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| author | kaf24@freefall.cl.cam.ac.uk <kaf24@freefall.cl.cam.ac.uk> | 2004-10-26 14:12:48 +0000 |
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| committer | kaf24@freefall.cl.cam.ac.uk <kaf24@freefall.cl.cam.ac.uk> | 2004-10-26 14:12:48 +0000 |
| commit | cadf3eafb224880e277913a011a7e358517551a6 (patch) | |
| tree | 4479b17ef7e947d4eaea752adaeaff6cdf27c10e /docs/misc/xen_config.html | |
| parent | f1816bd031a1dd3e7927d88b3345b4fbb139ea11 (diff) | |
| download | xen-cadf3eafb224880e277913a011a7e358517551a6.tar.gz xen-cadf3eafb224880e277913a011a7e358517551a6.tar.bz2 xen-cadf3eafb224880e277913a011a7e358517551a6.zip | |
bitkeeper revision 1.1159.1.282 (417e5b60oXUOPTWl81d5zD6oq1tOTQ)
Clean up docs dir layout.
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diff --git a/docs/misc/xen_config.html b/docs/misc/xen_config.html new file mode 100644 index 0000000000..447ebeec53 --- /dev/null +++ b/docs/misc/xen_config.html @@ -0,0 +1,194 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> +<html> +<head> + <meta http-equiv="content-type" content="text/html; charset=ISO-8859-1"> + <title>Xen Configuration Syntax</title> +</head> +<body> +<center> +<h1>Xen Configuration Syntax</h1> +<br> +<!-- Version 0.1<br>2004 June 21<br> --> +Version 0.2<br>2004 July 19<br> +</center> + +<h1>Xen Configuration</h1> +The Xen virtual machine creation tools provide command-line interfaces and +HTTP interfaces to creating virtual machines. Underneath all these interfaces +virtual machine configuration data is represented in a common configuration syntax +called SXP. + +The SXP syntax is s-expressions (sxprs), a simple bracketed abstract syntax. +Python lists are used to represent its parsed form, with a support +api providing access to fields and values (class xen.xend.sxp). + +<h1>SXP syntax</h1> +<p>A general s-expression has the syntax: +<code><pre> +s-exp = '(' s-exp* ')' | atom | string +</pre></code> +Where an <code>atom</code> is an unquoted string, such as fred or /domain/0. +A <code>string</code> is a quoted string, supporting the usual escape sequences. +Strings support single or double quotes: 'fred 1' or "fred 2" are both accepted. +The characters ()[]<>{} are separators. + +<p>An <code>element</code> is an s-expression representing data similar to XML. +It has the form: +<code><pre> +element = '(' name attributes? value* ')' +name = atom +attributes = '(' '@' attribute* ')' +attribute = '(' attrname attrval ')' +attrname = atom +attrval = atom | string +value = element | atom | string +</pre></code> +The <code>name</code> is the element name (roughly indentifying its type). +The <code>attributes</code> is a list of attribute-values. +We usually prefer to avoid using attributes, and use sub-elements instead. +As in XML, any element may have the attribute <code>id</code> to give it an identifier +for later reference. + +<h1>VM configuration</h1> +A vm configuration is a single SXP vm element, with subelements for +vm parameters and devices. The supported elements and their fields +are listed below. + +<h2>(vm) element</h2> +The top-level element, a virtual machine configuration. +<ul> + <li>name: string, required. Domain name. + <li>id: int, optional, default generated. Domain unique id. + <li>memory: int, required. Domain memory in MB. + <li>maxmem: int, optional. Maximum domain memory in MB. + <li>cpu: int, optional. Cpu to run on. + <li>cpu_weight, float, optional, default 1. Cpu weight - controls share of CPU. + <li>image: linux | netbsd | ..., required. Domain image (OS-specific element). + <li>backend: any backend device type, optional, default none. + <li>device: any device type, optional, repeats. Device. + <li>restart: string, optional, default onreboot. Restart mode, one of + <ul><li>onreboot: restart the domain when it exits