High availability for virtual network functions

1. A method comprising:

with a Virtual Network Function (VNF) manager, managing a VNF that includes a plurality of VNF components running on a plurality of virtual machines, the virtual machines running on a plurality of physical computing machines;

determining a first number that is equal to a number of virtual machines capable of providing for a current demand for VNF components;

determining a highest number of virtual machines being provided by a single one of the plurality of physical computing machines for the VNF and setting a second number to be equal to the highest number of virtual machines being provided by a single one of the plurality of physical computing machines; and

with the VNF manager, causing a Network Function Virtualization Infrastructure (NFVI) to have a total number of virtual machines provisioned, the total number being equal to the first number plus the second number.

2. The method of claim 1 , further comprising, detecting a change in the highest number of virtual machines being provided by the single one of the set of physical computing machines.

3. The method of claim 2 , further comprising, in response to determining that the change is a decrease, decommissioning at least one of the plurality of virtual machines.

4. The method of claim 2 , further comprising, in response to determining that the change is an increase, causing an additional virtual machine to be provisioned.

5. The method of claim 1 , further comprising, in response to detecting a change in the number of virtual machines capable of providing for the current demand for VNF components, adjusting the total number of virtual machines.

6. The method of claim 1 , further comprising, adjusting the total number based on current utilization of a network associated with the VNF.

7. The method of claim 1 , further comprising, adjusting the total number based on utilization of processors of the plurality of physical computing machines.

8. The method of claim 1 , further comprising, adjusting the total number based on a number of subscribers currently using a telecommunication service associated with the VNF.

9. The method of claim 1 , wherein the total number of virtual machines uses an active/active model.

10. The method of claim 1 , wherein the second number is subject to a set of constraints.

11. A system comprising:

a processor; and

a memory comprising machine readable instructions that when executed by the processor, cause the system to:

determine a first number that is equal to a number of virtual machines, each virtual machine associated with a Virtual Network Function (VNF) component, that is capable of meeting current demand for the VNF;

determine a highest number of virtual machines being provided by a single one of a plurality of physical computing machines for the VNF and setting a second number that is equal to the largest number of VNF components currently supported by a single one of the plurality of physical computing machines; and

cause a total number of virtual machines to be provisioned, the total number being equal to a sum of the first number and the second number.

12. The system of claim 11 , wherein to cause the total number of virtual machines to be provisioned, the system is further to add an additional virtual machine if the total number of virtual machines is greater than a current number of virtual machines.

13. The system of claim 11 , wherein to cause the total number of virtual machines to be provisioned, the system is further to decommission at least one of the virtual machines if the total number of virtual machines is less than a current number of virtual machines.

14. The system of claim 11 , wherein each of the total number of virtual machines is active.

15. The system of claim 11 , wherein to cause the total of virtual machines to be provisioned, the system is to send an instruction to a Network Function Virtualization Infrastructure (NFVI) manager, the instruction being to provision an additional virtual machine or decommission at least one virtual machine.

16. The system of claim 11 , wherein the system is further to adjust the total number based on at least one of: current utilization of a network associated with the VNF and utilization of processors of the plurality of physical computing machines that support the virtual machines.

17. The system of claim 11 , when the system is further to adjust the total number based on a number of subscribers currently using a telecommunication service associated with the VNF.