CentOS Linux Templates

CentOS Linux 7.6 x64

• Issues: There is no VNC console for Xen guests as Red Hat dropped Xen DomU support on 7.x releases.
• Limitation: Includes only new grub2 installed, so isn't supported by old OnApp versions < 5.5.

CentOS Linux 7.6 x64 (with kernel-plus)

• Issues: No.
• Limitation: Uses kernel-plus to solve VNC console issue under Xen. Includes only new grub2 installed, so isn't supported by old OnApp versions < 5.5.

CentOS Linux 7.6 x64 (with legacy grub)

• Issues: No.
• Limitation: Includes a legacy grub installed version 0.97-99.el6.

CentOS Linux 7.7 x64 (with legacy grub)

• Issues: There is no VNC console for Xen guests as Red Hat dropped Xen DomU support on 7.x releases.
• Limitation: Includes a legacy grub installed version 0.97-99.el6.

CentOS Linux 7.8 x64

• Issues: There is no VNC console for Xen guests as Red Hat dropped Xen DomU support on 7.x releases.
• Limitations: none.

CentOS 7.9 x64

• Issues: There is no VNC console for Xen guests as Red Hat dropped Xen DomU support on 7.x releases.
• Limitations: none.

CentOS 7.9 plus x64

• Issues: no.
• Limitations: Uses kernel-plus to solve VNC console issue under Xen.

CentOS 7.9 TOD x64

• Issues: There is no VNC console for Xen guests as Red Hat dropped Xen DomU support on 7.x releases.

CentOS 7.9 TOD v0.0.9 x64

• Issues: There is no VNC console for Xen guests as Red Hat dropped Xen DomU support on 7.x releases.

CentOS 7.9 TOD v0.0.10 x64

• Issues: There is no VNC console for Xen guests as Red Hat dropped Xen DomU support on 7.x releases.

CentOS 7.9 TOD v0.1.0 x64

• Issues: There is no VNC console for Xen guests as Red Hat dropped Xen DomU support on 7.x releases.

CentOS 7.9 TOD v0.1.x x64

• Issues: There is no VNC console for Xen guests as Red Hat dropped Xen DomU support on 7.x releases.

CentOS 7.9 TOD v0.2.0 x64

• Issues: There is no VNC console for Xen guests as Red Hat dropped Xen DomU support on 7.x releases.

CentOS 7.9 TOD v0.2.1 x64

• Issues: There is no VNC console for Xen guests as Red Hat dropped Xen DomU support on 7.x releases.

CentOS Linux 8.0 x64

• Issues: After operating system upgrade (with 'yum update') and before reboot, please check and modify GRUB_ENABLE_BLSCFG option's value (set it into 'false',) in GRUB2 boot loader's default configuration file /etc/default/grub. Then generate new GRUB2 boot loader's main config with:

  # grub2-mkconfig -o /boot/grub2/grub.cfg

  Reboot the system (if required).

• Limitation: The template isn't compatible with Xen. Red Hat Enterprise Linux release 8.x and its clones (like CentOS Linux) can't run as Xen PV DomU (the kind of model OnApp runs Linux guests) anymore. Xen PV guest support has been disabled for all 8.x releases.

• Technical details:

  # cat /etc/redhat-release 
  CentOS Linux release 8.0.1905 (Core)
  # uname -r
  4.18.0-80.7.1.el8_0.x86_64
  # grep -i CONFIG_XEN_PV /boot/config-`uname -r`
  # CONFIG_XEN_PV is not set

  The reason is CONFIG_XEN_PV Linux kernel configuration item (was introduced in Linux kernel versions >= *4.12*) unset on the kernel;
  prompt: Xen PV guest support
  type: bool
  depends on: CONFIG_XEN
  defined in arch/x86/xen/Kconfig
  found in Linux kernels: 4.12–4.20, 5.0–5.2, 5.3-rc+HEAD
  Help text: Support running as a Xen PV guest.

CentOS Linux 8.0 kernel_ml x64

• Issues: After operating system upgrade (with 'yum update') and before reboot, please check and modify GRUB_ENABLE_BLSCFG option's value (set it into 'false',) in GRUB2 boot loader's default configuration file /etc/default/grub. Then generate new GRUB2 boot loader's main config with:

  # grub2-mkconfig -o /boot/grub2/grub.cfg

  Reboot the system (if required).

• Limitation: Using the kernel-ml may expose your system to security, performance and/or data corruption issues. Since timely updates may not be available from the ELRepo Project, the end user has the ultimate responsibility for deciding whether to continue using the kernel-ml packages in regular service. These packages are not signed for SecureBoot.

CentOS Linux Release 8.1.1911

• Issues: After operating system upgrade (with 'yum update') and before reboot, please check and modify GRUB_ENABLE_BLSCFG option's value (set it into 'false',) in GRUB2 boot loader's default configuration file /etc/default/grub. Then generate new GRUB2 boot loader's main config with:

  # grub2-mkconfig -o /boot/grub2/grub.cfg

  Reboot the system (if required).

• Limitation:
  The template isn't compatible with Xen
  Red Hat Enterprise Linux release 8.x and its clones (like CentOS Linux) can't run as Xen PV DomU (the kind of model OnApp runs Linux guests) anymore. Xen PV guest support has been disabled for all 8.x releases.

• Technical details:

  # cat /etc/redhat-release 
  CentOS Linux release 8.1.1911
  
  # uname -r
  4.18.0-147.3.1.el8_1.x86_64
  # grep -i CONFIG_XEN_PV /boot/config-`uname -r`
  # CONFIG_XEN_PV is not set

  The reason is CONFIG_XEN_PV Linux kernel configuration item (was introduced in linux kernel versions >= *4.12*) unset on the kernel;

prompt: Xen PV guest support
type: bool
depends on: CONFIG_XEN
defined in arch/x86/xen/Kconfig
found in Linux kernels: 4.12–4.20, 5.0–5.2, 5.3-rc+HEAD
Help text: Support running as a Xen PV guest.

