Method for providing an Internet protocol address with a domain name server

• US 5,884,038 A
• Filed: 05/02/1997
• Issued: 03/16/1999
• Est. Priority Date: 05/02/1997
• Status: Expired due to Term

• Current Assignee: RPX Corporation
• Original Assignee: WhoWhere?, Inc.
• Inventors: Kapoor, Rupesh
• Primary Examiner(s): Geckil, Mehmet B.
• Application Number:
  US08/850,782
• Time in Patent Office: 683 Days
• Field of Search: 395/200.68, 395/200.65, 395/200.59, 395/200.56, 395/200.57, 395/675, 395/200.47
• US Class Current: 709/226
• CPC Class Codes: G06F 11/3433 for load management allocation of a server based on load conditions G06F9/505; load rebalancing G06F9/5083; redistributing the load in a network by a load balancer H04L67/1029
• CPC Class Codes: G06F 11/3442 for planning or managing the needed capacity
• CPC Class Codes: G06F 2201/88 Monitoring involving counting
• CPC Class Codes: H04L 61/00 Network arrangements, protocols or services for addressing or naming
• CPC Class Codes: H04L 61/35 involving non-standard use of addresses for implementing network functionalities, e.g. coding subscription information within the address or functional addressing, i.e. assigning an address to a function
• CPC Class Codes: H04L 61/45 Network directories; Name-to-address mapping
• CPC Class Codes: H04L 67/1001 for accessing one among a plurality of replicated servers
• CPC Class Codes: H04L 67/1006 with static server selection, e.g. the same server being selected for a specific client
• CPC Class Codes: H04L 67/1008 based on parameters of servers, e.g. available memory or workload monitoring of computer activity G06F11/30
• CPC Class Codes: H04L 67/1019 Random or heuristic server selection
• CPC Class Codes: H04L 67/1034 Reaction to server failures by a load balancer
• CPC Class Codes: H04L 67/1038 Load balancing arrangements to avoid a single path through a load balancer

Abstract

A method for providing Internet protocol (IP) addresses with a domain name server (DNS) for multiple web servers of an Internet host. In one embodiment, each web server of an Internet host having multiple web servers is assigned a relative weight based on the individual processing power of the particular web server. As DNS resolution requests are received from client domains, the DNS returns IP addresses for the web servers such that the total number of times that each IP address of the web server is returned is proportional to the relative weight of each server relative to the total weight of all the servers. In another embodiment, the client domains that have most frequently accessed the web servers according to recent web server access logs are identified. In addition, the total number of accesses of each client domain is considered such that static arrays may be constructed to apportion the web servers among the client domains that most frequently access the web servers. As such, each of the client domains that most frequently access the web servers are assigned to a particular web server such that the percentage of requests served by each particular web server is proportional to the relative weight of that web server. In doing so, the probability of a load imbalance between the web servers is reduced.

Claims

1. In an Internet domain name server (DNS), a method of providing an Internet Protocol (IP) address of a first one of a plurality of servers of an Internet host, the method comprising the steps of:

receiving a DNS resolution request from a first one of a plurality of clients; and

returning to the first one of the plurality of clients the IP address of the first one of the plurality of servers such that a total number of times that the IP address of the first one of the plurality of servers is returned to the plurality of clients is proportional to a relative weight of the first one of the plurality of servers relative to a total weight of the plurality servers.

2. The method described in claim 1 including the additional steps of:

periodically determining whether each one of the plurality of servers is down;

setting to zero the relative weight of each one of the plurality of servers that is down; and

recalculating the total weight of the plurality of servers.

3. The method described in claim 2 including the additional step of informing the Internet host of each one of the plurality of servers that is down.

4. The method described in claim 1 including the additional steps of:

periodically determining whether each one of the plurality of servers is generating a time out error;

reducing the relative weight of each one of the plurality of servers that generate the time out error; and

recalculating the total weight of the plurality of servers.

5. The method described in claim 4 including the additional step of notifying the Internet host of each one of the plurality of servers that is generating the time out error.

6. The method described in claim 1 wherein the IP address of the first one of the plurality of servers is returned to the first one of the plurality of clients in a list including IP addresses of the other ones of the plurality of servers such that a total number of times that the IP address of the first one of the plurality of servers is at a top of the list when the list is returned to the plurality of clients is proportional to the relative weight of the first one of the plurality of servers relative to the total weight of the plurality servers.

