Multi-Class Heterogeneous Clients in a Clustered Filesystem

• US 20100146045A1
• Filed: 11/10/2009
• Published: 06/10/2010
• Est. Priority Date: 06/05/2001
• Status: Active Grant

• Current Assignee: Hewlett Packard Enterprise Development LP (Hewlett-Packard Enterprise Company)
• Original Assignee: Silicon Graphics Incorporated (Graphics Properties Holdings, Inc.)
• Inventors: Moore, Daniel, Gildfind, Andrew
• Granted Patent: US 8,396,908 B2
• Time in Patent Office: Days
• US Class Current: 709/203
• CPC Class Codes: G06F 11/1448 Management of the data involved in backup or backup restore
• CPC Class Codes: G06F 11/1464 for networked environments
• CPC Class Codes: G06F 11/2069 Management of state, configuration or failover
• CPC Class Codes: G06F 16/128 Details of file system snapshots on the file-level, e.g. snapshot creation, administration, deletion use of snapshots for error detection or correction G06F11/14, G06F11/16
• CPC Class Codes: G06F 16/1827 Management specifically adapted to NAS management of storage area networks [SAN] G06F3/067
• CPC Class Codes: G06F 2201/805 Real-time
• CPC Class Codes: G06F 2201/82 Solving problems relating to consistency ensuring consistency in mirrored systems G06F11/2064
• CPC Class Codes: G06F 3/0617 in relation to availability
• CPC Class Codes: G06F 3/0619 in relation to data integrity, e.g. data losses, bit errors
• CPC Class Codes: G06F 3/065 Replication mechanisms
• CPC Class Codes: G06F 3/067 Distributed or networked storage systems, e.g. storage area networks [SAN], network attached storage [NAS]
• CPC Class Codes: H04L 41/0813 characterised by the conditions triggering a change of settings
• 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 69/329 in the application layer [OSI layer 7]
• CPC Class Codes: H04L 9/40 Network security protocols

Abstract

A cluster of computer system nodes connected by a storage area network include two classes of nodes. The first class of nodes can act as clients or servers, while the other nodes can only be clients. The client-only nodes require much less functionality and can be more easily supported by different operating systems. To minimize the amount of data transmitted during normal operation, the server responsible for maintaining a cluster configuration database repeatedly multicasts the IP address, its incarnation number and the most recent database generation number. Each node stores this information and when a change is detected, each node can request an update of the data needed by that node. A client-only node uses the IP address of the server to connect to the server, to download the information from the cluster database required by the client-only node and to upload local disk connectivity information.

Claims

1. A method for operating a cluster filesystem for a cluster connected by a storage area network, comprising:

receiving by a candidate node a periodic multicast of a cluster database server address and a database generation identifier from a cluster database server;

establishing by the candidate node a communication link with the cluster database server in response to the multicast cluster database server address and the database generation identifier;

requesting by the candidate node cluster information from the cluster database server to join the cluster, the cluster information including an address for at least one switch in the storage area network,

obtaining by the candidate node from the at least one switch at least one port address of at least one port connected to at least one host bus adapter of the candidate node;

sending the at least one port address and an address of the at least one host bus adapter from the candidate node to the cluster database server to update cluster configuration data concerning the cluster maintained by the cluster database server; and

requesting membership in the cluster by the candidate node.

2. The method of claim 1, further comprising the candidate node

obtaining cluster configuration data in response to requesting membership in the cluster;

and

configuring kernel components of the candidate node to enable access to the storage area network by the candidate node upon acceptance as a member of the cluster.

3. The method of claim 2, further comprising:

obtaining membership in the cluster;

receiving the periodic multicast;

comparing the cluster database server address and the database generation identifier of the periodic multicast to that stored in the candidate node;

requesting new cluster configuration data from the cluster database server in response to a mismatch in the cluster database server address or the database generation identifier.

4. The method of claim 2, further comprising:

maintaining the cluster configuration data at the candidate node.

