libvirt virsh domain命令解析(一)

怼烎@ 2023-06-16 10:36 24阅读 0赞

virsh是libvirt提供的命令行工具， 了解virsh命令的功能，可以快速了解libvirt的主要功能及功能特性

这里首先介绍domain  
domain 域， 可以看做是一个虚拟机实例

通过 `virsh -h` 可以查看所有命令， 能够看到每个命令的介绍信息（这里不做一一翻译）

# virsh -h
    
    virsh [options]... [<command_string>]
    virsh [options]... <command> [args...]
    
      options:
        -c | --connect=URI      hypervisor connection URI
        -d | --debug=NUM        debug level [0-4]
        -e | --escape <char>    set escape sequence for console
        -h | --help             this help
        -k | --keepalive-interval=NUM
                                keepalive interval in seconds, 0 for disable
        -K | --keepalive-count=NUM
                                number of possible missed keepalive messages
        -l | --log=FILE         output logging to file
        -q | --quiet            quiet mode
        -r | --readonly         connect readonly
        -t | --timing           print timing information
        -v                      short version
        -V                      long version
             --version[=TYPE]   version, TYPE is short or long (default short)
      commands (non interactive mode):

domain 域， 可看做一个虚拟机实例  
基础命令：

Domain Management (help keyword 'domain')
        attach-device                  attach device from an XML file
        attach-disk                    attach disk device
        attach-interface               attach network interface
        autostart                      autostart a domain
        blkdeviotune                   Set or query a block device I/O tuning parameters.
        blkiotune                      Get or set blkio parameters
        blockcommit                    Start a block commit operation.
        blockcopy                      Start a block copy operation.
        blockjob                       Manage active block operations
        blockpull                      Populate a disk from its backing image.
        blockresize                    Resize block device of domain.
        change-media                   Change media of CD or floppy drive
        console                        connect to the guest console
        cpu-stats                      show domain cpu statistics
        create                         create a domain from an XML file
        define                         define (but don't start) a domain from an XML file
        desc                           show or set domain's description or title
        destroy                        destroy (stop) a domain
        detach-device                  detach device from an XML file
        detach-device-alias            detach device from an alias
        detach-disk                    detach disk device
        detach-interface               detach network interface
        domdisplay                     domain display connection URI
        domfsfreeze                    Freeze domain's mounted filesystems.
        domfsthaw                      Thaw domain's mounted filesystems.
        domfsinfo                      Get information of domain's mounted filesystems.
        domfstrim                      Invoke fstrim on domain's mounted filesystems.
        domhostname                    print the domain's hostname
        domid                          convert a domain name or UUID to domain id
        domif-setlink                  set link state of a virtual interface
        domiftune                      get/set parameters of a virtual interface
        domjobabort                    abort active domain job
        domjobinfo                     domain job information
        domname                        convert a domain id or UUID to domain name
        domrename                      rename a domain
        dompmsuspend                   suspend a domain gracefully using power management functions
        dompmwakeup                    wakeup a domain from pmsuspended state
        domuuid                        convert a domain name or id to domain UUID
        domxml-from-native             Convert native config to domain XML
        domxml-to-native               Convert domain XML to native config
        dump                           dump the core of a domain to a file for analysis
        dumpxml                        domain information in XML
        edit                           edit XML configuration for a domain
        event                          Domain Events
        inject-nmi                     Inject NMI to the guest
        iothreadinfo                   view domain IOThreads
        iothreadpin                    control domain IOThread affinity
        iothreadadd                    add an IOThread to the guest domain
        iothreaddel                    delete an IOThread from the guest domain
        send-key                       Send keycodes to the guest
        send-process-signal            Send signals to processes
        lxc-enter-namespace            LXC Guest Enter Namespace
        managedsave                    managed save of a domain state
        managedsave-remove             Remove managed save of a domain
        managedsave-edit               edit XML for a domain's managed save state file
        managedsave-dumpxml            Domain information of managed save state file in XML
        managedsave-define             redefine the XML for a domain's managed save state file
        memtune                        Get or set memory parameters
        perf                           Get or set perf event
        metadata                       show or set domain's custom XML metadata
        migrate                        migrate domain to another host
        migrate-setmaxdowntime         set maximum tolerable downtime
        migrate-getmaxdowntime         get maximum tolerable downtime
        migrate-compcache              get/set compression cache size
        migrate-setspeed               Set the maximum migration bandwidth
        migrate-getspeed               Get the maximum migration bandwidth
        migrate-postcopy               Switch running migration from pre-copy to post-copy
        numatune                       Get or set numa parameters
        qemu-attach                    QEMU Attach
        qemu-monitor-command           QEMU Monitor Command
        qemu-monitor-event             QEMU Monitor Events
        qemu-agent-command             QEMU Guest Agent Command
        reboot                         reboot a domain
        reset                          reset a domain
        restore                        restore a domain from a saved state in a file
        resume                         resume a domain
        save                           save a domain state to a file
        save-image-define              redefine the XML for a domain's saved state file
        save-image-dumpxml             saved state domain information in XML
        save-image-edit                edit XML for a domain's saved state file
        schedinfo                      show/set scheduler parameters
        screenshot                     take a screenshot of a current domain console and store it into a file
        set-lifecycle-action           change lifecycle actions
        set-user-password              set the user password inside the domain
        setmaxmem                      change maximum memory limit
        setmem                         change memory allocation
        setvcpus                       change number of virtual CPUs
        shutdown                       gracefully shutdown a domain
        start                          start a (previously defined) inactive domain
        suspend                        suspend a domain
        ttyconsole                     tty console
        undefine                       undefine a domain
        update-device                  update device from an XML file
        vcpucount                      domain vcpu counts
        vcpuinfo                       detailed domain vcpu information
        vcpupin                        control or query domain vcpu affinity
        emulatorpin                    control or query domain emulator affinity
        vncdisplay                     vnc display
        guestvcpus                     query or modify state of vcpu in the guest (via agent)
        setvcpu                        attach/detach vcpu or groups of threads
        domblkthreshold                set the threshold for block-threshold event for a given block device or it's backing chain element

