Distributed recovery of server information

Patent metadata

Field	Value
Publication number	US-11599427-B2
Application number	US-201817057122-A
Country	US
Kind code	B2
Filing date	Aug 2, 2018
Priority date	Aug 2, 2018
Publication date	Mar 7, 2023
Grant date	Mar 7, 2023

Abstract

In some examples, a first computing device may receive, from a server, an indication that the server has recovered data. For instance, the first computing device may store metadata including a mapping for one or more file systems accessed by one or more client devices. Furthermore, a second computing device may store a copy of the mapping stored on the first computing device. The first computing device may receive, from the server, a mapping of the one or more file systems determined by the server based on the recovered data. The first computing device may compare the mapping from the server with the mapping of the one or more file systems on the first computing device, and may send, to the server, information about changes determined between the two mappings to enable the server to update the mapping on the server based on the changes.

First claim

The invention claimed is:

1. A system comprising:
a first computing device including one or more processors configured by executable instructions to perform operations comprising:
receiving, by the first computing device, from a server, an indication that the server has recovered backed up metadata to a server metadata database maintained by the server, wherein the first computing device stores, in a first metadata database, metadata including a file system mapping for one or more file systems accessed by one or more client devices via the first computing device, wherein a second computing device is configured to store, to a second metadata database, a copy of the file system mapping stored by the first computing device;
based on the server having performed recovery of the backed up metadata to the server metadata database, receiving, by the first computing device, from the server, a recovered file system mapping of the one or more file systems determined by the server from the backed up metadata recovered by the server;
in response to receiving from the server the recovered file system mapping determined from the recovered backed up metadata, comparing, by the first computing device, the recovered file system mapping received from the server with the file system mapping of the one or more file systems stored by the first computing device in the first metadata database, wherein the comparing by the first computing device comprises comparing each share path and file system identifier in the recovered file system mapping from the server with each share path and file system identifier in the file system mapping on the first computing device; and
sending, by the first computing device, to the server, information about changes determined between the file system mapping stored by the first computing device and the recovered file system mapping received from the server to enable the server to update the recovered file system mapping in the server metadata database based on the information about the changes determined between the file system mapping stored by the first computing device and the recovered file system mapping received from the server.

2. The system as recited in claim 1 , the operations further comprising sending, to the server, one or more files stored locally on the first computing device with an indication to one of: update an existing file or store as a new file.

3. The system as recited in claim 1 , further comprising:
receiving, by the first computing device, from the server, a mapping identifier (ID) indicating a mirror set including the first computing device and the second computing device;
comparing the mapping ID received from the server with a mapping ID on the first computing device; and
based on determining that the mapping ID received from the server matches the mapping ID on the first computing device, requesting, by the first computing device, the recovered file system mapping of the one or more file systems determined by the server from the backed up metadata recovered by the server to the server metadata database.

4. The system as recited in claim 1 , wherein:
based at least on the server recovering the backed up metadata to the server metadata database, the second computing device receives, from the server, an indication that a role of the second computing device is to store, in the second metadata database, a copy of the file system mapping stored by the first computing device in the first metadata database; and
based on determining that the server has completed recovering data, the second computing device receives, from the server, updated file system mapping information determined based at least in part on the information about the changes sent to the server by the first computing device.

5. The system as recited in claim 1 , wherein:
based at least on the server recovering the backed up metadata to the server metadata database, the second computing device receives, from the server, an indication that a role of the second computing device has changed to a role of the first computing device;
receiving, by the second computing device, from the server, the recovered file system mapping of the one or more file systems; and
comparing, by the second computing device, the recovered file system mapping from the server with the file system mapping of the one or more file systems on the second computing device.

6. The system as recited in claim 1 , the operations further comprising, prior to receiving the indication that the server has recovered data, receiving, by the first computing device, from the server, an instruction to cause the first server to at least one of:
replicate the one or more file systems to the second computing device; or
replicate updates to the one or more file systems to the second computing device.

7. The system as recited in claim 6 , wherein the first computing device and the second computing device are assigned a same mapping identifier based on the second computing device being configured to store, in the second metadata database, the copy of the file system mapping stored by the first computing device in the first metadata database, the mapping identifier corresponding to the file system mapping stored by the first computing device.

8. The system as recited in claim 1 , the operations further comprising:
receiving, by the first service computing device, from the server, a transaction identifier (ID) that indicates a last transaction processed according to the recovered file system mapping from the server;
comparing the transaction ID received from the server with a transaction ID on the first computing device; and
based on the transaction ID on the first computing device being greater than the transaction ID from the server, comparing, by the first computing device, the recovered file system mapping from the server with the file system mapping of the one or more file systems on the first computing device.

9. The system as recited in claim 1 , further comprising sending, to the server, a local share on the first computing device having a share file system identifier that is the same as a server share file system identifier and a different share path from a server share path.

10. The system as recited in claim 1 , further comprising sending, to the server, a local share on the first computing device having a share path that is the same as a server share path and a different share file system identifier from a server share file system identifier.

11. The system as recited in claim 1 , wherein the first computing device is configured to communicate with at least one of the client computing devices for sending client data to the at least one client computing device and receiving client data from the at least one client computing device, wherein the client data is stored based on at least one of the file systems.

12. The system as recited in claim 1 , the operations further comprising:
prior to sending to the server the information about the changes determined between the file system mapping stored by the first computing device and the recovered file system mapping received from the server, receiving, by the first computing device, from the server, a request to synchronize at least one of a file read or a file write; and
disregarding, by the first computing device, the request based on determining that recovery of the server metadata database by the server is incomplete.

13. A method comprising:
receiving, by one or more processors of a first computing device, from a server, an indication that the server has recovered backed up metadata to a server metadata database maintained by the server, wherein

Assignees

• Hitachi Vantara Llc

Inventors

• Clark Ngale
• Miller Christopher
• Yaninas Scott
• Gross Jeffrey

Classifications

• G06F2201/84

  Using snapshots, i.e. a logical point-in-time copy of the data · CPC title

• G06F16/183

  Provision of network file services by network file servers, e.g. by using NFS, CIFS (network file access protocols H04L67/1097) · CPC title

• G06F11/2097

  maintaining the standby controller/processing unit updated (initialisation or re-synchronisation thereof G06F11/1658 and subgroups) · CPC title

• G06F11/1469 Primary

  Backup restoration techniques · CPC title

• G06F11/2094

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