FAILOVER IN A HOST CONCURRENTLY SUPPORTING MULTIPLE VIRTUAL IP ADDRESSES ACROSS MULTIPLE ADAPTERS

• US 20090158082A1
• Filed: 12/18/2007
• Published: 06/18/2009
• Est. Priority Date: 12/18/2007
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Lepakshaiah, Mallesh, Venkatsubra, Venkat, Murray, Elizabeth J., Jain, Vinit
• Granted Patent: US 7,913,106 B2
• Time in Patent Office: Days
• US Class Current: 714/4
• CPC Class Codes: H04L 61/103 across network layers, e.g. resolution of network layer into physical layer addresses or address resolution protocol [ARP]
• CPC Class Codes: H04L 69/18 Multiprotocol handlers, e.g. single devices capable of handling multiple protocols
• CPC Class Codes: H04L 69/40 for recovering from a failure of a protocol instance or entity, e.g. service redundancy protocols, protocol state redundancy or protocol service redirection management of faults, events, alarms or notifications in data switching networks H04L41/06

Abstract

A host enables any adapter of multiple adapters of the host to concurrently support any VIPA of the multiple VIPAs assigned to the host. Responsive to a failure of at least one particular adapter from among the multiple adapters, the host triggers the remaining, functioning adapters to broadcast a separate hardware address update for each VIPA over the network, such that for a failover in the host supporting the multiple VIPAs the host directs at least one other host accessible via the network to address any new packets for the multiple VIPAs to one of the separate hardware addresses of one of the remaining adapters.

Claims

1. A computer-implemented method for managing failover in a host supporting a plurality of virtual IP addresses on a network, comprising:

enabling any adapter of a plurality of adapters of the host to concurrently support any virtual internet protocol (IP) address of the plurality of virtual IP addresses assigned to the host; and

responsive to a failure of at least one particular adapter from among the plurality of adapters, broadcasting a separate hardware address update for each virtual IP address over the network from each remaining adapter from among the plurality of adapters, such that for a failover in the host supporting the plurality of virtual IP addresses the host directs at least one other host accessible via the network to address any new packets for the plurality of virtual IP addresses to one of the separate hardware addresses of one of the remaining adapters.

2. The method according to claim 1, wherein enabling any adapter of a plurality of adapters of the host to concurrently support any virtual internet protocol (IP) address of the plurality of virtual IP addresses assigned to the host further comprises:

configuring a network stack on the host to compare an IP address specified in an ARP request received at the host with a list of the plurality of virtual IP addresses to determine if the host supports the IP address in the list of plurality of virtual IP addresses.

3. The method according to claim 1, further comprising:

responsive to the host receiving an ARP request from a requesting host from among the at least one other host for a particular IP address matching a particular virtual IP address of the plurality of virtual IP addresses, triggering each of the plurality of adapters to send an ARP response to the requesting host with each hardware address of the adapter for the particular virtual IP address, wherein the requesting host stores one of the plurality of ARP responses from the plurality of adapters.

4. The method according to claim 1, further comprising:

responsive to the at least one other host receiving the plurality of updates, redirecting by the at least one other host a bound connection to one of the plurality of virtual IP addresses to a particular one of the separate hardware addresses of one of the remaining adapters.

5. The method according to claim 1, where the separate hardware address update for each virtual IP address over the network is a separate ARP update specifying a MAC address for each virtual IP address.

6. The method according to claim 1, wherein the host is a gateway between a subnetwork and at least one other network.

7. The method according to claim 1, further comprising periodically sending, by the host, a ping to the at least one other host comprising a gateway to determine if the gateway is functioning if the gateway returns a response to the ping.

8. A system for managing failover, comprising:

a host comprising a network layer for enabling any adapter of a plurality of adapters of the host to concurrently support any virtual internet protocol (IP) address of a plurality of virtual IP addresses assigned to the host;

the host communicatively connected over a network to at least one other host; and

the host further comprising the network layer, responsive to a failure of at least one particular adapter from among the plurality of adapters, for broadcasting a separate hardware address update for each virtual IP address over the network from each remaining adapter from among the plurality of adapters, wherein for a failover in the host supporting the plurality of virtual IP addresses the network layer directs the at least one other host accessible via the network to address any new packets for the plurality of virtual IP addresses to one of the separate hardware addresses of one of the remaining adapters.

9. The system according to claim 8, wherein the network layer for enabling any adapter of a plurality of adapters of the host to concurrently support any virtual internet protocol (IP) address of the plurality of virtual IP addresses assigned to the host further comprises:

a transport layer for configuring a network stack on the host to compare an IP address specified in an ARP request received at the host with a list of the plurality of virtual IP addresses to determine if the host supports the IP address in the list of plurality of virtual IP addresses.

10. The system according to claim 8, the host further comprising the network layer, responsive to the host receiving an ARP request from a requesting host from among the at least one other host for a particular IP address matching a particular virtual IP address of the plurality of virtual IP addresses, for triggering each of the plurality of adapters to send an ARP response to the requesting host with each hardware address of the adapter for the particular virtual IP address, wherein the requesting host stores one of the plurality of ARP responses from the plurality of adapters.

11. The system according to claim 8, further comprising the at least one other host, responsive to the at least one other host receiving the plurality of updates, for redirecting a bound connection to one of the plurality of virtual IP addresses to a particular one of the separate hardware addresses of one of the remaining adapters.

12. The system according to claim 8, where the separate hardware address update for each virtual IP address over the network is a separate ARP update specifying a MAC address for each virtual IP address.

13. The system according to claim 8, wherein the host is a gateway between a subnetwork and at least one other network.

14. The system according to claim 8, further comprising the host for periodically sending a ping to the at least one other host comprising a gateway to determine if the gateway is functioning if the gateway returns a response to the ping.

15. A program product comprising a storage-type computer-usable medium including a computer-readable program for managing failover in a host supporting a plurality of virtual IP addresses on a network, wherein the computer-readable program when executed on a computer causes the computer to:

enable any adapter of a plurality of adapters of the host to concurrently support any virtual internet protocol (IP) address of the plurality of virtual IP addresses assigned to the host; and

responsive to a failure of at least one particular adapter from among the plurality of adapters, broadcast a separate hardware address update for each virtual IP address over the network from each remaining adapter from among the plurality of adapters.

16. The program product according to claim 15, wherein the computer-readable program is transmitted over a network.

17. The program product according to claim 15, wherein the computer-readable program when executed on the computer further causes the computer to:

configure a network stack on the host to compare an IP address specified in an APP request received at the host with a list of the plurality of virtual IP addresses to determine if the host supports the IP address in the list of plurality of virtual IP addresses.

18. The program product according to claim 15, wherein the computer-readable program when executed on the computer further causes the computer to:

responsive to the host receiving an ARP request from a requesting host from among the at least one other host for a particular IP address matching a particular virtual IP address of the plurality of virtual IP addresses, trigger each of the plurality of adapters to send an ARP response to the requesting host with each hardware address of the adapter for the particular virtual IP address, wherein the requesting host stores one of the plurality of ARP responses from the plurality of adapters.

19. The program product according to claim 15, wherein the computer-readable program when executed on the computer further causes the computer to:

responsive to the at least one other host receiving the plurality of updates, redirect by the at least one other host a bound connection to one of the plurality of virtual IP addresses to a particular one of the separate hardware addresses of one of the remaining adapters.

20. The program product according to claim 15, wherein the computer-readable program when executed on the computer further causes the computer to:

update the separate hardware address update for each virtual IP address over the network through a separate ARP update specifying a MAC address for each virtual IP address.