7. In a domain name server (DNS), a method of providing an Internet Protocol (IP) address of one of a plurality of servers of an Internet host, the method comprising the steps of:

identifying a plurality of client domains that have recently requested to be connected to the plurality of servers;

apportioning the plurality of client domains among the plurality of servers such that a percentage of requests served by each one of the plurality of servers is proportional to a relative weight of each respective one of the plurality of servers;

receiving a DNS resolution request from a first requesting client of one of the plurality of client domains;

identifying said one of the plurality of client domains in which the first requesting client is included; and

returning to the first requesting client an IP address of one of the plurality of servers to which said one of the client domains was apportioned.

8. The method described in claim 7 wherein the step of apportioning the plurality of client domains among the plurality of servers includes the step of identifying a number of times each one of the plurality of client domains has recently requested being connected to the plurality of servers.

9. The method described in claim 8 wherein the step of identifying a number of times each one of the plurality of client domains has recently requested being connected to the plurality of servers includes the step of reading a recent server log of the Internet host.

10. The method described in claim 7 wherein the IP address of the one of the plurality of servers to which the one of the client domains was apportioned is returned to the first requesting client in a list including IP addresses of the other ones of the plurality of servers such that the IP address of the one of the plurality of servers to which the one of the client domains was apportioned is at a top of the list.

11. The method described in claim 7 including the additional steps of:

periodically determining whether each one of the plurality of servers is down;

setting to zero the relative weight of each one of the plurality of servers that is down; and

recalculating the total weight of the plurality of servers.

12. The method described in claim 11 including the additional step of notifying the Internet host of each one of the plurality of servers that is down.

13. The method described in claim 7 including the additional steps of:

periodically determining whether each one of the plurality of servers is generating a time out error;

reducing the relative weight of each one of the plurality of servers that generate the time out error; and

recalculating the total weight of the plurality of servers.

14. The method described in claim 13 including the additional step of notifying the Internet host of each one of the plurality of servers that is generating the time out error.

15. The method described in claim 7 including the additional steps of:

receiving a DNS resolution request from a second requesting client of a client domain not included in the plurality of client domains that have recently requested to be connected to the plurality of servers; and

returning to the second requesting client the IP address of a first one of the plurality of servers such that a total number of times that the IP address of the first one of the plurality of servers is returned is proportional to a leftover capacity of the first one of the plurality of servers relative to a total leftover capacity of the plurality servers.

16. The method described in claim 7 wherein the plurality of client domains that have recently requested to be connected to the plurality of servers include client domains that have recently frequently requested to be connected to the plurality of servers.

17. In a domain name server (DNS), a method of providing an Internet Protocol (IP) address of one of a plurality of servers of an Internet host, the method comprising the steps of:

determining a relative weight for each one of the plurality of servers;

calculating a total weight of the plurality of servers identifying a plurality of client domains that have recently frequently requested to be connected to the plurality of servers;

identifying a number of times each one of the plurality of client domains has recently connected to the plurality of servers

calculating a total number of times the plurality of servers has been connected to the plurality of client domains;

apportioning the plurality of client domains among the plurality of servers such that the relative weight of the first one of the plurality of servers in comparison to the total weight of the plurality servers is approximately proportional to a cumulative number of times each one of the plurality of client domains apportioned to the first one of the plurality of servers has recently connected to the plurality of servers in comparison to the total number of times the plurality of servers has been connected to the plurality of client domains;

receiving a DNS resolution request from a first requesting client of one of the plurality of client domains;

identifying said one of the plurality of client domains in which the first requesting client is included; and

returning to the first requesting client an IP address of one of the plurality of servers to which said the one of the client domains was apportioned.

18. The method described in claim 17 including the additional steps of:

receiving a DNS resolution request from a second requesting client of a client domain not included in the plurality of client domains that have recently frequently requested to be connected to the plurality of servers; and

returning to the second requesting client the IP address of a first one of the plurality of servers such that a total number of times that the IP address of the first one of the plurality of servers is returned is proportional to a leftover capacity of the first one of the plurality of servers relative to a total leftover capacity of the plurality servers.

19. The method described in claim 17 including the additional steps of:

periodically determining whether each one of the plurality of servers is down;

setting to zero the relative weight of each one of the plurality of servers that is down; and

recalculating the total weight of the plurality of servers.

20. The method described in claim 17 including the additional steps of:

periodically determining whether each one of the plurality of servers is generating a time out error;

reducing the relative weight of each one of the plurality of servers that generate the time out error; and

recalculating the total weight of the plurality of servers.