Methods and apparatus for determining, verifying, and rediscovering network IP addresses

• US 6,195,706 B1
• Filed: 07/07/1998
• Issued: 02/27/2001
• Est. Priority Date: 07/07/1998
• Status: Expired due to Term

• Current Assignee: Data General Corp. (Dell Technologies Inc.)
• Original Assignee: EMC Corporation (Dell Technologies Inc.)
• Inventors: Scott, John A.
• Primary Examiner(s): Matar, Ahmad F.
• Assistant Examiner(s): WINDER, PATRICE L
• Application Number:
  US09/111,349
• Time in Patent Office: 966 Days
• Field of Search: 370/401, 370/254, 709/220, 709/245, 709/226, 709/222, 709/244, 709/223, 713/201
• US Class Current: 709/245
• CPC Class Codes: H04L 61/5014 using dynamic host configuration protocol [DHCP] or bootstrap protocol [BOOTP]
• CPC Class Codes: H04L 67/01 Protocols
• CPC Class Codes: H04L 67/14 Session management for real-time applications in data packet communications networks H04L65/1066
• CPC Class Codes: H04L 69/22 Parsing or analysis of headers
• CPC Class Codes: H04L 69/323 in the physical layer [OSI layer 1]
• CPC Class Codes: H04L 69/325 in the network layer [OSI layer 3], e.g. X.25 H04L69/16 takes precedence

Abstract

A method and apparatus for assigning a network address of a target server/host system in a network system having server/host systems interconnected by network links. The apparatus includes a first part residing in a management server/host system and a second part residing in the target server/host system and each part includes a plurality of network address sub-mechanisms and an address manager mechanism for controlling operation of the network address mechanisms. The network address mechanism include, for example, a setup wizard mechanism, a reverse address resolution protocol mechanism, a unit-cast address discovery mechanism and a dynamic host configuration protocol mechanism. The address manager mechanism directs the operation of the network address sub-mechanisms through three modes of operation designated as the address discovery mode, the address verification mode and the operation mode, using each network address sub-mechanism cooperatively and in its own mode of operation, and in certain instances concurrently, to obtain a network address, a subnetwork mask and a gateway address for the target server/host system.

Claims

1. For use in a network system including a plurality of server/host systems interconnected by network links, a method for assigning a network address of a target server/host system by operation of an address discovery/verification mechanism having a first part residing in a management server/host system and a second part residing in the target server/host system, the first and second parts of the address discovery/verification mechanism each including a plurality of network address sub-mechanisms, including a setup wizard mechanism, a reverse address resolution protocol mechanism, a unit-cast address discovery mechanism and an address manager mechanism for controlling operation of the network address mechanisms, comprising the steps of:

(A) when the manager server/host and the target server/host each include a including a dynamic host configuration protocol mechanism,

(1) attempting to assign a network address to the target server/host by operation of the dynamic host configuration protocol mechanism in the manager and target server/host systems,

(B) when the dynamic host configuration protocol mechanism assigns a network address to the target server/host,

(1) storing the network address in a static memory in the target server/host system, and

(2) disabling DHCP on the target server/host and

(3) going to step (F),

(C) when the dynamic host configuration protocol mechanism does not assign a network address to the target server/host system, initiating operation of the reverse address resolution protocol mechanism, the setup wizard mechanism and the unit-cast address discovery mechanism and concurrently

(1) transmitting reverse address resolution protocol requests and monitoring the network links for a reverse address resolution protocol response,

(2) monitoring the network links for a setup wizard configuration packet, and

(3) monitoring the network links for a uni-cast echo packet, and

(4) extracting a network address from the first received of a reverse address resolution protocol response, a setup wizard configuration packet and a uni-cast echo packet,

(D) comparing the network address received in step (C) with the network address in static memory and

(1) when the network address in static memory is the same as the network address received in step (C), go to step (G),

(E) when the network address in static memory is different from the network address received in step (C),

(1) store the network address received in step (C) and

(2) if the network address was received in setup wizard configuration packet, and

(3) when the setup wizard configuration packet contained a subnetwork mask and a default gateway address, going to step (F), and

(4) when the setup wizard configuration packet did not include a subnetwork mask,

