Virtualized Clustered Multiprocessing (vCMP) is a feature of the BIG-IP® system that allows you to run multiple instances of the BIG-IP software on a single hardware platform. vCMP™ allocates a specific share of the hardware resources to each BIG-IP instance, or vCMP guest. Each guest that you create behaves as a separate BIG-IP device, having its own CPU, memory, and disk space. Each guest also has its own configuration file, log files, and kernel version.
vCMP™ is built on F5 Networks' CMP technology. CMP allows cluster members (that is, slots within a chassis or Traffic Management Microkernel (TMM) instances on an appliance) to work together to form a coherent, distributed traffic-processing system to share traffic load. vCMP takes this one step further by allowing you to create and run virtualized BIG-IP modules, using a standards-based, purpose-built hypervisor.
A vCMP system includes these main components.
|vCMP host||The vCMP host is the system-wide hypervisor that allows you to create, view, and manage all guests on the system. A vCMP host allocates system resources to guests as needed|
|Guest||A guest is an object that you create on the vCMP system for the purpose of running one or more BIG-IP® modules. A guest consists of a TMOS instance, plus one or more BIG-IP modules. Each guest has its own share of hardware resources that the vCMP host allocates to it, effectively making each guest function like a separate BIG-IP device.|
|VM||A VM is the portion of a guest that resides on a slot. For example, a guest that spans four slots comprises four VMs.|
|BIG-IP cluster||A BIG-IP cluster is the set of available slots (cluster members) on the chassis. You manage a BIG-IP cluster using the Clusters screens of the BIG-IP Configuration utility.|
|Virtual cluster||A virtual cluster is similar to a normal cluster on a chassis, except that unlike a normal cluster, a separate virtual cluster exists for each guest on the system. A virtual cluster contains only the portions of the slots that pertain to an individual guest. For example, if a guest spans two slots, then the two slot portions for the guest represent a virtual cluster. There is a one-to-one correlation of a virtual cluster to a guest.|
|Virtual disk||A virtual disk is the portion of disk space on a slot that the system has allocated to a guest. For example, if a guest spans three slots, the system creates three virtual disks for that guest. Each virtual disk is implemented as an image file with an .img extension, such as guest_A.img|
|Cluster IP address||A cluster IP address is a management IP address that you assign to a cluster to access the system. On a vCMP system, there are multiple cluster IP addresses: one for the BIG-IP cluster (to access the vCMP host), and one for each virtual cluster (to access each guest).|
|vCMP daemon||This daemon, named vcmpd, performs most of the work to create and manage guests, as well as configure the virtual network.|
|Virtual management network||The virtual management network contains the components necessary to connect a guest to the management network of the vCMP host.|
You activate the BIG-IP system license when you initially run the Setup Utility.
F5 Networks has the following recommendations for managing a vCMP system.
|vCMP provisioning||When you provision the vCMP feature, the BIG-IP system allocates most, but not all, of the disk space to the vCMP application volume. The system reserves approximately 1GB of disk space for other uses. If you want the system to reserve more than 1GB of disk space, such as for installing another version of the BIG-IP system in the future, you should do this prior to provisioning the vCMP feature. Doing so after you have provisioned the vCMP feature can produce unwanted results. When increasing the reserve space on the disk, the recommended amount of space to reserve is 8GB.|
|Network setup||When initially setting up the BIG-IP® system, you should physically wire each slot's management interface to an external bridge. This ensures that all vCMP guests are accessible, given that a guest can be deployed on any slot in the chassis, and the primary member for a guest's virtual cluster can migrate. When you follow this recommendation, you do not need to re-configure the vCMP host or any external networks when the primary member of a virtual cluster changes.|
|Local traffic configuration||When you are logged in to the vCMP host, you should not configure local traffic features (virtual servers, pools, profiles, and so on). To configure local traffic features, you must be logged in to a guest using the guest's cluster IP address, and the BIG-IP LTM™ module must be provisioned.|
|VLAN configuration||You should configure VLANs on the vCMP host instead of on the guest, because the VLANs specified in the guest are not guaranteed to be configured on the vCMP host. Also, if two guests each have a VLAN group, verify that the VLAN group for each guest does not bridge the same two VLANs.|
|Licensing||Before upgrading a guest to a newer version of BIG-IP software later, you might need to coordinate with the vCMP host administrator to renew the license key.|
|Guest configuration||If you need to move a guest's configuration to another vCMP system (chassis), you should copy the guest configuration and then de-allocate all virtual resources (virtual disk, CPU cores, and so on) from the guest.|
|Virtual disk management||When a virtual disk becomes unattached from a guest, that virtual disk remains on the system. To prevent unattached virtual disks from consuming disk space over time, you should routinely delete any unwanted virtual disks from the system.|