Service providing system

Patent metadata

Field	Value
Publication number	US-9071612-B2
Application number	US-201213568682-A
Country	US
Kind code	B2
Filing date	Aug 7, 2012
Priority date	Oct 17, 2011
Publication date	Jun 30, 2015
Grant date	Jun 30, 2015

Abstract

In a system with a terminal sending a request, when a load distributing unit distributes the request to many service providing apparatuses, the load distributing unit becomes a bottleneck of performance and/or a single point of failure. When the load is distributed to the service providing apparatuses without using the load distributing unit, a particular function is required on the terminal side to appropriately select one of apparatuses. A name resolution unit including an address group management table with IP addresses to select, for a request from a terminal, an address from the table to return the address to the terminal and a plurality of service providing apparatuses to which at least zero IP address selected from the table is allocated without duplication are arranged such that each service providing apparatus is allocated with IP addresses according to processing performance thereof, thereby conducting appropriate load distribution.

First claim

The invention claimed is:

1. A service providing system comprising:
a plurality of service providing apparatuses and
at least one name resolution unit,
one of the service providing apparatuses responding to a service request from a terminal, wherein
the name resolution unit is configured to manage an address group including n IP addresses allocated to a service providing apparatus group including k service providing apparatuses (n is equal to or greater than k) and comprises a name resolution request processing section for selecting, in response to the service request from the terminal, one IP address from the address group managed by the name resolution unit, to thereby make a response,
each of the service providing apparatuses is allocated with m IP addresses (m is equal to or more than zero) selected from the n IP addresses managed by the name resolution unit, without duplication with respect to any other one of the service providing apparatuses, and comprises:
a terminal request processing section configured to provide, based on the response to the name resolution request, a service to the service request from the terminal, and
a load distributing function section configured to conduct load distribution of a load between the service providing apparatus and any one other of the service providing apparatuses, wherein
each of the plurality of the service providing apparatuses is configured to be a monitor-target service providing apparatus whose load is monitored by any one other of the service providing apparatuses as a monitoring service providing apparatus; and
the load distributing function section of the monitoring service providing apparatus is configured to move, when a high load is imposed on the monitor-target service providing apparatus, allocation of IP addresses from the monitor-target service providing apparatus to the monitoring service providing apparatus.

2. A service providing system according to claim 1 , wherein the load distributing function section of the monitoring service providing apparatus
is configured to transmit, in the moving of allocation of IP addresses, an address transfer request to the monitor-target service providing apparatus when the load on the monitor-target service providing apparatus is higher at least a predetermined value than a load on the monitoring service providing apparatus, and
register, at reception of an address transfer response including IP addresses as an object of the moving of allocation of IP addresses from the monitor-target service providing apparatus, the IP addresses included in the address transfer response, as IP addresses to be allocated to the monitoring service providing apparatus.

3. A service providing system according to claim 2 , wherein in response to the address transfer request, the load distributing function section of the monitor-target service providing apparatus is configured to select one of the IP address the in-charge IP addresses allocated to the monitoring service providing apparatus, delete allocation of the IP address thereto, and transmit the address transfer response, to thereby notify the response to the monitoring service providing apparatus.

4. A service providing system according to claim 1 , wherein
the IP addresses in the moving of allocation of IP addresses are IP addresses not being used,
the name solution unit is configured to manage an address group under control thereof by dividing the address group into at least two low-order groups, and
select, according to date and time, one of the low-order groups to which an address to be selected for the name resolution request from the terminal belongs.

5. A service providing system according to claim 1 , wherein
the load distributing function section of the monitoring service providing apparatus is configured to manage previous date and time when the allocation of IP addresses is moved from a monitor-target service providing apparatus to the monitoring service providing apparatus, and
move the allocation of IP addresses if difference between current date and time and the previous date and time is equal to or more than a predetermined value.

6. A service providing system according to claim 1 , wherein
the load distributing function section of the monitoring service providing apparatus
is configured to monitor each of the monitor-target service providing apparatuses in operation,
manage candidates of IP addresses of which allocation is moved from the monitor-target service providing apparatus to the monitoring service providing apparatus, and
register, if it is judged, as a result of monitoring, that failure has occurred in the monitor-target service providing apparatus, the candidates of IP addresses which are under control thereof and of which allocation is to be moved, as IP addresses to be allocated to the monitoring service providing apparatus.

7. A service providing system according to claim 6 , wherein
the k service providing apparatuses are divided into two groups comprising a group of service providing apparatuses in operation and a group of service providing apparatuses in a standby state, and
the load distributing function section of the monitoring service providing apparatus in operation
is configured to monitor each of the monitor-target service providing apparatuses in operation,
select, if it is confirmed that failure has occurred in the monitor-target service providing apparatus, one of the service providing apparatuses in the standby state, as a new monitor-target service providing apparatus, and
send, to the new monitor-target service providing apparatus, an address transfer response including the IP addresses allocated to the monitor-target service providing apparatus in which failure has occurred.

8. A server device group comprising:
a plurality of “k” (“k” shows plural) server devices respectively coupled to a network with a routing function;
each of the plurality of “k” server devices being configured to receive one access via the network, wherein
each of the plurality of “k” server devices is assigned at least one of “n” (“n” shows an integer greater than or equal to “0”) addresses, each of the addresses being different from each other capable of being assigned to any of one of the plurality of “k” server devices,
the server device group is configured to change a destination of assignment of 1 through (m−1) addresses out of “m” addresses, “m” showing an integer greater than or equal to “2”, having been assigned to a first server device toward a second server device with a lower load than the first server device, and
the second server device is configured to receive an access via the network directed to the 1 through (m−1) addresses having been assigned thereto.

9. The server device group according to claim 8 , wherein the second server device is further configured to send a notice of the change of assignment of addresses toward the routing function.

10. The server device group according to claim 9 , wherein used for the notice is a gratuitous ARP message.

11. The server device group according to claim 8 , further comprising a load monitoring function, wherein
the load monitoring function is configured to send an address taking over request toward the first server device in case that difference of loads between the first and second server devices is greater than or equal to a predetermined amount of value, and
the second server device is further configured to register thereto the 1 through (m−1) addresses on the basis of a response of the first server to the address taking over request.

12. The server device group according to claim 11 , wherein the first server device is configur

Assignees

• Toumura Kunihiko
• Takeshima Yoshiteru
• Haraguchi Naoki
• Hitachi Ltd

Inventors

• Toumura Kunihiko
• Takeshima Yoshiteru
• Haraguchi Naoki

Classifications

• H04L67/1031 Primary

  Controlling of the operation of servers by a load balancer, e.g. adding or removing servers that serve requests · CPC title

• H04L61/2007

  Electricity · mapped topic

• H04L61/1511

  Electricity · mapped topic

• H04L61/5007

  Internet protocol [IP] addresses · CPC title

• H04L61/4511

  using domain name system [DNS] · CPC title