In a networked computing cluster storage system and plurality of servers sharing files, in the event of server unavailability, transferring a floating IP network address from first server to second server to access area of data

• US 7,124,171 B1
• Filed: 05/23/2002
• Issued: 10/17/2006
• Est. Priority Date: 05/23/2002
• Status: Expired due to Term

• Current Assignee: Emc IP Holding Company LLC (Dell Technologies Inc.)
• Original Assignee: EMC Corporation (Dell Technologies Inc.)
• Inventors: McCann, Peter J.
• Primary Examiner(s): CHANNAVAJJALA, SRIRAMA T
• Application Number:
  US10/153,583
• Time in Patent Office: 1,608 Days
• Field of Search: 707 1- 3, 707 8- 10, 707100-102, 707200-205, 709218-219, 709225-230, 709200-223, 709/231, 709213-216, 710/5, 714/4, 713/150, 713/200
• US Class Current: 709/216
• CPC Class Codes: G06F 11/2028 eliminating a faulty processor or activating a spare
• CPC Class Codes: G06F 11/2035 without idle spare hardware
• CPC Class Codes: G06F 16/144 Query formulation
• CPC Class Codes: H04L 61/5061 Pools of addresses
• CPC Class Codes: H04L 67/1097 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 Class Codes: H04L 69/40 for recovering from a failure of a protocol instance or entity, e.g. service redundancy protocols, protocol state redundancy or protocol service redirection management of faults, events, alarms or notifications in data switching networks H04L41/06

Abstract

A highly available shared file system is described for use in computing environments. A floating network address can be associated with any one of a plurality of servers. The floating network address is associated with a first server. An area of data on a storage device is made available by the first server to be accessed by the other servers. The other servers then refer to the floating network address to access the area of data through the first server. If the first server becomes unavailable, the floating network address is transferred from the first server to a second server. The area of data is then made available by the second server to be accessed by the other servers. The other servers continue to access the area of data through the second server by referring to the floating network address.

Claims

1. In a networked computing cluster including a storage system and a plurality of servers in communication with the storage system, a method for sharing files in an area of data of the storage system, comprising:

providing a floating Internet Protocol (IP) network address that can be associated with any one of the plurality of servers, each server already having a respective individual network address different from the floating IP network address;

associating the floating IP network address with a first server of the plurality of servers;

making the area of data available by the first server to be accessed by the other servers of the plurality of servers upon reference by the other servers of the plurality of servers to the floating IP network address;

in the event that the first server becomes unavailable, (1) transferring the floating IP network address from the first server to a second server of the plurality of servers so that the first server is no longer associated with the floating IP network address and the second server is associated with the floating IP network address, and (2) making the area of data available by the second server to be accessed by the other servers of the plurality of servers upon reference by the other servers to the floating IP network address,

wherein the area of data includes a file system stored on a storage area of the storage system, and wherein;

(i) making the area of data available by the first server comprises executing, by the first server, a file system sharing routine including;

(a) attaching to the storage area of the storage system to obtain direct access to the storage area;

(b) locally mounting the file system stored on the storage area; and

(c) issuing an export command to cause the file system to be shared among the plurality of servers, the export command including the floating IP network address as the network address to be referred to by the servers when accessing the file system; and

(ii) transferring the floating IP network address comprises executing, by the second server, a failover routine including the above steps (a)–

(c) of the file system sharing routine.

2. The method of claim 1 wherein the first server also refers to the floating IP network address to access the area of data.

3. The method of claim 1 wherein the first server is an NFS server and the other servers of the plurality of servers are NFS clients.

4. The method of claim 3 wherein the step of making the area of data available by the first server to be accessed by the other servers of the plurality of servers comprises issuing by the first server an NFS export command to export the area of data.

5. The method of claim 4 wherein the step of referring by the other servers of the plurality of servers to the floating IP network address to access the area of data through the first server comprises issuing by the other servers an NFS mount command to mount the area of data at the floating IP network address.

6. The method of claim 5 wherein the step of making the area of data available by the second server to be accessed by the other servers of the plurality of servers comprises issuing by the second server an NFS export command to export the area of data.

7. In a networked computing cluster including a storage system, apparatus for sharing files in an area of data of the storage system, comprising:

a plurality of servers in communication with the storage system, each server having an individual network address;

a floating Internet Protocol (IP) network address that can be associated with any one of the servers, the floating IP network address being different from each of the individual network addresses of the plurality of servers, wherein the floating IP network address is associated with a first server of the plurality of servers;

the first server being capable of making the area of data on a storage device accessible to the other servers of the plurality of servers upon reference by the other servers of the plurality of servers to the floating IP network address;

a mechanism operative in the event that the first server becomes unavailable to (1) transfer the floating IP network address from the first server to a second server of the plurality of servers so that the first server is no longer associated with the floating IP network address and the second server is associated with the floating IP network address, and (2) make the area of data available by the second server to be accessed by the other servers of the plurality of servers upon reference by the other servers to the floating IP network address,

wherein the area of data includes a file system stored on a storage area of the storage system, and wherein;

(i) the first server is operative when making the area of data available to execute a file system sharing routine including;

(a) attaching to the storage area of the storage system to obtain direct access to the storage area;

(b) locally mounting the file system stored on the storage area; and

(c) issuing an export command to cause the file system to be shared among the plurality of servers, the export command including the floating IP network address as the network address to be referred to by the servers when accessing the file system; and

(ii) the mechanism, when transferring the floating IP network address, includes executing, by the second server, a failover routine including the above steps (a)–

(c) of the file system sharing routine.

8. The apparatus of claim 7 whereby the first server is also capable of referring to the floating IP network address to access the area of data.

9. The apparatus of claim 7 wherein the first server is an NFS server and the other servers of the plurality of servers are NFS clients.

10. The apparatus of claim 9 wherein the first server is capable of making an area of data on the storage device accessible to the other servers by issuing an NFS export command to export the area of data.

11. The apparatus of claim 10 whereby the other servers of the plurality of servers are capable of referring to the floating IP network address to access the area of data through the first server by issuing an NFS mount command at the floating IP network address.

12. The apparatus of claim 11 wherein the second server is capable of making the area of data on the storage device accessible to the other servers by issuing an NFS export command to export the area of data.