From: Stefano Stabellini Date: Tue, 1 Nov 2011 18:44:34 +0000 (+0000) Subject: docs: introduce an xl man page in pod format X-Git-Url: https://dgit.raspbian.org/?a=commitdiff_plain;h=5c7aad52472a2e89e593e8d8b3883a3600cd446f;p=xen.git docs: introduce an xl man page in pod format This is the initial version of an xl man page, based on the old xm man page. Almost every command implemented in xl should be present, a notable exception are the tmem commands that are currently missing. Further improvements and clarifications to this man page are very welcome. Signed-off-by: Stefano Stabellini Acked-by: Ian Jackson Committed-by: Ian Jackson --- diff --git a/docs/man/xl.pod.1 b/docs/man/xl.pod.1 new file mode 100644 index 0000000000..c0e66b9783 --- /dev/null +++ b/docs/man/xl.pod.1 @@ -0,0 +1,805 @@ +=head1 NAME + +XL - Xen management tool, based on LibXenlight + +=head1 SYNOPSIS + +B I [I] + +=head1 DESCRIPTION + +The B program is the new tool 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 old B tool is deprecated and should not be used. + +The basic structure of every B command is almost always: + +=over 2 + +B I [I] I + +=back + +Where I is one of the subcommands listed below, I +is the numeric domain id, or the domain name (which will be internally +translated to domain id), and I are subcommand specific +options. There are a few exceptions to this rule in the cases where +the subcommand in question acts on all domains, the entire machine, +or directly on the Xen hypervisor. Those exceptions will be clear for +each of those subcommands. + +=head1 NOTES + +Most B operations rely upon B and B: make +sure you start the script B at boot time to +initialize all the daemons needed by B. + +In the most common network configuration, you need to setup a bridge in dom0 +named B in order to have a working network in the guest domains. +Please refer to the documentation of your Linux distribution to know how to +setup the bridge. + +Most B commands require root privileges to run due to the +communications channels used to talk to the hypervisor. Running as +non root will return an error. + +=head1 DOMAIN SUBCOMMANDS + +The following subcommands manipulate domains directly. As stated +previously, most commands take I as the first parameter. + +=over 4 + +=item B [I] I + +The create subcommand requires a config file: see L for +full details of that file format and possible options. + +I can either be an absolute path to a file, or a relative +path to a file located in /etc/xen. + +Create will return B as the domain is started. This B mean the guest OS in the domain has actually booted, or is +available for input. + +B + +=over 4 + +=item B<-q>, B<--quiet> + +No console output. + +=item B<-f=FILE>, B<--defconfig=FILE> + +Use the given configuration file. + +=item B<-n>, B<--dryrun> + +Dry run - prints the resulting configuration in SXP but does not create +the domain. + +=item B<-p> + +Leave the domain paused after it is created. + +=item B<-c> + +Attach console to the domain as soon as it has started. This is +useful for determining issues with crashing domains. + +=back + +B + +=over 4 + +=item I + + xl create DebianLenny + +This creates a domain with the file /etc/xen/DebianLenny, and returns as +soon as it is run. + +=back + +=item B I + +Attach to domain I's console. If you've set up your domains to +have a traditional log in console this will look much like a normal +text log in screen. + +Use the key combination Ctrl+] to detach the domain console. + +=item B [I] I + +Attach to domain's VNC server, forking a vncviewer process. + +B + +=over 4 + +=item I<--autopass> + +Pass VNC password to vncviewer via stdin. + +=back + +=item B I + +Immediately terminate the domain I. This doesn't give the +domain OS any chance to react, and is the equivalent of ripping the +power cord out on a physical machine. In most cases you will want to +use the B command instead. + +=item B I + +Converts a domain name to a domain id. + +=item B I + +Converts a domain id to a domain name. + +=item B I I + +Change the domain name of I to I. + +=item B I [I] + +Dumps the virtual machine's memory for the specified domain to the +I specified, without pausing the domain. The dump file will +be written to a distribution specific directory for dump files. Such +as: /var/lib/xen/dump or /var/xen/dump. + +=item B [I<--long>] + +Displays the short help message (i.e. common commands). + +The I<--long> option prints out the complete set of B subcommands, +grouped by function. + +=item B [I] [I ...] + +Prints information about one or more domains. If no domains are +specified it prints out information about all domains. + + +B + +=over 4 + +=item B<-l>, B<--long> + +The output for B is not the table view shown below, but +instead presents the data in SXP compatible format. + +=item B<-Z>, B<--context> +Also prints the security labels. + +=item B<-v>, B<--verbose> + +Also prints the domain UUIDs, the shutdown reason and security labels. + +=back + +B + +An example format for the list is as follows: + + Name ID Mem VCPUs State Time(s) + Domain-0 0 750 4 r----- 11794.3 + win 1 1019 1 r----- 0.3 + linux 2 2048 2 r----- 5624.2 + +Name is the name of the domain. ID the numeric domain id. Mem is the +desired amount of memory to allocate to the domain (although it may +not be the currently allocated amount). VCPUs is the number of +virtual CPUs allocated to the domain. State is the run state (see +below). Time is the total run time of the domain as accounted for by +Xen. + +B + +The State field lists 6 states for a Xen domain, and which ones the +current domain is in. + +=over 4 + +=item B + +The domain is currently running on a CPU. + +=item B + +The domain is blocked, and not running or runnable. This can be caused +because the domain is waiting on IO (a traditional wait state) or has +gone to sleep because there was nothing else for it to do. + +=item B

