Installing Native Xen and KVM Drivers

Take CentOS 7.0 as an example. Modify the /etc/dracut.conf file. Add the Xen PV and VirtIO drivers to add_drivers. Xen PV drivers include xen-blkfront and xen-netfront. VirtIO drivers include virtio_blk, virtio_scsi, virtio_net, virtio_pci, virtio_ring, and virtio. Separate driver names with spaces. Save and exit the /etc/dracut.conf file. Run the dracut -f command to regenerate initrd.

For details, see CentOS and EulerOS.

Modify the /etc/initramfs-tools/modules file. Add the Xen PV and VirtIO drivers. Xen PV drivers include xen-blkfront and xen-netfront. VirtIO drivers include virtio_blk, virtio_scsi, virtio_net, virtio_pci, virtio_ring, and virtio. Separate driver names with spaces. Save and exit the /etc/initramfs-tools/modules file. Run the update-initramfs -u command to regenerate initrd.

For details, see Ubuntu and Debian.

• If the OS version is earlier than SUSE 12 SP1 or openSUSE 13, modify the /etc/sysconfig/kernel file and add Xen PV and VirtIO drivers to INITRD_MODULES="". Xen PV drivers include xen_vnif, xen_vbd, and xen_platform_pci. VirtIO drivers include virtio_blk, virtio_scsi, virtio_net, virtio_pci, virtio_ring, and virtio. Separate driver names with spaces. Run the mkinitrd command to regenerate initrd.
• If the OS version is SUSE 12 SP1, modify the /etc/dracut.conf file and add Xen PV and VirtIO drivers to add_drivers. Xen PV drivers include xen_vnif, xen_vbd, and xen_platform_pci. VirtIO drivers include virtio_blk, virtio_scsi, virtio_net, virtio_pci, virtio_ring, and virtio. Separate driver names with spaces. Run the dracut -f command to regenerate initrd.
• If the OS version is later than SUSE 12 SP1 or openSUSE 13, modify the /etc/dracut.conf file and add Xen PV and VirtIO drivers to add_drivers. Xen PV drivers include xen-blkfront and xen-netfront. VirtIO drivers include virtio_blk, virtio_scsi, virtio_net, virtio_pci, virtio_ring, and virtio. Separate driver names with spaces. Save and exit the /etc/dracut.conf file. Run the dracut -f command to regenerate initrd.

For details, see SUSE and openSUSE.

For SUSE, run the following command to check whether xen-kmp (driver package for Xen PV) is installed:

rpm -qa |grep xen-kmp

If information similar to the following is displayed, xen-kmp is installed in the OS:

xen-kmp-default-4.2.2_04_3.0.76_0.11-0.7.5

If xen-kmp is not installed, obtain it from the ISO file and install it.

If you add built-in drivers to the initrd or initramfs file by mistake, the ECS will not be affected.

Before installing the drivers, run the following command to check whether xen-kmp (driver package for Xen PV) is installed:

rpm -qa |grep xen-kmp

If information similar to the following is displayed, xen-kmp is installed:

xen-kmp-default-4.2.2_04_3.0.76_0.11-0.7.5

If xen-kmp is not installed, obtain it from the ISO package and install it first.

1. Run the following command to open the /etc/sysconfig/kernel file:

   vi /etc/sysconfig/kernel

2. Add Xen PV and VirtIO drivers after INITRD_MODULES= (the format varies depending on the OS).

   SIA10000xxxxx:~ # vi /etc/sysconfig/kernel 
   # (like drivers for scsi-controllers, for lvm or reiserfs)
   #
   INITRD_MODULES="ata_piix ata_generic xen_vnif xen_vbd xen_platform_pci virtio_blk virtio_scsi virtio_net virtio_pci virtio_ring virtio"

3. Run the dracut -f command to regenerate initrd.
   

   If the virtual file system is not the default initramfs or initrd, run dracut -f Name of the initramfs or initrd file actually used. The actual initramfs or initrd file name can be obtained from the menu.lst or grub.cfg file (/boot/grub/menu.lst, /boot/grub/grub.cfg, or /boot/grub2/grub.cfg).