5. The method of claim 1, further comprising:

configuring kernel components of the candidate node to create and accept connections to and from other nodes in the cluster.

6. The method of claim 1, further comprising:

providing authentication information upon requesting membership in the cluster.

7. The method of claim 1, further comprising:

obtaining membership in the cluster;

mounting and accessing filesystems on shared storage devices in the storage area network.

8. A computer readable medium including code for operating a cluster filesystem for a cluster connected by a storage area network, the code operable to:

receive by a candidate node a periodic multicast of a cluster database server address and a database generation identifier from a cluster database server;

establish by the candidate node a communication link with the cluster database server in response to the multicast cluster database server address and the database generation identifier;

request by the candidate node cluster information from the cluster database server to join the cluster, the cluster information including an address for at least one switch in the storage area network,

obtain by the candidate node from the at least one switch at least one port address of at least one port connected to at least one host bus adapter of the candidate node;

send the at least one port address and an address of the at least one host bus adapter from the candidate node to the cluster database server to update cluster configuration data concerning the cluster maintained by the cluster database server; and

request membership in the cluster by the candidate node.

9. The computer readable medium of claim 8, the code further operable to:

obtain cluster configuration data in response to requesting membership in the cluster; and

configure kernel components of the candidate node to enable access to the storage area network by the candidate node upon acceptance as a member of the cluster.

10. The computer readable medium of claim 9, the code further operable to:

obtain membership in the cluster;

receive the periodic multicast;

compare the cluster database server address and the database generation identifier of the periodic multicast to that stored in the candidate node;

request new cluster configuration data from the cluster database server in response to a mismatch in the cluster database server address or the database generation identifier.

11. The computer readable medium of claim 9, the code further operable to:

maintain the cluster configuration data at the candidate node.

12. The computer readable medium of claim 8, the code further operable to:

configure kernel components of the candidate node to create and accept connections to and from other nodes in the cluster.

13. The computer readable medium of claim 8, the code further operable to:

provide authentication information upon requesting membership in the cluster.

14. The computer readable medium of claim 8, the code further operable to:

obtain membership in the cluster;

mount and access filesystems on shared storage devices in the storage area network.

15. A system for operating a cluster filesystem for a cluster connected by a storage area network, comprising:

means for receiving by a candidate node a periodic multicast of a cluster database server address and a database generation identifier from a cluster database server;

means for establishing by the candidate node a communication link with the cluster database server in response to the multicast cluster database server address and the database generation identifier;

means for requesting by the candidate node cluster information from the cluster database server to join the cluster, the cluster information including an address for at least one switch in the storage area network,

means for obtaining by the candidate node from the at least one switch at least one port address of at least one port connected to at least one host bus adapter of the candidate node;

means for sending the at least one port address and an address of the at least one host bus adapter from the candidate node to the cluster database server to update cluster configuration data concerning the cluster maintained by the cluster database server; and

means for requesting membership in the cluster by the candidate node.

16. The system of claim 15, further comprising the candidate node

means for obtaining cluster configuration data in response to requesting membership in the cluster;

and

means for configuring kernel components of the candidate node to enable access to the storage area network by the candidate node upon acceptance as a member of the cluster.

17. The system of claim 16, further comprising:

means for obtaining membership in the cluster;

means for receiving the periodic multicast;

means for comparing the cluster database server address and the database generation identifier of the periodic multicast to that stored in the candidate node;

means for requesting new cluster configuration data from the cluster database server in response to a mismatch in the cluster database server address or the database generation identifier.

18. The system of claim 16, further comprising:

means for maintaining the cluster configuration data at the candidate node.

19. The system of claim 15, further comprising:

means for configuring kernel components of the candidate node to create and accept connections to and from other nodes in the cluster.

20. The system of claim 15, further comprising:

means for obtaining membership in the cluster;

means for mounting and accessing filesystems on shared storage devices in the storage area network.