User guide

CMM Files Managing CMM Directory Content
page 4-8 OmniSwitch AOS Release 7 Switch Management Guide March 2015
Redundancy
CMM software redundancy is one of the switch’s most important fail over features. For CMM software
redundancy, two fully-operational CMM modules must be installed at all times. In addition, the CMM
software must be synchronized. (Refer to “Synchronizing the Primary and Secondary CMMs” on
page 4-18 for more information.)
When two CMMs are running one CMM has the primary role and the other has the secondary role at any
given time. The primary CMM manages the current switch operations while the secondary CMM provides
backup (also referred to as “fail over”).
Redundancy Scenarios
The following scenarios demonstrate how the CMM software is propagated to the redundant CMM In the
examples below, R represents the RUNNING-CONFIGURATION directory and C represents the certi-
fied directory.
Scenario 1: Booting the Switch
The following diagram illustrates what occurs when a switch powers up.
Powering Up a Switch
Scenario 2: Rebooting from the Working Directory
After changes to the configuration and image files are saved to the working directory, sometimes it is
necessary to boot from the working directory to check the validity of the new files. The following diagram
illustrates the synchronization process of a working directory reboot.
CR
R
1. Switch is pow-
ered up and boots
from the certified
directory which
becomes the run-
ning-configura-
tion.
2. The running-
configuration is
automatically syn-
chronized to the
secondary CMM.
CMM A CMM B