   The following is an example initrd file of SUSE 11 SP4:

   default 0
   timeout 10
   gfxmenu (hd0,0)/boot/message
   title sles11sp4_001_[_VMX_]
   root (hd0,0)
   kernel /boot/linux.vmx vga=0x314 splash=silent console=ttyS0,115200n8 console=tty0 net.ifnames=0 NON_PERSISTENT_DEVICE_NAMES=1 showopts
   initrd /boot/initrd.vmx
   title Failsafe_sles11sp4_001_[_VMX_]
   root (hd0,0)
   kernel /boot/linux.vmx vga=0x314 splash=silent ide=nodma apm=off noresume edd=off powersaved=off nohz=off highres=off processsor.max+cstate=1 nomodeset x11failsafe console=ttyS0,115200n8 console=tty0 net.ifnames=0 NON_PERSISTENT_DEVICE_NAMES=1 showopts
   initrd /boot/initrd.vmx

   /boot/initrd.vmx is the initrd file actually used. If /boot is missing in the initrd file path, you need to add it when you run the dracut -f command. In this case, the command should be dracut -f /boot/initramfs-xxx.

4. Run the following commands to check whether Xen PVOPS and KVM VirtIO drivers have been installed:

   lsinitrd /boot/initrd-`uname -r` | grep xen

   lsinitrd /boot/initrd-`uname -r` | grep virtio

   SIA10000xxxxx:~ # lsinitrd /boot/initrd-`uname -r` | grep xen
   -rwxr--r-- 1 root root 42400 Jun 22 2012 lib/modules/2.6.32-279.el6.x86_64/kernel/drivers/block/xen-blkfront.ko
   -rwxr--r-- 1 root root 44200 Jun 22 2012 lib/modules/2.6.32-279.el6.x86_64/kernel/drivers/net/xen-netfront.ko
   
   SIA10000xxxxx:~ # lsinitrd /boot/initrd-`uname -r` | grep virtio
   -rwxr--r-- 1 root root 19248 Jun 22 2012 lib/modules/2.6.32-279.el6.x86_64/kernel/drivers/scsi/virtio_scsi.ko
   -rwxr--r-- 1 root root 23856 Jun 22 2012 lib/modules/2.6.32-279.el6.x86_64/kernel/drivers/block/virtio_blk.ko
   drwxr-xr-x 2 root root 0 Jul 12 14:53 lib/modules/2.6.32-279.el6.x86_64/kernel/drivers/virtio
   -rwxr--r-- 1 root root 15848 Jun 22 2012 lib/modules/2.6.32-279.el6.x86_64/kernel/drivers/virtio/virtio_ring.ko
   -rwxr--r-- 1 root root 20008 Jun 22 2012 lib/modules/2.6.32-279.el6.x86_64/kernel/drivers/virtio/virtio_pci.ko
   -rwxr--r-- 1 root root 12272 Jun 22 2012 lib/modules/2.6.32-279.el6.x86_64/kernel/drivers/virtio/virtio.ko
   -rwxr--r-- 1 root root 38208 Jun 22 2012 lib/modules/2.6.32-279.el6.x86_64/kernel/drivers/net/virtio_net.ko

5. Restart the ECS.
6. Modify the /boot/grub/menu.lst file to add xen_platform_pci.dev_unplug=all and change the root settings.

   Before the modification:

   ###Don't change this comment -YaST2 identifier: Original name: linux###
   title SUSE Linux Enterprise Server 11SP4 - 3.0.76-0.11 (default) 
   root (hd0,0) 
   kernel /boot/vmlinuz-3.0.76-0.11-default root=UUID=4eb40294-4c6f-4384-bbb6-b8795bbb1130 splash=silentcrashkernel=256M-:128M showopts vga=0x314
   initrd /boot/initrd-3.0.76-0.11-default

   After the modification:

   ###Don't change this comment -YaST2 identifier: Original name: linux###
   title SUSE Linux Enterprise Server 11SP4 - 3.0.76-0.11 (default) 
   root (hd0,0) 
   kernel /boot/vmlinuz-3.0.76-0.11-default root=UUID=4eb40294-4c6f-4384-bbb6-b8795bbb1130 splash=silentcrashkernel=256M-:128M showopts vga=0x314 xen_platform_pci.dev_unplug=all 
   initrd /boot/initrd-3.0.76-0.11-default