+ +The domain has been paused, usually occurring through the administrator +running B. When in a paused state the domain will still +consume allocated resources like memory, but will not be eligible for +scheduling by the Xen hypervisor. + +=item B + +FIXME: Why would you ever see this state? + +=item B + +The domain has crashed, which is always a violent ending. Usually +this state can only occur if the domain has been configured not to +restart on crash. See L for more info. + +=item B + +The domain is in process of dying, but hasn't completely shutdown or +crashed. + +FIXME: Is this right? + +=back + +B + +=over 4 + +The Time column is deceptive. Virtual IO (network and block devices) +used by domains requires coordination by Domain0, which means that +Domain0 is actually charged for much of the time that a DomainU is +doing IO. Use of this time value to determine relative utilizations +by domains is thus very suspect, as a high IO workload may show as +less utilized than a high CPU workload. Consider yourself warned. + +=back + +=item B I I + +Specify the maximum amount of memory the domain is able to use, appending 't' +for terabytes, 'g' for gigabytes, 'm' for megabytes, 'k' for kilobytes and 'b' +for bytes. + +The mem-max value may not correspond to the actual memory used in the +domain, as it may balloon down its memory to give more back to the OS. + +=item B I I + +Set the domain's used memory using the balloon driver; append 't' for +terabytes, 'g' for gigabytes, 'm' for megabytes, 'k' for kilobytes and 'b' for +bytes. + +Because this operation requires cooperation from the domain operating +system, there is no guarantee that it will succeed. This command will +definitely not work unless the domain has the required paravirt +driver. + +B There is no good way to know in advance how small of a +mem-set will make a domain unstable and cause it to crash. Be very +careful when using this command on running domains. + +=item B [I] I I + +Migrate a domain to another host machine. By default B relies on ssh as a +transport mechanism between the two hosts. + +B + +=over 4 + +=item B<-s> I + +Use instead of ssh. String will be passed to sh. If empty, run + instead of ssh xl migrate-receive [-d -e]. + +=item B<-e> + +On the new host, do not wait in the background (on ) for the death of the +domain. + +=item B<-C> I + +Send instead of config file from creation. + +=back + +=item B I + +Pause a domain. When in a paused state the domain will still consume +allocated resources such as memory, but will not be eligible for +scheduling by the Xen hypervisor. + +=item B [I] I + +Reboot a domain. This acts just as if the domain had the B +command run from the console. The command returns as soon as it has +executed the reboot action, which may be significantly before the +domain actually reboots. + +The behavior of what happens to a domain when it reboots is set by the +B parameter of the xldomain.cfg file when the domain was +created. + +=item B [I] [I] I + +Build a domain from an B state file. See B for more info. + +B + +=over 4 + +=item B<-p> + +Do not unpause domain after restoring it. + +=item B<-e> + +Do not wait in the background for the death of the domain on the new host. + +=item B<-d> + +Enable debug messages. + +=back + +=item B [I] I I [I] + +Saves a running domain to a state file so that it can be restored +later. Once saved, the domain will no longer be running on the +system, unless the -c option is used. +B restores from this checkpoint file. +Passing a config file argument allows the user to manually select the VM config +file used to create the domain. + + +=over 4 + +=item B<-c> + +Leave domain running after creating the snapshot. + +=back + + +=item B [I] I + +Gracefully shuts down a domain. This coordinates with the domain OS +to perform graceful shutdown, so there is no guarantee that it will +succeed, and may take a variable length of time depending on what +services must be shutdown in the domain. The command returns +immediately after signally the domain unless that B<-w> flag is used. + +The behavior of what happens to a domain when it reboots is set by the +B parameter of the xldomain.cfg file when the domain was +created. + +B + +=over 4 + +=item B<-w> + +Wait for the domain to complete shutdown before returning. + +=back + +=item B I I + +Send a I signal to the domain. For more +information on available magic sys req operations, see sysrq.txt in +your Linux Kernel sources. + +=item B I + +Moves a domain out of the paused state. This will allow a previously +paused domain to now be eligible for scheduling by the Xen hypervisor. + +=item B I I + +Enables the I virtual CPUs for the domain in question. +Like mem-set, this command can only allocate up to the maximum virtual +CPU count configured at boot for the domain. + +If the I is smaller than the current number of active +VCPUs, the highest number VCPUs will be hotplug removed. This may be +important for pinning purposes. + +Attempting to set the VCPUs to a number larger than the initially +configured VCPU count is an error. Trying to set VCPUs to < 1 will be +quietly ignored. + +Because this operation requires cooperation from the domain operating +system, there is no guarantee that it will succeed. This command will +not work with a full virt domain. + +=item B [I] + +Lists VCPU information for a specific domain. If no domain is +specified, VCPU information for all domains will be provided. + +=item B I I I + +Pins the VCPU to only run on the specific CPUs. The keyword +B can be used to apply the I list to all VCPUs in the +domain. + +Normally VCPUs can float between available CPUs whenever Xen deems a +different run state is appropriate. Pinning can be used to restrict +this, by ensuring certain VCPUs can only run on certain physical +CPUs. + +=item B I I