<?xml version="1.0" ?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title></title> <meta http-equiv="content-type" content="text/html; charset=utf-8" /> <link rev="made" href="mailto:root@localhost" /> </head> <body> <ul id="index"> <li><a href="#NAME">NAME</a></li> <li><a href="#DESCRIPTION">DESCRIPTION</a></li> <li><a href="#SYNTAX">SYNTAX</a></li> <li><a href="#OPTIONS">OPTIONS</a></li> <li><a href="#SEE-ALSO">SEE ALSO</a></li> </ul> <h1 id="NAME">NAME</h1> <p>/etc/xen/xl.conf - XL Global/Host Configuration</p> <h1 id="DESCRIPTION">DESCRIPTION</h1> <p>The <i>xl.conf</i> file allows configuration of hostwide <code>xl</code> toolstack options.</p> <p>For details of per-domain configuration options please see <a href="http://man.he.net/man5/xl.cfg">xl.cfg(5)</a>.</p> <h1 id="SYNTAX">SYNTAX</h1> <p>The config file consists of a series of <code>KEY=VALUE</code> pairs.</p> <p>A value <code>VALUE</code> is one of:</p> <dl> <dt id="STRING"><b>"STRING"</b></dt> <dd> <p>A string, surrounded by either single or double quotes.</p> </dd> <dt id="NUMBER"><b>NUMBER</b></dt> <dd> <p>A number, in either decimal, octal (using a <code>0</code> prefix) or hexadecimal (using an <code>0x</code> prefix).</p> </dd> <dt id="BOOLEAN"><b>BOOLEAN</b></dt> <dd> <p>A <code>NUMBER</code> interpreted as <code>False</code> (<code>0</code>) or <code>True</code> (any other value).</p> </dd> <dt id="VALUE-VALUE"><b>[ VALUE, VALUE, ... ]</b></dt> <dd> <p>A list of <code>VALUES</code> of the above types. Lists are homogeneous and are not nested.</p> </dd> </dl> <p>The semantics of each <code>KEY</code> defines which form of <code>VALUE</code> is required.</p> <h1 id="OPTIONS">OPTIONS</h1> <dl> <dt id="autoballoon-off-on-auto"><b>autoballoon="off"|"on"|"auto"</b></dt> <dd> <p>If set to "on" then <code>xl</code> will automatically reduce the amount of memory assigned to domain 0 in order to free memory for new domains.</p> <p>If set to "off" then <code>xl</code> will not automatically reduce the amount of domain 0 memory.</p> <p>If set to "auto" then auto-ballooning will be disabled if the <code>dom0_mem</code> option was provided on the Xen command line.</p> <p>You are strongly recommended to set this to <code>"off"</code> (or <code>"auto"</code>) if you use the <code>dom0_mem</code> hypervisor command line to reduce the amount of memory given to domain 0 by default.</p> <p>Default: <code>"auto"</code></p> </dd> <dt id="run_hotplug_scripts-BOOLEAN"><b>run_hotplug_scripts=BOOLEAN</b></dt> <dd> <p>If disabled hotplug scripts will be called from udev, as it used to be in the previous releases. With the default option, hotplug scripts will be launched by xl directly.</p> <p>Default: <code>1</code></p> </dd> <dt id="lockfile-PATH"><b>lockfile="PATH"</b></dt> <dd> <p>Sets the path to the lock file used by xl to serialise certain operations (primarily domain creation).</p> <p>Default: <code>/var/lock/xl</code></p> </dd> <dt id="vif.default.script-PATH"><b>vif.default.script="PATH"</b></dt> <dd> <p>Configures the default hotplug script used by virtual network devices.</p> <p>The old <b>vifscript</b> option is deprecated and should not be used.</p> <p>Default: <code>/etc/xen/scripts/vif-bridge</code></p> </dd> <dt id="vif.default.bridge-NAME"><b>vif.default.bridge="NAME"</b></dt> <dd> <p>Configures the default bridge to set for virtual network devices.</p> <p>The old <b>defaultbridge</b> option is deprecated and should not be used.</p> <p>Default: <code>xenbr0</code></p> </dd> <dt id="vif.default.backend-NAME"><b>vif.default.backend="NAME"</b></dt> <dd> <p>Configures the default backend to set for virtual network devices.</p> <p>Default: <code>0</code></p> </dd> <dt id="vif.default.gatewaydev-NAME"><b>vif.default.gatewaydev="NAME"</b></dt> <dd> <p>Configures the default gateway device to set for virtual network devices.</p> <p>Default: <code>None</code></p> </dd> <dt id="remus.default.netbufscript-PATH"><b>remus.default.netbufscript="PATH"</b></dt> <dd> <p>Configures the default script used by Remus to setup network buffering.</p> <p>Default: <code>/etc/xen/scripts/remus-netbuf-setup</code></p> </dd> <dt id="output_format-json-sxp"><b>output_format="json|sxp"</b></dt> <dd> <p>Configures the default output format used by xl when printing "machine readable" information. The default is to use the <code>JSON</code> <a href="http://www.json.org/">http://www.json.org/</a> syntax. However for compatibility with the previous <code>xm</code> toolstack this can be configured to use the old <code>SXP</code> (S-Expression-like) syntax instead.</p> <p>Default: <code>json</code></p> </dd> <dt id="blkdev_start-NAME"><b>blkdev_start="NAME"</b></dt> <dd> <p>Configures the name of the first block device to be used for temporary block device allocations by the toolstack. The default choice is "xvda".</p> </dd> <dt id="claim_mode-BOOLEAN"><b>claim_mode=BOOLEAN</b></dt> <dd> <p>If this option is enabled then when a guest is created there will be an guarantee that there is memory available for the guest. This is an particularly acute problem on hosts with memory over-provisioned guests that use tmem and have self-balloon enabled (which is the default option). The self-balloon mechanism can deflate/inflate the balloon quickly and the amount of free memory (which <code>xl info</code> can show) is stale the moment it is printed. When claim is enabled a reservation for the amount of memory (see 'memory' in xl.conf(5)) is set, which is then reduced as the domain's memory is populated and eventually reaches zero. The free memory in <code>xl info</code> is the combination of the hypervisor's free heap memory minus the outstanding claims value.</p> <p>If the reservation cannot be meet the guest creation fails immediately instead of taking seconds/minutes (depending on the size of the guest) while the guest is populated.</p> <p>Note that to enable tmem type guests, one needs to provide <code>tmem</code> on the Xen hypervisor argument and as well on the Linux kernel command line.</p> <p>Note that the claim call is not attempted if <code>superpages</code> option is used in the guest config (see xl.cfg(5)).</p> <p>Default: <code>1</code></p> <dl> <dt id="pod0"><code>0</code></dt> <dd> <p>No claim is made. Memory population during guest creation will be attempted as normal and may fail due to memory exhaustion.</p> </dd> <dt id="pod1"><code>1</code></dt> <dd> <p>Normal memory and freeable pool of ephemeral pages (tmem) is used when calculating whether there is enough memory free to launch a guest. This guarantees immediate feedback whether the guest can be launched due to memory exhaustion (which can take a long time to find out if launching massively huge guests).</p> </dd> </dl> </dd> </dl> <h1 id="SEE-ALSO">SEE ALSO</h1> <dl> <dt id="xl-1"><a href="http://man.he.net/man1/xl">xl(1)</a></dt> <dd> </dd> <dt id="xl.cfg-5"><a href="http://man.he.net/man5/xl.cfg">xl.cfg(5)</a></dt> <dd> </dd> <dt id="http:-www.json.org">http://www.json.org/</dt> <dd> </dd> </dl> </body> </html>