   

   • Ensure that the root partition is in UUID format.
   • xen_platform_pci.dev_unplug=all is used to shield QEMU devices.
   • For SUSE 11 SP1 64bit to SUSE 11 SP4 64bit, add xen_platform_pci.dev_unplug=all to the menu.lst file. For SUSE 12 or later, QEMU device shield is enabled by default, and you do not need to configure it.
7. Run the following commands to check whether Xen drivers exist in initrd:

   lsinitrd /boot/initrd-`uname -r` | grep xen

   lsinitrd /boot/initrd-`uname -r` | grep virtio

   SIA10000xxxxx:~ # lsinitrd /boot/initrd-`uname -r` | grep xen
   -rwxr--r-- 1 root root 42400 Jun 22 2012 lib/modules/2.6.32-279.el6.x86_64/kernel/drivers/block/xen-blkfront.ko
   -rwxr--r-- 1 root root 44200 Jun 22 2012 lib/modules/2.6.32-279.el6.x86_64/kernel/drivers/net/xen-netfront.ko
   
   SIA10000xxxxx:~ # lsinitrd /boot/initrd-`uname -r` | grep virtio
   -rwxr--r-- 1 root root 19248 Jun 22 2012 lib/modules/2.6.32-279.el6.x86_64/kernel/drivers/scsi/virtio_scsi.ko
   -rwxr--r-- 1 root root 23856 Jun 22 2012 lib/modules/2.6.32-279.el6.x86_64/kernel/drivers/block/virtio_blk.ko
   drwxr-xr-x 2 root root 0 Jul 12 14:53 lib/modules/2.6.32-279.el6.x86_64/kernel/drivers/virtio
   -rwxr--r-- 1 root root 15848 Jun 22 2012 lib/modules/2.6.32-279.el6.x86_64/kernel/drivers/virtio/virtio_ring.ko
   -rwxr--r-- 1 root root 20008 Jun 22 2012 lib/modules/2.6.32-279.el6.x86_64/kernel/drivers/virtio/virtio_pci.ko
   -rwxr--r-- 1 root root 12272 Jun 22 2012 lib/modules/2.6.32-279.el6.x86_64/kernel/drivers/virtio/virtio.ko
   -rwxr--r-- 1 root root 38208 Jun 22 2012 lib/modules/2.6.32-279.el6.x86_64/kernel/drivers/net/virtio_net.ko

   

   If you add built-in drivers to the initrd or initramfs file by mistake, the ECS will not be affected. The drivers cannot be found by running the lsinitrd command. You can run the following commands to check whether built-in drivers are in the kernel:

   cat /boot/config-`uname -r` | grep CONFIG_VIRTIO | grep y

   cat /boot/config-`uname -r` | grep CONFIG_XEN | grep y

1. Run the following command to open the /etc/dracut.conf file:

   vi /etc/dracut.conf

2. Press i to enter editing mode and add Xen PV and VirtIO drivers to add-drivers (the format varies depending on the OS).

   [root@CTU10000xxxxx ~]# vi /etc/dracut.conf 
   # additional kernel modules to the default
   add_drivers+="ata_piix ata_generic xen_vnif xen_vbd xen_platform_pci virtio_blk virtio_scsi virtio_net virtio_pci virtio_ring virtio"

3. Press Esc, enter :wq, and press Enter. The system saves the change and exits the /etc/dracut.conf file.
4. Run the following command to regenerate initrd:

   dracut -f /boot/initramfs-File name

   If the virtual file system is not the default initramfs, run the dracut -f Name of the initramfs or initrd file actually used command. The actual initramfs or initrd file name can be obtained from the grub.cfg file, which can be /boot/grub/grub.cfg, /boot/grub2/grub.cfg, or /boot/grub/grub.conf depending on the OS.

5. Check whether native Xen and KVM drivers have been installed. If the virtual file system is initramfs, run the following commands:

   lsinitrd /boot/initramfs-`uname -r`.img | grep xen

   lsinitrd /boot/initramfs-`uname -r`.img | grep virtio

   If the virtual file system is initrd, run the following commands:

   lsinitrd /boot/initrd-`uname -r` | grep xen

   lsinitrd /boot/initrd-`uname -r` | grep virtio