Cloud restart for vm failover and capacity management

Abstract

A method of restarting a virtual machine (VM) running in a cluster of hosts in a first data center, in a second data center, includes: transmitting an image of the VM to the second data center; in response to determining that a host in the cluster in which the VM was running has failed, determining whether or not there are sufficient resources in the cluster to run the VM in another host in the cluster; and upon determining that there are not sufficient resources in the cluster to run the VM in another host in the cluster, setting the VM to be inactive in the first data center, and communicating with a control plane in the second data center to set as active, and power on, a VM in the second data center using the image of the VM that has been transmitted to the second data center.

We claim: 
     
         1 . A method of restarting a virtual machine running in a cluster of hosts in a first data center, in a second data center, the method comprising:
 transmitting an image of the virtual machine to the second data center;   in response to determining that one of the hosts in the cluster in which the virtual machine was running has failed, determining whether or not there are sufficient resources in the cluster to run the virtual machine in another one of the hosts in the cluster; and   upon determining that there are not sufficient resources in the cluster to run the virtual machine in another one of the hosts in the cluster, setting the virtual machine to be inactive in the first data center, and communicating with a control plane in the second data center to set as active, and power on, a virtual machine in the second data center using the image of the virtual machine that has been transmitted to the second data center.   
     
     
         2 . The method of  claim 1 , wherein the cluster of hosts is not assigned a spare host in the first data center. 
     
     
         3 . The method of  claim 1 , wherein the first data center is an on-premises data center serving one tenant and the second data center is a cloud data center serving a plurality of tenants. 
     
     
         4 . The method of  claim 1 , further comprising:
 after setting the virtual machine to be inactive in the first data center, upon detecting that sufficient resources have been freed up in one of the hosts in the cluster of hosts to run the virtual machine therein, notifying the control plane in the second data center that the sufficient resources have been freed up.   
     
     
         5 . The method of  claim 4 , further comprising:
 updating the image of the virtual machine with data received from the second data center in response to said notifying; and   setting as active, and powering on, the virtual machine using the updated image of the virtual machine.   
     
     
         6 . The method of  claim 1 , further comprising:
 in response to determining that a performance of another virtual machine having higher priority than the virtual machine is below a minimum performance threshold, setting the virtual machine to be inactive in the first data center, and communicating with the control plane in the second data center to set as active, and power on, the virtual machine in the second data center using the image of the virtual machine that has been transmitted to the second data center.   
     
     
         7 . The method of  claim 1 , wherein a portion of the image of the virtual machine is transmitted to the second data center prior to determining that the host in which the virtual machine was running has failed. 
     
     
         8 . A computer system comprising:
 a memory configured to store executable code for restarting a virtual machine running in a cluster of hosts in a first data center, to a second data center, and a processor configured to execute the code to:   transmit an image of the virtual machine to the second data center;   in response to determining that one of the hosts in the cluster in which the virtual machine was running has failed, determine whether or not there are sufficient resources in the cluster to run the virtual machine in another one of the hosts in the cluster; and   upon determining that there are not sufficient resources in the cluster to run the virtual machine in another one of the hosts in the cluster, set the virtual machine to be inactive in the first data center, and communicate with a control plane in the second data center to set as active, and power on, a virtual machine in the second data center using the image of the virtual machine that has been transmitted to the second data center.   
     
     
         9 . The computer system of  claim 8 , wherein the cluster of hosts is not assigned a spare host in the first data center. 
     
     
         10 . The computer system of  claim 8 , wherein the first data center is an on-premises data center serving one tenant and the second data center is a cloud data center serving a plurality of tenants. 
     
     
         11 . The computer system of  claim 8 , wherein the processor is configured to execute the code to:
 after setting the virtual machine to be inactive in the first data center, upon detecting that sufficient resources have been freed up in one of the hosts in the cluster of hosts to run the virtual machine therein, notify the control plane in the second data center that the sufficient resources have been freed up.   
     
     
         12 . The computer system of  claim 11 , wherein the processor is configured to execute the code to:
 update the image of the virtual machine with data received from the second data center in response to said notifying; and   set as active, and power on, the virtual machine using the updated image of the virtual machine.   
     
     
         13 . The computer system of  claim 8 , wherein the processor is configured to execute the code to:
 in response to determining that a performance of another virtual machine having higher priority than the virtual machine is below a minimum performance threshold, set the virtual machine to be inactive in the first data center, and communicate with the control plane in the second data center to set as active, and power on, the virtual machine in the second data center using the image of the virtual machine that has been transmitted to the second data center.   
     
     
         14 . The computer system of  claim 8 , wherein a portion of the image of the virtual machine is transmitted to the second data center prior to determining that the host in which the virtual machine was running has failed. 
     
     
         15 . A non-transitory computer-readable medium storing code for causing, when executed by a processor, restarting of a virtual machine running in a cluster of hosts in a first data center, to a second data center, the processor when executing the code performing the steps of:
 transmitting an image of the virtual machine to the second data center;   in response to determining that one of the hosts in the cluster in which the virtual machine was running has failed, determining whether or not there are sufficient resources in the cluster to run the virtual machine in another one of the hosts in the cluster; and   upon determining that there are not sufficient resources in the cluster to run the virtual machine in another one of the hosts in the cluster, setting the virtual machine to be inactive in the first data center, and communicating with a control plane in the second data center to set as active, and power on, a virtual machine in the second data center using the image of the virtual machine that has been transmitted to the second data center.   
     
     
         16 . The non-transitory computer readable medium of  claim 15 , wherein the cluster of hosts is not assigned a spare host in the first data center. 
     
     
         17 . The non-transitory computer readable medium of  claim 15 , wherein the steps further comprise:
 after setting the virtual machine to be inactive in the first data center, upon detecting that sufficient resources have been freed up in one of the hosts in the cluster of hosts to run the virtual machine therein, notifying the control plane in the second data center that the sufficient resources have been freed up.   
     
     
         18 . The non-transitory computer readable medium of  claim 17 , wherein the steps further comprise:
 updating the image of the virtual machine with data received from the second data center in response to said notifying; and   setting as active, and powering on, the virtual machine using the updated image of the virtual machine.   
     
     
         19 . The non-transitory computer readable medium of  claim 15 , wherein the steps further comprise:
 in response to determining that a performance of another virtual machine having higher priority than the virtual machine is below a minimum performance threshold, setting the virtual machine to be inactive in the first data center, and communicating with the control plane in the second data center to set as active, and power on, the virtual machine in the second data center using the image of the virtual machine that has been transmitted to the second data center.   
     
     
         20 . The non-transitory computer readable medium of  claim 15 , wherein a portion of the image of the virtual machine is transmitted to the second data center prior to determining that the host in which the virtual machine was running has failed.