Hitless software upgrades

• US 8,448,162 B2
• Filed: 12/27/2006
• Issued: 05/21/2013
• Est. Priority Date: 12/28/2005
• Status: Active Grant

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Foundry Networks LLC (Broadcom, Inc.)
• Inventors: Ramanathan, Rajiv, Talmor, Ron, Kao, Shao-Kong, Ho, Anthony, Rugge, Rudramahesh
• Primary Examiner(s): Wong, Don
• Assistant Examiner(s): Lee, Marina
• Application Number:
  US11/646,845
• Publication Number:
  US 20090279549A1
• Time in Patent Office: 2,337 Days
• Field of Search: 717/171, 717/176
• US Class Current: 717/171
• CPC Class Codes: G06F 8/61 Installation
• CPC Class Codes: G06F 8/65 Updates security arrangements therefor G06F21/57
• CPC Class Codes: G06F 9/4401 Bootstrapping security arrangements therefor G06F21/57

Abstract

Disclosed is a technique for facilitating software upgrade for a switching system comprising a first management processor and a second management processor and a set of one or more line processors, the techniques comprising receiving a signal to perform a software upgrade for a line processor from the set of line processors, and performing a software upgrade for the line processor without substantially affecting packet switching performed by the switching system.

Claims

1. A method performed by a network device having a processor, the method comprising:

receiving a signal to perform an upgrade;

responsive to receiving the signal, loading first software code to a first region of a random access memory (RAM);

responsive to receiving the signal, storing protocol information in a reserved region of the RAM, the protocol information related to protocol interaction involving the processor when the signal is received;

responsive to receiving the signal,

loading decompressed second software code to a second region of the RAM;

while the loading of the decompressed second software code is being performed, transmitting a first protocol control packet using the loaded first software code, the transmitting comprising using the protocol information; and

after the decompressed second software code has been loaded, transmitting a second protocol control packet using the loaded decompressed second software code.

2. The method of claim 1 wherein at least one of the first protocol control packet and the second protocol control packet transmitted from the network device is a keep-alive packet.

3. The method of claim 1 wherein the processor is located on a linecard of the network device, the linecard comprising one or more ports for receiving and transmitting packets.

4. The method of claim 1 wherein the signal is received from a second processor in the network device.

5. The method of claim 1 wherein the first software code comprises an operating system.

6. The method of claim 1 wherein the decompressed second software code enables Open System Incorporation (OSI) Layer 1 through Layer 7 functionality.

7. The method of claim 1 further comprising:

receiving a compressed software image for the upgrade;

decompressing the compressed software image to generate the first software code; and

storing the first software code in the reserved region of the RAM.

8. The method of claim 1 further comprising:

receiving a compressed software image for the upgrade, the compressed software image comprising the second software code.

9. A network device comprising:

a data processor component; and

a memory component; and

wherein the data processor component is configured to;

receive a signal to perform an upgrade;

responsive to receiving the signal, load first program code to a first region of the memory component;

responsive to receiving the signal, store protocol information in a pre-determined region of the memory component, the protocol information related to protocol interaction involving, the data processor component when the signal is received;

responsive to receiving the signal,

load decompressed second program code to a second region of the memory component;

while the loading of the decompressed second program code is being performed, transmit protocol control packets using the loaded first program code, the transmitting comprising using the protocol information; and

after the decompressed second program code has been loaded, transmit protocol control packets using the loaded decompressed second program code.

10. The network device of claim 9 wherein the first program code comprises an operating system.

11. The network device of claim 9 wherein the decompressed second program code enables Open System Incorporation (OSI) Layer 1 through Layer 7 functionality.

12. The network device of claim 9 wherein the data processor component is configured to:

receive a compressed image for the upgrade;

decompress the compressed image to generate the first program code; and

store the first program code in the pre-determined region of the memory component.

13. The network device of claim 9 wherein the data processor component is configured to:

receive a compressed image for the upgrade, the compressed image comprising the second program code.