Learn_virsh_XML_configure_and_qemu-kvm_cmdline.

Learn_virsh_XML_configure_and_qemu-kvm_cmdline.

1.Attach a scsi-block/scsi-hd/scsi-cd/scsi-generic device.
1.1.scsi-block device.
e.g1:...-drive file=/dev/disk/by-path/ip-10.66.33.253:3260-iscsi-iqn.2014.sluo.com:iscsi.storage.1-lun-1,if=none,id=drive-scsi0-0-0-1,format=raw,cache=none -device scsi-block,bus=scsi0.0,channel=0,scsi-id=0,lun=1,drive=drive-scsi0-0-0-1,id=scsi0-0-0-1
...
    <disk type='block' device='lun' >
      <driver name='qemu' type='raw' cache='none'/>
      <source dev='/dev/disk/by-path/ip-10.66.33.253:3260-iscsi-iqn.2014.sluo.com:iscsi.storage.1-lun-1'/>
      <target dev='sdb' bus='scsi'/>
      <alias name='scsi0-0-0-1'/>
      <address type='drive' controller='0' bus='0' target='0' unit='1'/>
    </disk>
    <controller type='scsi' index='0' model='virtio-scsi'>
      <alias name='scsi0'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x07' function='0x0'/>
    </controller>
...

1.2.scsi-hd device.
e.g2:...-device virtio-scsi-pci,id=scsi0,bus=pci.0,addr=0x7 -drive file=/home/my-data-disk.raw,if=none,id=drive-scsi0-0-0-1,format=raw,cache=none -device scsi-hd,bus=scsi0.0,channel=0,scsi-id=0,lun=1,drive=drive-scsi0-0-0-1,id=scsi0-0-0-1 
...
    <disk type='file' device='disk' >
      <driver name='qemu' type='raw' cache='none'/>
      <source file='/home/my-data-disk.raw'/>
      <target dev='sdb' bus='scsi'/>
      <alias name='scsi0-0-0-1'/>
      <address type='drive' controller='0' bus='0' target='0' unit='1'/>
    </disk>
    <controller type='scsi' index='0' model='virtio-scsi'>
      <alias name='scsi0'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x07' function='0x0'/>
    </controller>
...

1.3.scsi-cd device.
e.g3:...-device virtio-scsi-pci,id=scsi0,bus=pci.0,addr=0x7 -drive file=/home/RHEL-7.0-20131030.1-Server-x86_64-dvd1.iso,if=none,id=drive-scsi0-0-0-1,readonly=on,format=raw,cache=none -device scsi-cd,bus=scsi0.0,channel=0,scsi-id=0,lun=1,drive=drive-scsi0-0-0-1,id=scsi0-0-0-1
...
    <disk type='file' device='cdrom' >
      <driver name='qemu' type='raw' cache='none'/>
      <source file='/home/RHEL-7.0-20131030.1-Server-x86_64-dvd1.iso'/>
      <target dev='hdb' bus='scsi'/>
      <alias name='scsi0-0-0-1'/>
      <address type='drive' controller='0' bus='0' target='0' unit='1'/>
    </disk>
    <controller type='scsi' index='0' model='virtio-scsi'>
      <alias name='scsi0'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x07' function='0x0'/>
    </controller>
...

1.4.scsi-generic device.
# sg_map | grep /dev/sdb
/dev/sg3  /dev/sdb
# virsh nodedev-list --tree
...
  +- scsi_host6
      |
      +- scsi_target6_0_0
          |
          +- scsi_6_0_0_0
          |   |
          |   +- scsi_generic_sg2
          |     
          +- scsi_6_0_0_1
              |
              +- block_sdb_1IET_00060001
              +- scsi_generic_sg3
...
e.g4:...-drive file=/dev/sg3,if=none,id=drive-hostdev0,readonly=on -device scsi-generic,bus=scsi0.0,channel=0,scsi-id=0,lun=0,drive=drive-hostdev0,id=hostdev0
...
    </controller>
    <hostdev mode='subsystem' type='scsi'>
      <source>
        <adapter name='scsi_host6'/>
        <address type='scsi' bus='0' target='0' unit='1'/>
      </source>
      <readonly/>
      <address type='drive' controller='0' bus='0' target='0' unit='0'/>
    </hostdev>
    <controller type='scsi' index='0' model='virtio-scsi'>
      <alias name='scsi0'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x07' function='0x0'/>
    </controller>
...

2.Attach a virtio-blk device.
e.g:...-drive file=/home/my-data-disk.raw,if=none,id=drive-virtio-disk0,format=raw -device virtio-blk-pci,scsi=off,bus=pci.0,addr=0x5,drive=drive-virtio-disk0,id=virtio-disk0
...
    <disk type='file' device='disk'>
      <driver name='qemu' type='raw'/>
      <source file='/home/my-data-disk.raw'/>
      <target dev='vda' bus='virtio'/>
      <alias name='virtio-disk0'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x05' function='0x0'/>
    </disk>
...

