view docs/man/xm.pod.1 @ 7698:37ad91483bd3

Increase the static constant default number of loopback interfaces, nloopbacks,
to 8. These interfaces are very cheap, so there's no problem having a few
spare. Anyone with more than 8 NICs can still use the kernel command line or
the module parameter line to pass a larger limit to this module.

Detail the kernel command line parameter for nloopbacks in the diagnostic in

Closes bug #381.

Signed-off-by: Ewan Mellor <>
date Tue Nov 08 15:15:02 2005 +0100 (2005-11-08)
parents d49fd494963e
children 55af8b55abd8
line source
1 =head1 NAME
3 xm - Xen management user interface
5 =head1 SYNOPSIS
7 xm <subcommand> [args]
11 The B<xm> program is the main interface for managing Xen guest domains. The program can be used to create, pause, and shutdown domains. It can also be used to list current domains, enable or pin VCPUs, and attach or detach virtual block devices. The B<xm> program relies upon B<xend>. The daemon must be running in order for the program to work.
13 Domain name <DomName> can be substituted in the subcommands for Domain id <DomId>.
17 =over 4
19 =item I<console> <DomId>
21 Attach to domain DomId's console.
23 =item I<create> <CfgFile>
25 Create a domain based on B<xmdomain.cfg> configuration file.
27 =item I<destroy> <DomId>
29 Terminate domain DomId immediately.
31 =item I<domid> <DomName>
33 Converts a domain name to a domain id.
35 =item I<domname> <DomId>
37 Converts a domain id to a domain name.
39 =item I<help> [--long]
41 Displays command's help message. The long option prints out the complete set of B<xm> subcommands.
43 =item I<list> [DomId, ...]
45 List information about domains.
47 =item I<mem-max> <DomId> <Mem>
49 Set domain maximum memory limit to Mem. Mem is in Megabytes. This is the upper memory mark for how much memory a domain can have.
51 =item I<mem-set> <DomId> <Mem>
53 Set domain's memory, in Megabytes. Mem must be less than or equal to the maximum memory for the domain.
55 =item I<migrate> <DomId> <Host> [Options]
57 Migrate a domain to another Host machine. B<Xend> must be running on other host machine and there must be sufficient resources as well.
59 =over 4
61 Additional Options:
63 -l, --live Use live migration.
64 -r, --resource <Mbit value> Set resource level.
66 =back
68 =item I<pause> <DomId>
70 Pause a domain's execution.
72 =item I<reboot> [Options] <DomId>
74 Reboot a domain.
76 =over 4
78 Additional Options:
80 -a, --all reboot all domains.
81 -w, --wait Wait for shutdown to complete.
83 =back
85 =item I<restore> <File>
87 Create a domain from saved state File.
89 =item I<save> <DomId> <File>
91 Save domain state to File. Saves domain configuration to File as well.
93 =item I<shutdown> [Options] <DomId>
95 Shutdown a domain.
97 =over 4
99 Additional Options:
101 -a, --all Shutdown all domains.
102 -H, --halt Shutdown domain without reboot.
103 -R, --reboot Shutdown and reboot domain.
104 -w, --wait Wait for shutdown to complete.
106 =back
108 =item I<sysrq> <DomId> <letter>
110 Send a sysrq to a domain.
112 =item I<unpause> <DomId>
114 Unpause a paused domain.
116 =item I<set-vcpus> <DomId> <VCPUs>
118 Enable a specific number of VCPUs for a domain. Subcommand only enables or disables already configured VCPUs for domain.
120 =item I<vpcu-list> [DomID]
122 Lists VCPU information for a specific domain or all domains if DomID not given.
124 =item I<vcpu-pin> <DomId> <VCPU> <CPUs>
126 Sets VCPU to only run on specific CPUs.
128 =back
132 =over 4
134 =item I<dmesg> [OPTION]
136 Read or clear Xen's message buffer. The buffer contains Xen boot, warning, and error messages.
138 =over 4
140 Additional Option:
142 -c, --clear Clears Xen's message buffer.
144 =back
146 =item I<info>
148 Get information about Xen host.
150 =item I<log>
152 Print B<xend> log.
154 =item I<top>
156 Monitor system and domains in real-time.
158 =back
162 =over 4
164 =item I<sched-bvt> <Parameters>
166 Set Borrowed Virtual Time (BVT) scheduler parameters. There are five parameters, which are given in order below.
168 =over 4
170 Parameters:
172 mcuadv - Minimum Charging Unit (MCU) advance.
173 warpback - Warp back time allowed.
174 warpvalue - Warp value.
175 warpl - Warp maximum limit.
176 warpu - Unwarped minimum limit.
178 =back
180 =item I<sched-bvt-ctxallow> <Allow>
182 Sets the BVT scheduler's context switch allowance. Allow is the minimum time slice allowed to run before being pre-empted.
184 =item I<sched-sedf> <Parameters>
186 Set simple sEDF scheduler parameters. Use the following parametersin order.
188 =over 4
190 Parameters:
192 period - in nanoseconds
193 slice - in nanoseconds
194 latency-hint - scaled period if domain is doing heavy I/O
195 extratime - flag for allowing domain to run in extra time.
196 weight - another way of setting cpu slice.
198 =back
200 =back
204 =over 4
206 =item I<block-attach <DomId> <BackDev> <FrontDev> <Mode> [BackDomId]
208 Create a new virtual block device.
210 =item I<block-detach> <DomId> <DevId>
212 Destroy a domain's virtual block device. DevId may either be a device ID or the device name as mounted in the guest.
214 =item I<block-list> <DomId>
216 List virtual block devices for a domain.
218 =item I<network-limit> <DomId> <Vif> <Credit> <Period>
220 Limit the transmission rate of a virtual network interface.
222 =item I<network-list> <DomId>
224 List virtual network interfaces for a domain.
226 =back
228 =head1 VNET COMMANDS
230 =over 4
232 =item I<vnet-list> [-l|--long]
234 List vnets.
236 =item I<vnet-create> <config>
238 Create a vnet from a config file.
240 =item I<vnet-delete> <vnetid>
242 Delete a vnet.
244 =back
246 =head1 SEE ALSO
248 B<xmdomain.cfg>(5)
250 =head1 AUTHOR
252 Daniel Stekloff <dsteklof at us dot ibm dot com>
254 =head1 BUGS