AUTOMATIC NETWORK RECONFIGURATION UPON CHANGES IN DHCP IP ADDRESSES

• US 20080109539A1
• Filed: 11/07/2006
• Published: 05/08/2008
• Est. Priority Date: 11/07/2006
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Mahajan, Ajay K., Reddy, Hemlata N., McLaughlin, Charles A., Foster, Robert K.
• Granted Patent: US 7,953,830 B2
• Time in Patent Office: Days
• US Class Current: 709/221
• CPC Class Codes: H04L 41/0816 the condition being an adaptation, e.g. in response to network events
• CPC Class Codes: H04L 41/082 the condition being updates or upgrades of network functionality
• CPC Class Codes: H04L 41/0856 by backing up or archiving configuration information
• CPC Class Codes: H04L 41/0869 Validating the configuration within one network element
• CPC Class Codes: H04L 61/5014 using dynamic host configuration protocol [DHCP] or bootstrap protocol [BOOTP]
• CPC Class Codes: H04L 61/5053 Lease time; Renewal aspects

Abstract

Generally speaking, systems, methods and media for detection and network reconfiguration upon changes in dynamic host configuration protocol (DHCP) IP addresses are disclosed. Embodiments of a method may include setting a renew time and a rebind time of a DHCP configuration and establishing an IP address with a first DHCP server. Embodiments may also include, after passage of the renew time, transmitting a renew request to the first DHCP server at its IP address and, in response to failure to receive an acknowledgement message from the first DHCP server, determining if the first DHCP server IP address is still valid. Embodiments may also include, in response to determining that the first DHCP server IP address is not still valid, retrieving a second, different DHCP server IP address from a network change event signal and configuring a network adapter based on the second DHCP server IP address.

Claims

1. A method for reconfiguring a network, the method comprising:

setting by a client a renew time and a rebind time of a dynamic host configuration protocol (DHCP) configuration;

establishing by the client an IP address with a first DHCP server, the IP address having a specified lease time;

after passage of the renew time, transmitting by the client a renew request to the first DHCP server at its IP address;

in response to failure to receive an acknowledgement message from the first DHCP server, determining by the client if the first DHCP server IP address is still valid;

in response to determining that the first DHCP server IP address is not still valid, retrieving by the client a second, different DHCP server IP address from a network change event signal; and

configuring by the client a network adapter based on the second DHCP server IP address.

2. The method of claim 1, further comprising after configuring the network adapter with the second DHCP server IP address, transmitting by the client to the DHCP server a new information table.

3. The method of claim 1, wherein the renew time is thirty minutes or less, and wherein further the rebind time is thirty minutes or less.

4. The method of claim 1, wherein determining if the first DHCP server IP address is still valid comprises transmitting by the client a rebind request to the DHCP server at its IP address and awaiting a response for the rebind time.

5. The method of claim 1, wherein retrieving the second, different DHCP server IP address from the network change event signal comprises subscribing to the network change event signal.

6. The method of claim 1, wherein configuring the network adapter based on the second DHCP server IP address comprises updating registries of the client.

7. The method of claim 1, wherein configuring the network adapter based on the second DHCP server IP address comprises detecting a change in the IP address by comparing a stored last known value of the IP address with a current value of the IP address.

8. A computer program product comprising a computer-useable medium having a computer readable program, wherein the computer readable program when executed on a computer causes the computer to:

setting a renew time and a rebind time of a dynamic host configuration protocol (DHCP) configuration;

establishing an IP address with a first DHCP server, the IP address having a specified lease time;

after passage of the renew time, transmitting a renew request to the first DHCP server at its IP address;

in response to failure to receive an acknowledgement message from the first DHCP server, determining if the first DHCP server IP address is still valid;

in response to determining that the first DHCP server IP address is not still valid, retrieving a second, different DHCP server IP address from a network change event signal; and

configuring a network adapter based on the second DHCP server IP address.

9. The computer program product of claim 8, further comprising after configuring the network adapter with the second DHCP server IP address, transmitting to the DHCP server a new information table.

10. The computer program product of claim 8, wherein the renew time is thirty minutes or less, and wherein further the rebind time is thirty minutes or less.

11. The computer program product of claim 8, wherein determining if the first DHCP server IP address is still valid comprises transmitting a rebind request to the DHCP server at its IP address and awaiting a response for the rebind time.

12. The computer program product of claim 8, wherein retrieving the second, different DHCP server IP address from the network change event signal comprises subscribing to the network change event signal.

13. The computer program product of claim 8, wherein configuring the network adapter based on the second DHCP server IP address comprises updating registries of the client.

14. The computer program product of claim 8, wherein configuring the network adapter based on the second DHCP server IP address comprises detecting a change in the IP address by comparing a stored last known value of the IP address with a current value of the IP address.

15. A client computer system in communication with a network, the system comprising:

a network interface module having a registry to store an indication of an IP address for a DHCP server leasing a first IP address to the client computer system;

a DHCP client in communication with the network interface module to interact with DHCP servers, the DHCP client comprising a renew sub-module to generate renew requests and a rebind sub-module to generate rebind requests; and

a network monitor in communication with the DHCP client having an IP address change detector and an IP address change updater, the IP address change detector being adapted to detect a change in IP address for the DHCP server based on a network change event signal, and the IP address change updater being adapted to modify the stored indication of the IP address for the DHCP server based on a detected change in IP address by the IP address change detector.

16. The system of claim 15, wherein the client computer system is a bulk power controller.

17. The system of claim 15, wherein the client computer system is a flexible service processor.

18. The system of claim 15, wherein the network interface module is adapted to control a network adapter, and wherein further the registry is located in the network adapter.

19. The system of claim 15, wherein the renew sub-module generates renew requests based on a renew time of thirty minutes or less.

20. The system of claim 15, wherein the rebind sub-module generates renew requests based on a rebind time of thirty minutes or less.