CentOS Linux Release 8.2.2004 (Core)

• Issues: After operating system upgrade (with 'yum update') and before reboot, please check and modify GRUB_ENABLE_BLSCFG option's value (set it into 'false',) in GRUB2 boot loader's default configuration file /etc/default/grub. Then generate new GRUB2 boot loader's main config with:

  # grub2-mkconfig -o /boot/grub2/grub.cfg

  Reboot the system (if required).

• Limitation: The template isn't compatible with Xen.

CentOS Linux Release 8.3.2011

• Issues: After operating system upgrade (with 'yum update') and before reboot, please check and modify GRUB_ENABLE_BLSCFG option's value (set it into 'false',) in GRUB2 boot loader's default configuration file /etc/default/grub. Then generate new GRUB2 boot loader's main config with:

  # grub2-mkconfig -o /boot/grub2/grub.cfg

  Reboot the system (if required).

• Limitation: The template isn't compatible with Xen.

CentOS Linux Release 8.3.2011 (kernel_ml)

• Issues: After an operating system upgrade (with 'yum update') and before reboot, please check and modify GRUB_ENABLE_BLSCFG option's value (set it into 'false',) in GRUB2 boot loader's default configuration file /etc/default/grub. Then generate new GRUB2 boot loader's main config with:

  # grub2-mkconfig -o /boot/grub2/grub.cfg

• Limitation: Usage of the kernel-ml may expose your system to security, performance, and/or data corruption issues. Since timely updates may not be available from the ELRepo Project, the end user has the ultimate responsibility for deciding whether to continue using the kernel-ml packages in regular service. These packages are not signed for SecureBoot. Reboot the system (if required).

CentOS Linux Release 8.4.2105

• Issues: After operating system upgrade (with 'yum update') and before reboot, please check and modify GRUB_ENABLE_BLSCFG option's value (set it into 'false',) in GRUB2 boot loader's default configuration file /etc/default/grub. Then generate new GRUB2 boot loader's main config with:

  # grub2-mkconfig -o /boot/grub2/grub.cfg

  Reboot the system (if required).

• Limitation: The template isn't compatible with Xen.

CentOS Linux Release 8.4.2105 (kernel_ml)

• Issues: After operating system upgrade (with 'yum update') and before reboot, please check and modify GRUB_ENABLE_BLSCFG option's value (set it into 'false',) in GRUB2 boot loader's default configuration file /etc/default/grub. Then generate new GRUB2 boot loader's main config with:

  # grub2-mkconfig -o /boot/grub2/grub.cfg

  Reboot the system (if required).

• Limitation: Using the kernel-ml may expose your system to security, performance and/or data corruption issues. Since timely updates may not be available from the ELRepo Project, the end user has the ultimate responsibility for deciding whether to continue using the kernel-ml packages in regular service. These packages are not signed for SecureBoot.

CentOS Linux Release 8.5.2111

• Issues: After operating system upgrade (with 'yum update') and before reboot, please check and modify GRUB_ENABLE_BLSCFG option's value (set it into 'false',) in GRUB2 boot loader's default configuration file /etc/default/grub. Then generate new GRUB2 boot loader's main config with:

  # grub2-mkconfig -o /boot/grub2/grub.cfg

   Reboot the system (if required).

• Limitation: The template isn't compatible with Xen.

CentOS Linux Release 8.5.2111 (kernel_ml)

• Issues: After operating system upgrade (with 'yum update') and before reboot, please check and modify GRUB_ENABLE_BLSCFG option's value (set it into 'false',) in GRUB2 boot loader's default configuration file /etc/default/grub. Then generate new GRUB2 boot loader's main config with:

  # grub2-mkconfig -o /boot/grub2/grub.cfg

  Reboot the system (if required).

• Limitation: Using the kernel-ml may expose your system to security, performance and/or data corruption issues. Since timely updates may not be available from the ELRepo Project, the end user has the ultimate responsibility for deciding whether to continue using the kernel-ml packages in regular service. These packages are not signed for SecureBoot.

CentOS Stream Release 8

• Issues: After operating system upgrade (with 'yum update') and before reboot, please check and modify GRUB_ENABLE_BLSCFG option's value (set it into 'false',) in GRUB2 boot loader's default configuration file /etc/default/grub. Then generate new GRUB2 boot loader's main config with:

  # grub2-mkconfig -o /boot/grub2/grub.cfg

  Reboot the system (if required).

• Limitation: The template isn't compatible with Xen.

CentOS Stream Release 9

• Issues: network-scripts networking management has been deprecated in EL9. NetworkManager is now used. It isn't supported by OnApp.
  Because of that:
  - Assigning multiple IP addresses won't work;
  - Changing Primary IP Address with "Rebuild Network" (via OnApp UI) will require manual actions in VM's main console:
  

  # /etc/rc.d/init.d/el9NM2onapp start
  # nmcli dev reapply eth0

  
  

• Limitation:
  - The template isn't compatible with Xen;
  - The VM based on the template should be configured with correct CPU model. 
  The reason is that glibc-2.34-20 includes a fix to more reliably detect CPU compatibility. See the bug at https://bugzilla.redhat.com/show_bug.cgi?id=2040657. Such detection generates the following inside guest:
  "Fatal glibc error: CPU does not support x86-64-v2".

To configure the correct CPU model, refer to Configure CPU Model.