xl.conf(5)

1xl.conf(5)                            Xen                           xl.conf(5)
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NAME

6       /etc/xen/xl.conf - XL Global/Host Configuration
7

DESCRIPTION

9       The xl.conf file allows configuration of hostwide "xl" toolstack
10       options.
11
12       For details of per-domain configuration options please see xl.cfg(5).
13

SYNTAX

15       The config file consists of a series of "KEY=VALUE" pairs.
16
17       A value "VALUE" is one of:
18
19       "STRING"
20           A string, surrounded by either single or double quotes.
21
22       NUMBER
23           A number, in either decimal, octal (using a 0 prefix) or
24           hexadecimal (using an "0x" prefix).
25
26       BOOLEAN
27           A "NUMBER" interpreted as "False" (0) or "True" (any other value).
28
29       [ VALUE, VALUE, ... ]
30           A list of "VALUES" of the above types. Lists are homogeneous and
31           are not nested.
32
33       The semantics of each "KEY" defines which form of "VALUE" is required.
34

OPTIONS

36       domid_policy="xen"|"random"
37           Determines how domain-id is set when creating a new domain.
38
39           If set to "xen" then the hypervisor will allocate new domain-id
40           values on a sequential basis.
41
42           If set to "random" then a random domain-id value will be chosen.
43
44           Default: "xen"
45
46       autoballoon="off"|"on"|"auto"
47           If set to "on" then "xl" will automatically reduce the amount of
48           memory assigned to domain 0 in order to free memory for new
49           domains.
50
51           If set to "off" then "xl" will not automatically reduce the amount
52           of domain 0 memory.
53
54           If set to "auto" then auto-ballooning will be disabled if the
55           "dom0_mem" option was provided on the Xen command line.
56
57           You are strongly recommended to set this to "off" (or "auto") if
58           you use the "dom0_mem" hypervisor command line to reduce the amount
59           of memory given to domain 0 by default.
60
61           Default: "auto"
62
63       run_hotplug_scripts=BOOLEAN
64           If disabled hotplug scripts will be called from udev, as it used to
65           be in the previous releases. With the default option, hotplug
66           scripts will be launched by xl directly.
67
68           Default: 1
69
70       lockfile="PATH"
71           Sets the path to the lock file used by xl to serialise certain
72           operations (primarily domain creation).
73
74           Default: "/var/lock/xl"
75
76       max_grant_frames=NUMBER
77           Sets the default value for the "max_grant_frames" domain config
78           value.
79
80           Default: value of Xen command line gnttab_max_frames parameter (or
81           its default value if unspecified).
82
83       max_maptrack_frames=NUMBER
84           Sets the default value for the "max_maptrack_frames" domain config
85           value.
86
87           Default: value of Xen command line gnttab_max_maptrack_frames
88           parameter (or its default value if unspecified).
89
90       max_grant_version=NUMBER
91           Sets the default value for the "max_grant_version" domain config
92           value.
93
94           Default: maximum grant version supported by the hypervisor.
95
96       vif.default.script="PATH"
97           Configures the default hotplug script used by virtual network
98           devices.
99
100           The old vifscript option is deprecated and should not be used.
101
102           Default: "/etc/xen/scripts/vif-bridge"
103
104       vif.default.bridge="NAME"
105           Configures the default bridge to set for virtual network devices.
106
107           The old defaultbridge option is deprecated and should not be used.
108
109           Default: "xenbr0"
110
111       vif.default.backend="NAME"
112           Configures the default backend to set for virtual network devices.
113
114           Default: 0
115
116       vif.default.gatewaydev="NAME"
117           Configures the default gateway device to set for virtual network
118           devices.
119
120           Default: "None"
121
122       remus.default.netbufscript="PATH"
123           Configures the default script used by Remus to setup network
124           buffering.
125
126           Default: "/etc/xen/scripts/remus-netbuf-setup"
127
128       colo.default.proxyscript="PATH"
129           Configures the default script used by COLO to setup colo-proxy.
130
131           Default: "/etc/xen/scripts/colo-proxy-setup"
132
133       output_format="json|sxp"
134           Configures the default output format used by xl when printing
135           "machine readable" information. The default is to use the "JSON"
136           <https://www.json.org/> syntax. However for compatibility with the
137           previous "xm" toolstack this can be configured to use the old "SXP"
138           (S-Expression-like) syntax instead.
139
140           Default: "json"
141
142       blkdev_start="NAME"
143           Configures the name of the first block device to be used for
144           temporary block device allocations by the toolstack.  The default
145           choice is "xvda".
146
147       claim_mode=BOOLEAN
148           If this option is enabled then when a guest is created there will
149           be an guarantee that there is memory available for the guest.  The
150           self-balloon mechanism can deflate/inflate the balloon quickly and
151           the amount of free memory (which "xl info" can show) is stale the
152           moment it is printed. When claim is enabled a reservation for the
153           amount of memory (see 'memory' in xl.conf(5)) is set, which is then
154           reduced as the domain's memory is populated and eventually reaches
155           zero.  The free memory in "xl info" is the combination of the
156           hypervisor's free heap memory minus the outstanding claims value.
157
158           If the reservation cannot be meet the guest creation fails
159           immediately instead of taking seconds/minutes (depending on the
160           size of the guest) while the guest is populated.
161
162           Default: 1
163
164           0   No claim is made. Memory population during guest creation will
165               be attempted as normal and may fail due to memory exhaustion.
166
167           1   Free memory as reported by the hypervisor is used for
168               calculating whether there is enough memory free to launch a
169               guest.  This guarantees immediate feedback whether the guest
170               can be launched due to memory exhaustion (which can take a long
171               time to find out if launching massively huge guests).
172
173       vm.cpumask="CPULIST"
174       vm.hvm.cpumask="CPULIST"
175       vm.pv.cpumask="CPULIST"
176           Global masks that are applied when creating guests and pinning
177           vcpus to indicate which cpus they are allowed to run on.
178           Specifically, "vm.cpumask" applies to all guest types,
179           "vm.hvm.cpumask" applies to both HVM and PVH guests and
180           "vm.pv.cpumask" applies to PV guests.
181
182           The hard affinity of guest's vcpus are logical-AND'ed with
183           respective masks. If the resulting affinity mask is empty,
184           operation will fail.
185
186           Use --ignore-global-affinity-masks to skip applying global masks.
187
188           The default value for these masks are all 1's, i.e. all cpus are
189           allowed.
190
191           Due to bug(s), these options may not interact well with other
192           options concerning CPU affinity. One example is CPU pools. Users
193           should always double check that the required affinity has taken
194           effect.
195

NAME

DESCRIPTION

SYNTAX

OPTIONS

SEE ALSO