in this case it merely specifies that it should be configured by DHCP - we are going to assume that you have DHCP running on your network for this guide. If you are using static addressing you probably know how to set that up. We are going to edit this file so it resembles such:

    auto lo
    iface lo inet loopback

    auto eth0
    iface eth0 inet dhcp
    
    auto xenbr0
    iface xenbr0 inet dhcp
        bridge_ports eth0

 DaveHill (talk) (talk) 21:50, 6 October 2018 (UTC):The eth0 lines in the file are

   auto eth0
   iface eth0 inet dhcp

but should be

   auto eth0
   iface eth0 inet manual

(as per the Important Note! here:https://wiki.xenproject.org/wiki/Network_Configuration_Examples_(Xen_4.1%2B) and my own experience).

--Lars.kurth (talk) 14:43, 9 October 2018 (UTC) I fixed that, crediting you

 DaveHill (talk) (talk) 15:31, 12 October 2018 (UTC) Further Proposed Changes

General Description

First, let me say that the Guide is fantastic!!! It is well written and has gotten me through to a working hypervisor system several times with success (okay, maybe my 2010 laptop wasn’t quite up to virtualizing Windows in a sustainable fashion – not Xen’s fault!).

Having said that, the Guide seems to have been written a few years ago - Xen and Debian have moved along some way since then, and, like all documentation, it could use a general refresh from time to time.. I would do that as follows, subject to comments from wiser minds.

Throughout

Standardize to “dom0” and “domu” or “Dom0” and DomU” or “dom0” and “domU” (personally, I like the last but I’m a beginner :-).

Since the premise is that the user downloads and works with the current version of Debian: - take out references to obsolete Debian releases (Squeeze, Wheezy, etc) throughout - wherever possible, simply refer to “the current release” or make clear that “Stretch” stands in for that

Update package names and drop those no longer currently required (e.g. qemu which is now rolled in to xen-system-am64).

Make small typo/grammatical changes.

BIOS

Add suggestion that user dig around in BIOS to make sure both VT-x and VT-d or AMD-V and IOMMU are enabled if available.

Bridging

In xenbridge section, add alternatives to “eth0” like “enp2s0” etc.

GRUB in dom0

Remove the current suggestion to use dpkg-divert to change GRUB boot order in dom0. My installation at least (Debian 9) reliably defaults to booting Xen. (Even if it didn’t dpkg-divert seems a bit heavy handed to me – aren’t there are other ways to do this?)

Xen Commands

Remove references to xm. Add xl dmesg to see what's enabled. Consider moving Xen commands before Bridging and GRUB section so it follows BIOS changes.

Creating a PV Guest using xen-create-image

Add a section on pvgrub (and, in kind, other changes: replace –pygrub in the xen-create-image command line with –nopygrub, etc)

Creating a PV Guest Manually

The Alpine documentation needs updating – it assumes that pvgrub will boot with a grub menu.lst file which it no longer does. I plan to ask to edit . . . In the meantime, I would add a brief description of how to get around that here (or not – lower priority).

Creating an HVM Guest

Changes/additions to the config file – e.g. specify a VNC display for certainty, possibly add a section on using spice (I’m new to it).

Switch "Start GUI" section with "PV drivers" section

Switch the order of “Installing PV drivers for HVM guests” and “Starting a GUI guest (with VNC server)”

Starting a GUI guest (with VNC server)

Put in a few more details on using VNC (and maybe spice and/or sdl)

Installing PV drivers for HVM guests Change links to refer to Xen Project Windows PV drivers and installation instructions.

Pass-through

Finally, add a section on approaches to and further sources on PCI and USB pass-through.

Since I’m proposing what seems to me at least to be a fairly involved re-write, I’d appreciate any thoughts/comments. I wonder if there's a place I could prototype it in html for others to see, like Sandbox maybe?

--Lars.kurth (talk) 16:44, 1 November 2018 (UTC) Dave, I had not had time to deal with this yet. Was tied down with a number of things, such as Open Source Summit and working on a new website. I hopefully will get round to reviewing and modifying the content soon.

 DaveHill (talk) (talk) 15:35, 2 November 2018 (UTC):Thanks, Lars. Not having heard anything from anyone, I started editing the Guide along the lines outlined above. I've noted the sections I've changed, which aren't many so far.

I see you say that you hope to get around to reviewing and modifying soon. I'm not sure if you mean reviewing and modifying the changes I propose here on the talk page or if you mean editing the Guide itself? If the latter, I just want to be clear that I didn't mean to suggest that you make changes. I assume you're busy enough as is, and it's kind of not done to propose work expecting someone else to do it, I think. I was proposing to make the edits myself, as a way of contributing back. If you want to make the changes, though, I'm happy to leave it to you. Just let me know which. Thanks, Dave.

--Lars.kurth (talk) 17:09, 2 November 2018 (UTC)I thought you were expecting me or someone else to make the changes. I am quite happy for you to make changes and help out if needed. The changes you made look good. Thank you.

Thanks, Lars. Will do.