notes on system template auto-download, seeding (#580)

Related apache/cloudstack#11656

---------

Signed-off-by: Abhishek Kumar <abhishek.mrt22@gmail.com>

Author: shwstppr

source/adminguide/systemvm.rst

@@ -76,11 +76,20 @@ templates for hypervisor and architecture which are in use in the zone
 if not already present will be automatically registered and seeded on
 the secondary storage.
 
-ARM 64-bit template(s) will be downloaded from the official repository
-and the same workflow for the registration and seeding will be used. If
-the automatic download and seeding of ARM 64-bit template fails, the
-template can be manually registered in a multi-architecture zone or
-will need manual registration and seeding in a ARM 64-bit only zone.
+Template(s) will be downloaded from the configured repository
+and the same workflow for the registration and seeding will be used.
+Repository for downloading the templates can be configured using
+/etc/cloudstack/management/server.properties file by updating the
+``system.vm.templates.download.repository`` property. If no custom
+repository is configured, templates will be downloaded from the default
+official repository.
+
+If the automatic download and seeding of template fails, the
+template can be registered and seeded manually.
+UI/API can be used to register the template if the secondary storage VM is
+running in the zone. In case the secondary storage VM is not present then
+manual registration and seeding can be done using ``cloud-install-sys-tmplt``
+script.
 
 
 Changing the Default System VM Template

source/installguide/management-server/_database.rst

@@ -286,6 +286,20 @@ MySQL. See :ref:`install-database-on-separate-node`.
    done.”
    If the servlet container is Tomcat7 the argument --tomcat7 must be used.
 
+   .. note::
+      Since 4.23.0, the ``cloudstack-setup-management`` command can download
+      System VM templates on demand when they are not present.
+
+      Use the ``--systemvm-templates`` argument to specify which templates to
+      download. Valid values are ``all``, ``kvm-aarch64``, ``kvm-x86_64``,
+      ``xenserver``, and ``vmware``. A comma-separated  list combining any of
+      these identifiers can also be supplied (for example
+      ``kvm-x86_64,xenserver``). If not specified, ``kvm-x86_64`` template
+      will be downloaded by default.
+
+      For offline environments, provide a custom repository URL with the
+      ``--systemvm-templates-repository`` argument so the installer can fetch
+      templates from an internal mirror.
 
 .. _install-database-on-separate-node:
 
@@ -518,4 +532,18 @@ The following command creates the cloud user on the database.
       so ensure that the firewalld is disabled or ensure the correct firewalld rules
       are in place to allow traffic to ports 8080, 8250 and 9090 to the management server.
 
+   .. note::
+      Since 4.23.0, the ``cloudstack-setup-management`` command can download
+      System VM templates on demand when they are not present.
+
+      Use the ``--systemvm-templates`` argument to specify which templates to
+      download. Valid values are ``all``, ``kvm-aarch64``, ``kvm-x86_64``,
+      ``xenserver``, and ``vmware``. A comma-separated  list combining any of
+      these identifiers can also be supplied (for example
+      ``kvm-x86_64,xenserver``). If not specified, ``kvm-x86_64`` template
+      will be downloaded by default.
+
+      For offline environments, provide a custom repository URL with the
+      ``--systemvm-templates-repository`` argument so the installer can fetch
+      templates from an internal mirror.
 

source/quickinstallationguide/qig.rst

@@ -402,23 +402,46 @@ up the management server by issuing the following command:
 
    # cloudstack-setup-management
 
-
-System Template Setup
-~~~~~~~~~~~~~~~~~~~~~
-
-CloudStack uses a number of system VMs to provide functionality for accessing 
-the console of Instances, providing various networking services, and
-managing various aspects of storage. 
-
-We need to download the systemVM Template and deploy that to the secondary storage.
-We will use the local path (/export/secondary) since we are already on the NFS server itself,
-but otherwise you would need to mount your Secondary Storage to a temporary mount point, and use
-that mount point instead of the /export/secondary path.
-
-Execute the following script:
+   .. note::
+      Since 4.23.0, the ``cloudstack-setup-management`` command
+      can download SystemVM templates on demand when they are not present.
+
+      Use the ``--systemvm-templates`` argument to specify which templates to
+      download. Valid values are ``all``, ``kvm-aarch64``, ``kvm-x86_64``,
+      ``xenserver``, and ``vmware``. A comma-separated  list combining any of
+      these identifiers can also be supplied (for example
+      ``kvm-x86_64,xenserver``). If not specified, ``kvm-x86_64`` template
+      will be downloaded by default.
+
+      For offline environments, provide a custom repository URL with the
+      ``--systemvm-templates-repository`` argument so the installer can fetch
+      templates from an internal mirror.
+
+
+System VM Template Setup
+~~~~~~~~~~~~~~~~~~~~~~~~
+
+CloudStack relies on several System VMs (for example SSVM and CPVM) to
+provide console access, networking services and storage management. Manual
+installation of System VM templates is not required in recent CloudStack
+releases. Since 4.16.0, automatic seeding of System VM templates has been
+supported; the ``cloudstack-management`` package historically included bundled
+templates and the Management Server seeded them to secondary storage during
+startup or when a secondary store was added to a zone. Starting with 4.23.0,
+CloudStack supports on-demand downloading of System VM templates when they
+are not present locally or bundled with the package.
+
+Templates are typically obtained in two ways: during initial setup via
+``cloudstack-setup-management`` or automatically at Management
+Server startup and secondary store addition (the Management Server
+will attempt to download and seed any missing templates).
+
+When automated mechanisms are unsuitable, templates can be downloaded and
+deployed to secondary storage using the helper script. On the secondary
+storage host (or a temporary mount of the secondary store) run::
 
 .. parsed-literal::
-  
+
    /usr/share/cloudstack-common/scripts/storage/secondary/cloud-install-sys-tmplt \
    -m /export/secondary \
    -u |sysvm64-url-kvm| \