The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 27, 2015
Filed:
Jun. 29, 2012
Hui Qu, Santa Clara, CA (US);
Hui Qu, Santa Clara, CA (US);
Juniper Networks, Inc., Sunnyvale, CA (US);
Abstract
Techniques are described for providing high availability during an in-service software upgrade (ISSU) of an appliance within a network device, e.g., a router, by running a pair of virtual machines on each of a primary appliance and a secondary appliance within the router. Examples of the appliances include a routing engine within a router, and a service physical interface card (PIC) within a forwarding engine of a router. An ISSU of the primary appliance may first upgrade the operating system instance of a secondary virtual machine, switch operation from a primary virtual machine to the secondary virtual machine, and then upgrade the operating system instance on the primary virtual machine. During the ISSU of the primary appliance, primary and secondary virtual machines on the secondary appliance provide high availability to the virtual machine on the primary appliance executing the original operating system.