使用示例：  
设备的参数配置信息

# virsh blkiotune 12
    weight         : 500
    device_weight  : 
    device_read_iops_sec: 
    device_write_iops_sec: 
    device_read_bytes_sec: 
    device_write_bytes_sec:

# virsh help blkiotune 
      NAME
        blkiotune - Get or set blkio parameters
    
      SYNOPSIS
        blkiotune <domain> [--weight <number>] [--device-weights <string>] [--device-read-iops-sec <string>] [--device-write-iops-sec <string>] [--device-read-bytes-sec <string>] [--device-write-bytes-sec <string>] [--config] [--live] [--current]
    
      DESCRIPTION
        Get or set the current blkio parameters for a guest domain.
        To get the blkio parameters use following command: 
    
        virsh # blkiotune <domain>
    
      OPTIONS
        [--domain] <string>  domain name, id or uuid
        --weight <number>  IO Weight
        --device-weights <string>  per-device IO Weights, in the form of /path/to/device,weight,...
        --device-read-iops-sec <string>  per-device read I/O limit per second, in the form of /path/to/device,read_iops_sec,...
        --device-write-iops-sec <string>  per-device write I/O limit per second, in the form of /path/to/device,write_iops_sec,...
        --device-read-bytes-sec <string>  per-device bytes read per second, in the form of /path/to/device,read_bytes_sec,...
        --device-write-bytes-sec <string>  per-device bytes wrote per second, in the form of /path/to/device,write_bytes_sec,...
        --config         affect next boot
        --live           affect running domain
        --current        affect current domain

调整weight， config保存到config文件， live在线

# virsh blkiotune 12 --weight 1000 
    
    # virsh blkiotune 12
    weight         : 1000
    device_weight  : 
    device_read_iops_sec:

对于cpu使用信息， 保留cpu使用为0

# virsh cpu-stats 12
    CPU0:
            cpu_time             0.000000000 seconds
            vcpu_time            0.000000000 seconds
    CPU1:
            cpu_time             0.000000000 seconds
            vcpu_time            0.000000000 seconds
    CPU2:
            cpu_time           550.221846438 seconds
            vcpu_time          490.629911277 seconds
    CPU3:
            cpu_time           772.711305482 seconds
            vcpu_time          715.486739217 seconds

描述信息

# virsh desc 12
    No description for domain: instance-00000019

获取numa信息

# virsh numatune 12
    numa_mode      : strict
    numa_nodeset   :

虚拟机设置密码

# virsh help set-user-password
      NAME
        set-user-password - set the user password inside the domain
    
      SYNOPSIS
        set-user-password <domain> <user> <password> [--encrypted]
    
      DESCRIPTION
        changes the password of the specified user inside the domain
    
      OPTIONS
        [--domain] <string>  domain name, id or uuid
        [--user] <string>  the username
        [--password] <string>  the new password
        --encrypted      the password is already encrypted

设置内存

virsh setmem

设置cpu

virsh setvcpus