3.Attach a ide-cd/ide-hd device.
3.1.ide-hd device.
e.g1:...-drive file=/home/my-data-disk.raw,if=none,id=drive-ide0-0-1,format=raw,cache=none -device ide-hd,bus=ide.0,unit=1,drive=drive-ide0-0-1,id=ide0-0-1
...
    <disk type='file' device='disk'>
      <driver name='qemu' type='raw' cache='none'/>
      <source file='/home/my-data-disk.raw'/>
      <target dev='hdb' bus='ide'/>
      <address type='drive' controller='0' bus='0' target='0' unit='1'/>
    </disk>
    <controller type='ide' index='1'>
      <alias name='ide1'/>
    </controller> 
...
3.2.ide-cd device.
e.g2:...-drive file=/home/RHEL-7.0-20140507.0-Server-x86_64-dvd1.iso,if=none,id=drive-ide0-0-1,readonly=on,format=raw,cache=none -device ide-cd,bus=ide.0,unit=1,drive=drive-ide0-0-1,id=ide0-0-1
...
    <disk type='file' device='cdrom'>
      <driver name='qemu' type='raw' cache='none'/>
      <source file='/home/RHEL-7.0-20140507.0-Server-x86_64-dvd1.iso'/>
      <target dev='hdb' bus='ide'/>
      <address type='drive' controller='0' bus='0' target='0' unit='1'/>
    </disk>
    <controller type='ide' index='1'>
      <alias name='ide1'/>
    </controller> 
...

4.Attach a ahci-cd/ahci-hd device.
4.1.ahci-hd device.
e.g1:...-device ahci,id=ahci0,bus=pci.0,addr=0x5 -drive file=/home/my-data-disk.raw,if=none,id=drive-sata0-0-0,format=raw -device ide-hd,bus=ahci0.0,drive=drive-sata0-0-0,id=sata0-0-0
...
    <disk type='file' device='disk'>
      <driver name='qemu' type='raw'/>
      <source file='/home/my-data-disk.raw'/>
      <target dev='sdb' bus='sata'/>
      <alias name='ahci-disk0'/>
      <address type='drive' controller='0' bus='0' target='0' unit='0'/>
    </disk>
    <controller type='sata' index='0'>
      <alias name='sata0'/>
    </controller> 
...
4.2.ahci-cd device.
e.g2:...-device ahci,id=ahci0,bus=pci.0,addr=0x5 -drive file=/home/RHEL-7.0-20140507.0-Server-x86_64-dvd1.iso,if=none,media=cdrom,id=drive-sata0-0-0,readonly=on,format=raw -device ide-cd,bus=ahci0.0,drive=drive-sata0-0-0,id=sata0-0-0
...
    <disk type='file' device='cdrom'>
      <driver name='qemu' type='raw'/>
      <source file='/home/RHEL-7.0-20140507.0-Server-x86_64-dvd1.iso'/>
      <target dev='sdb' bus='sata'/>
      <alias name='ahci-disk0'/>
      <address type='drive' controller='0' bus='0' target='0' unit='0'/>
    </disk>
    <controller type='sata' index='0'>
      <alias name='sata0'/>
    </controller> 
...

5.Attach/Detach a raw format disk device from XML file to guest.
5.1.start a domain.
# virsh create scsi-block-testing.xml 
Domain scsi-block-testing created from scsi-block-testing.xml
5.2.create a disk desription file as following XML.
# cat disk-scsi-block.xml
    <disk type='block' device='lun' >
      <driver name='qemu' type='raw' cache='none'/>
      <source dev='/dev/disk/by-path/ip-10.66.33.253:3260-iscsi-iqn.2014.sluo.com:iscsi.storage.1-lun-1'/>
      <target dev='sdb' bus='scsi'/>
      <alias name='scsi0-0-0-1'/>
      <address type='drive' controller='0' bus='0' target='0' unit='1'/>
    </disk>
5.3.# virsh attach-device scsi-block-testing disk-scsi-block.xml
    Device attached successfully
5.4.# # virsh detach-disk scsi-block-testing sdb
    Disk detached successfully

6.Attach/Detach a raw format disk device to guest
6.1.start a domain.
# virsh create scsi-block-testing.xml 
Domain scsi-block-testing created from scsi-block-testing.xml
6.2.# virsh attach-disk scsi-block-testing /dev/disk/by-path/ip-10.66.33.253:3260-iscsi-iqn.2014.sluo.com:iscsi.storage.1-lun-1 sdb --type lun
    Disk attached successfully
6.3.# virsh detach-disk scsi-block-testing sdb
    Disk detached successfully

7.Migration with VM via virsh.
# virsh migrate --live $domain_name qemu+ssh://$dst_ip/system
migrate-setmaxdowntime set maximum tolerable downtime
migrate-compcache get/set compression cache size
migrate-setspeed Set the maximum migration bandwidth
migrate-getspeed Get the maximum migration bandwidth

8.Network device(rtl8139/e1000/virtio-net-pci).
e.g1:...-netdev tap,fd=23,id=hostnet0 -device virtio-net-pci,netdev=hostnet0,id=net0,mac=0a:01:38:b6:40:24,bus=pci.0,addr=0x3
...
    <interface type='network'>
      <mac address='0a:01:38:b6:40:24'/>
      <source network='default'/>
      <target dev='vnet0'/>
      <model type='virtio-net-pci'/>
      <alias name='net0'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/>
    </interface>
...