1. Introduction to Explicit Dedication
of Resources
Apache CloudStack
Saksham Srivastava
CloudStack Developer

2. InfraStructure Layout
Zone
Pod
Cluster
Host

3. Explicitly Dedicating resources
• Allowing CloudStack infrastructure to be
dedicated to specific users/accounts.
• What can be dedicated ?
Zone / Pod / Cluster / Host

4. Why dedicate
• CloudStack is multi tenant architecture
• A tenant wants reserved hardware usable only
by him and his users.
• Premium user wants to have his vms staying on
hosts dedicated to him (pro-affinity).
• Allows dedicated compute available to the user.

5. Dedicated Resources
• Only the account/domain to which the resource has
been dedicated can use the dedicated resource.
• If a cluster is dedicated to an account, all the hosts in
it are also dedicated to the same account
• If a pod is dedicated, all clusters in it are also
dedicated
• Similarly if a zone is dedicated, all pods are also
dedicated

6. APIs
Dedicating
Resources
dedicateZone
dedicatePod
dedicateCluster
dedicateHost
Release dedication of
Resources
releaseDedicatedZone
releaseDedicatedPod
releaseDedicatedCluster
releaseDedicatedHost
Listing Dedicated
Resources
listDedicatedZones
listDedicatedPods
listDedicatedClusters
listDedicatedHost

7. Affinity Group
• When a resource is dedicated to an
account/domain CloudStack internally creates an
affinity group of type ExplicitDedication
• CloudStack internally refers it as Processor and
uses it decide the vm deployment location.
• If the account uses this affinity group while
deploying the vm, the vm will be placed on the
resource dedicated to it
• If this affinity group is not chosen, the vm is
deployed on shared host (non-dedicated host)

8. A simple scenario
•
•
•
•
•
2 accounts Blue and Red
3 Hosts
Host 1 dedicated to account Blue
Host 3 dedicated to account Red
Host 2 is undedicated (shared)

9. Host Dedicated to
account Blue
Shared Host
Host Dedicated to
account Red
A
A
A
VM deployed from account Blue using affinity group
A
VM deployed from account Red using affinity group
VM deployed from account Blue without affinity group
VM deployed from account Red without affinity group

10. Note
• Only Root admin can dedicate/release
• System VMs and Virtual Router do not adhere
to explicit dedication as they are owned by
the system account and can be deployed on
any host.
• Admin can live migrate a VM deployed on
dedicated resource to a resource not owned
by the account, but suitable alerts are
generated by CloudStack

11. Resources
• This is an introduction to Explicit dedication.
Please refer to the Functional Specification for
more detailed explanation :
https://cwiki.apache.org/confluence/display/CLO
UDSTACK/Dedicated+Resources++Private+zone%2C+pod%2C+cluster%2C+host+Fu
nctional+Spec

12. Thanks,
Saksham Srivastava
@sakkuboy