(a) transmitting a ICMP address mask request to a network default broadcast address, and

(b) when a ICMP address mask response is received, extracting the subnetwork mask,

(c) when a ICMP address mask response is not received, reading a default mask stored in the target server/host system as the subnetwork mask,

(5) when the setup wizard configuration packet did not include a default gateway address,

(a) periodically and concurrently transmitting a router solicit message and a request message packet, and

(b) when a router advertisement message or a response message packet is received, extracting the default gateway address from the received router advertisement message or a response message packet, and

(F) storing the network address, the subnetwork address and the gateway address in a static memory in the target server/host system and reinitializing operation of the target server/host system and

(G) placing the target server/host system in the operating mode.

2. An address discovery/verification mechanism for use in a network system for assigning a network address of a target server/host system, the network system including a plurality of server/host systems interconnected by network links and the address discovery/verification mechanism comprising:

a first part residing in a management server/host system and a second part residing in the target server/host system,

the first and second parts of the address discovery/verification mechanism each including

a plurality of network address sub-mechanisms, including

a setup wizard mechanism, a reverse address resolution protocol mechanism, and a unit-cast address discovery mechanism,

an address manager mechanism for controlling operation of the network address mechanisms for executing the operating steps of

(A) initiating operation of the reverse address resolution protocol mechanism, the setup wizard mechanism and the unit-cast address discovery mechanism and concurrently

(1) transmitting reverse address resolution protocol requests and monitoring the network links for a reverse address resolution protocol response,

(2) monitoring the network links for a setup wizard configuration packet, and

(3) monitoring the network links for a uni-cast echo packet, and

(4) extracting a received network address from the first received of a reverse address resolution protocol response, a setup wizard configuration packet and a uni-cast echo packet,

(B) verifying the received network address by

(1) extracting a next received network address from the next received of a setup wizard configuration packet, a uni-cast echo packet and a hypertext transfer packet, and

(2) comparing the next received network address with the received network address, and

(3) when the next received network address is different from the received network address, returning to step (A),

(C) when the next received network address is the same as the received network address and the received network address was received in setup wizard configuration packet, and

(1) when the setup wizard configuration packet contained a subnetwork mask and a default gateway address, going to step (D), and

(2) when the setup wizard configuration packet did not include a subnetwork mask,

(a) transmitting a ICMP address mask request to a network default broadcast address, and

(b) when a ICMP address mask response is received, extracting the subnetwork mask,

(c) when a ICMP address mask response is not received, reading a default mask stored in the target server/host system as the subnetwork mask,

(3) when the setup wizard configuration packet did not include a default gateway address,

(a) periodically and concurrently transmitting a router solicit message and a request message packet, and

(b) when a router advertisement message or a response message packet is received, extracting the default gateway address from the received router advertisement message or a response message packet, and

(D) placing the target server/host system in the operating mode by storing the network address, the subnetwork address and the gateway address in a static memory in the target server/host system and reinitializing operation of the target server/host system.

3. The address discovery/verification mechanism for use in a network system for assigning a network address of a target server/host system of claim 2, further comprising:

a dynamic host configuration protocol mechanism for

initially attempting to assign a network address to the target server/host by operation of the dynamic host configuration protocol mechanism in the manager and target server/host systems, and,

when the dynamic host configuration protocol mechanism assigns a network address to the target server/host, storing the network address in a static memory in the target server/host system,

initiating the address manager mechanism for controlling operation of the network address mechanisms for executing the operating step (D) of placing the target server/host system in the operating mode by storing the network address, the subnetwork address and the gateway address in a static memory in the target server/host system and reinitializing operation of the target server/host system, and

when the dynamic host configuration protocol mechanism does not assign a network address to the target server/host,

initiating operation of the reverse address resolution protocol mechanism, the setup wizard mechanism and the unit-cast address discovery mechanism and concurrently initiating execution of the operating steps of

(1) transmitting reverse address resolution protocol requests and monitoring the network links for a reverse address resolution protocol response,

(2) monitoring the network links for a setup wizard configuration packet, and

(3) monitoring the network links for a unicast echo packet, and

(4) extracting a received network address from the first received of a reverse address resolution protocol response, a setup wizard configuration packet and a uni-cast echo packet.