Cisco Nexus 1000V, Руководство по устранению неисправностей, Страница: 77 / 280

C H A P T E R
6-1
Cisco Nexus 1000V Troubleshooting Guide, Release 5.2(1)SV3(1.1)
OL-31593-01
6
High Availability
This chapter describes how to identify and resolve problems related to high availability, and includes the
following sections:
•
Information About High Availability, page 6-1
• Problems with High Availability, page 6-2
•
High Availability Troubleshooting Commands, page 6-5
Information About High Availability
The purpose of high availability (HA) is to limit the impact of failures—both hardware and software—
within a system. The Cisco NX-OS operating system is designed for high availability at the network,
system, and service levels.
The following Cisco NX-OS features minimize or prevent traffic disruption if a failure occurs:
•
Redundancy—Redundancy at every aspect of the software architecture.
• Isolation of processes—Isolation between software components to prevent a failure within one
process disrupting other processes.
•
Restartability—Most system functions and services are isolated so that they can be restarted
independently after a failure while other services continue to run. In addition, most system services
can perform stateful restarts, which allow the service to resume operations transparently to other
services.
• Supervisor stateful switchover—Active/standby dual supervisor configuration. The state and
configuration remain constantly synchronized between two Virtual Supervisor Modules (VSMs) to
provide a seamless and statefu1 switchover if a VSM failure occurs.
The Cisco Nexus 1000V system is made up of the following:
• Virtual Ethernet Modules (VEMs) running within virtualization servers. These VEMs are
represented as modules within the VSM.
•
A remote management component, such as VMware vCenter Server.
• One or two VSMs running within virtual machines (VMs).