Mirror vote synchronization

Patent metadata

Field	Value
Publication number	US-10216450-B2
Application number	US-201615165006-A
Country	US
Kind code	B2
Filing date	May 26, 2016
Priority date	Mar 20, 2014
Publication date	Feb 26, 2019
Grant date	Feb 26, 2019

Abstract

One or more techniques and/or systems are provided for mirror vote synchronization. For example, a first storage device is located at a first storage site, and a second storage device is located at a second storage site. The second storage device is configured according to a data mirroring configuration where data from the first storage device is mirrored to the second storage device. Mirror vote metadata is generated based upon an up-to-date state of the data mirroring configuration. The mirror vote metadata indicates whether the first storage device and/or the second storage device are up-to-date or not. The mirror vote metadata may be replicated between the first storage site and the second storage site. If the first storage site fails, then the second storage site may provide switchover operation using the second storage device based upon the mirror vote metadata.

First claim

What is claimed is:

1. A method, comprising:
storing a local mirror vote received from a first site as a replicated mirror vote within a replication database accessible to a second site, wherein the local mirror vote specifies up-to-date and out-of-date status information for a first storage device at the first site and a second storage device at the second site; and
controlling operation of the second storage device to initialize the second storage device as a switchover storage aggregate for use by the second site, based upon the first site experiencing a disaster, by:
modifying operation of the second storage device to initialize the switchover storage aggregate in an offline state based upon a determination that the replication database is inaccessible for retrieving the replicated mirror vote for determining whether the second storage device is up-to-date; and
specifying that the switchover storage aggregate is in the offline state because the replicated mirror vote was unavailable.

2. The method of claim 1 , comprising:
determining whether to modify the operation of the second storage device to transition the switchover storage aggregate into an online state based upon whether the replicated mirror vote indicates that the second storage device is up-to-date, wherein the replicated mirror vote is retrieved from the replication database based upon the replication database becoming accessible.

3. The method of claim 2 , comprising:
modifying the operation of the second storage device to transition the switchover storage aggregate into the online state based upon the replicated mirror vote specifying that the the second storage device is up-to-date and the first storage device is out-of-date.

4. The method of claim 2 , comprising:
retaining the switchover storage aggregate in the offline state based upon the replicated mirror vote specifying that the first storage device is up-to-date and the second storage device is out-of-date.

5. The method of claim 1 , comprising:
performing a synchronization between the second storage device and the first storage device based upon the first site being restored.

6. The method of claim 1 , comprising:
modifying the operation of the second storage device to transition the switchover storage aggregate into an online state based upon the replicated mirror vote indicating that the second storage device is up-to-date and facilitating data access to the switchover storage aggregate utilizing the second storage device, wherein the replicated mirror vote is retrieved from the replication database based upon the replication database becoming accessible.

7. The method of claim 6 , comprising:
generating a switchover mirror vote based upon the data access, the switchover mirror vote indicating that the first storage device is out-of-date and that the second storage device is up-to-date based upon the data access to the second storage device modifying the second storage device.

8. The method of claim 7 , comprising:
replicating the switchover mirror vote from the second site to the first site as a restored mirror vote for use by the first site to determine which storage device of the first storage device and the second storage device to use for providing client devices with access to data and assigning ownership of the second storage device to the first site based upon the first site being restored.

9. The method of claim 7 , comprising:
storing the switchover mirror vote within a root storage location associated with the first site based upon the first site being restored.

10. The method of claim 1 , comprising:
storing the replicated mirror vote within a root storage location associated with the second site.

11. A computing device comprising:
a memory having stored thereon instructions for performing a method; and
a processor coupled to the memory, the processor configured to execute the instructions to cause the processor to:
store a local mirror vote received from a first site as a replicated mirror vote within a replication database accessible to a second site, wherein the local mirror vote specifies up-to-date and out-of-date status information for a first storage device at the first site and a second storage device at the second site; and
control operation of the second storage device to initialize the second storage device as a switchover storage aggregate for use by the second site, based upon the first site experiencing a disaster, by:
modifying operation of the second storage device to initialize the switchover storage aggregate in an offline state based upon a determination that the replication database is inaccessible for retrieving the replicated mirror vote for determining whether the second storage device is up-to-date; and
specifying that the switchover storage aggregate is in the offline state because the replicated mirror vote was unavailable.

12. The computing device of claim 11 , wherein the instructions cause the processor to:
modify the operation of the second storage device to transition the switchover storage aggregate into an online state based upon replicated mirror voting indicating that the second storage device is up-to-date and facilitating data access to the switchover storage aggregate utilizing the second storage device, wherein the replicated mirror vote is retrieved from the replication database based upon the replication database becoming accessible.

13. The computing device of claim 12 , wherein the instructions cause the processor to:
generating a switchover mirror vote based upon the data access, the switchover mirror vote indicating that the first storage device is out-of-date and that the second storage device is up-to-date based upon the data access to the second storage device modifying the second storage device.

14. The computing device of claim 13 , wherein the instructions cause the processor to:
performing a synchronization between the second storage device and the first storage device based upon the switchover mirror vote based upon the first site being restored.

15. The computing device of claim 11 , wherein the instructions cause the processor to:
determining whether to place the switchover storage aggregate into an online state based upon the replicated mirror vote, wherein the replicated mirror vote is retrieved from the replication database based upon the replication database coming online.

16. A non-transitory computer readable medium having stored thereon instructions which when executed by a machine, causes the machine to:
store a local mirror vote received from a first site as a replicated mirror vote within a replication database accessible to a second site, wherein the local mirror vote specifies up-to-date and out-of-date status information for a first storage device at the first site and a second storage device at the second site; and
control operation of the second storage device to initialize the second storage device as a switchover storage aggregate for use by the second site, based upon the first site experiencing a disaster, by:
modifying operation of the second storage device to initialize the switchover storage aggregate in an offline state based upon a determination that the replication database is inaccessible for retrieving the replicated mirror vote for determining whether the second storage device is up-to-date; and
specifying that the switchover storage aggregate is in the offline state because the replicated mirror vote was unavailable.

17. The non-transitory computer readable medium of claim 16 , wherein the instructions cause the m

Assignees

• Netapp Inc

Inventors

• Long Brandon Taylor
• Riedle Linda Ann
• Kulkarni Manali
• Nirmale Sandeep T
• Krishnamurthy Vikram Harakere

Classifications

• G06F11/2094

  Redundant storage or storage space (G06F11/2056 takes precedence) · CPC title

• H04L67/1095

  Replication or mirroring of data, e.g. scheduling or transport for data synchronisation between network nodes · CPC title

• G06F11/2082

  Data synchronisation · CPC title

• G06F3/067

  Distributed or networked storage systems, e.g. storage area networks [SAN], network attached storage [NAS] · CPC title

• H04L67/1097

  for distributed storage of data in networks, e.g. transport arrangements for network file system [NFS], storage area networks [SAN] or network attached storage [NAS] · CPC title