4. Organization Catalogs : 4.1 Understanding Catalogs
4.1 Understanding Catalogs
The vSphere approach to implementing catalog-like functionality helps to understand the contents of a vCloud catalog and how the catalog is used. Although vSphere does not use the concept of a catalog, it achieves similar functionality with virtual machine templates and media files (ISO/FLP). The following steps outline how to build a fairly common Linux, Apache, MySQL, and PHP (LAMP) stack configuration in vSphere.
1. Gather the relevant media. In some cases the media are readily available for download in the form of ISO files from operating system vendors. Applications might be available only as binaries, in the form of tar, zip, or RPM files. You can copy binaries directly to a virtual machine with tools such as FTP or SCP or by bundling the binaries into an ISO file. These ISO files are then typically available on a dedicated, shared datastore.
2. Create virtual machine templates with a bare guest operating system installed on each template, and clone them to create instances of virtual machines to install applications. You can use a single template to create a web server, application server, and database server. Users can mix and match templates to satisfy use case requirements.
3. After deploying virtual machines from templates, you can customize each virtual machine for its specific purpose by installing Apache/PHP, Tomcat, and MySQL software binaries, either directly or by mounting a custom ISO image.
4. After the individual virtual machines are configured, an administrator can clone them to templates for future use.
vSphere cannot transform a vApp into a template. Any modifications to a vApp require that templates be converted back to virtual machines. Only the virtual machines can be modified.
The following sections discuss how vCloud Director implements the same functionality.