with code reboot. + <li>always: always restart the domain when it exits. + <li>never: never restart the domain. + </ul> + <li>console: int, optional, default 9600 + domain id. Console port. +</ul> + +<h2>(image (linux)) element</h2> +Defines a linux kernel image and its command-line parameters. +<ul> + <li>kernel: string, required. Kernel image file (absolute path). + <li>root: string, optional. Root device. + <li>ip: string, optional. IP address specifier. + <li>ramdisk: string, optional, default none. Ramdisk file (absolute path). + <li>args: string, optional. Extra kernel args. +</ul> + +<h2>(image (netbsd)) element</h2> +Defines a netbsd kernel image and its command-line parameters. +<ul> + <li>kernel: string, required. Kernel image file. + <li>root: string, optional. Root device. + <li>ip: string, optional. IP address specifier. + <li>ramdisk: string, optional, default none. Ramdisk file. + <li>args: string, optional. Extra kernel args. +</ul> + +<h2>(backend (blkif)) element</h2> +The vm is a block device backend. +The vm can have pci devices configured. + +<h2>(backend (netif)) element</h2> +The vm is a net device backend. + +<h2>(device (vif)) element</h2> +Defines a virtual network interface. +<ul> + <li>mac: string, required. Interface MAC address. + <li>bridge: string, optional, default system-dependent. Bridge to connect to. + <li>script: string, optional, default system-dependent. Vif script to use + when bringing the interface up or down. + <li>ip: IP address, optional, no default. May be repeated. An IP address + or CIDR-format subnet the vif may use. + <li>backend: domain name or id, optional, default 0. + Defines the domain to use as the backend for the interface. +</ul> + +<h2>(device (vbd)) element</h2> +Defines a virtual block device. +<ul> + <li>uname: string, required. Virtual block device id, e.g phys:hda1. + <li>dev: string, required. Device file name in domain, e.g. xda1. + <li>mode: string, optional, default r. Read-write mode: r | rw | w. + <li>backend: domain name or id, optional, default 0. + Defines the domain to use as the backend for the device. +</ul> +The uname field defines the device being exported from the block device +controller. The dev field defines the device name the vm will see. +The device is read-only unless the mode contains w. + +<h2>(device (pci)) element</h2> +Defines a pci device. +<ul> + <li>bus: int, required. PCI bus id. + <li>dev: int, required. PCI dev id. + <li>func: int, required. PCI func id. +</ul> +The bus, dev or func may be given in hex, +e.g. 0xff. With no leading 0x they are interpreted as decimal. + +<h2>(vnet) element</h2> +Defines the virtual networks associated with vifs (may go away soon). +Contains a list of vif elements: +<ul> + <li>id: id of the vif being configured. + <li>vnet: id of vnet the vif is assigned to. +</ul> + +<h1>Examples</h1> +<p> A vm with 64 MB memory, root on /dev/xda1 (mapped from /dev/hda1), +one vif with default MAC. +<code><pre> +(vm + (name xendom1) + (memory 64) + (image + (linux + (kernel /boot/vmlinuz-2.4.26-xen) + (ip ::::xendom1:eth0:dhcp) + (root /dev/xda1) + (args 'rw fastboot 4') + ) + ) + (device (vif)) + (device (vbd (uname phy:hda1) (dev xda1) (mode w))) +) +</pre></code> + +<p>A vm with 64 MB memory, NFS root, and 2 vifs on separate vnets. +<code><pre> +(vm + (name xendom2) + (memory 64) + # Define a linux image. + (image + (linux + (kernel "/boot/vmlinuz-2.4.26-xen") + (ip "::::xendom2:eth0:dhcp") + (root "/dev/nfs") + (args "rw fastboot nfsroot=15.144.25.79:/opt/xen/xendom2 4") + ) + ) + # Define some vifs, with ids for use later. + (device (vif (@ (id vif1)) (mac aa:00:00:00:00:12))) + (device (vif (@ (id vif2)) (mac aa:00:00:00:10:12))) + + # Configure vnets. Refer to vifs by id. + (vnet (vif (id vif1) (vnet 1)) + (vif (id vif2) (vnet 2))) + +) +</pre></code> + +</body> +</html> |