User guide

Managing CMM Directory Content CMM Files
OmniSwitch AOS Release 7 Switch Management Guide March 2015 page 4-5
Changes made to the RUNNING CONFIGURATION will immediately alter switch functionality.
However, these changes are not saved unless explicitly done so by the user using the write memory
command. If the switch reboots before the RUNNING CONFIGURATION is saved, then the certified
directory is reloaded to the RUNNING CONFIGURATION and configuration changes are lost.
New image or configuration files should always placed in the working or or a user-defined directory first.
The switch can then be rebooted from that directory and be tested for a time to decide whether they are
reliable. Once the contents of that directory are established as good files, then these files can be saved to
the certified directory and used as the most reliable software to which the switch can be rolled back in an
emergency situation.
Should the configuration or images files prove to be less reliable than their older counterparts in the certi-
fied directory, then the switch can be rebooted from the certified directory, and “rolled back” to an earlier
version.
Software Rollback Configuration Scenarios
The examples below illustrate a few likely scenarios and explain how the RUNNING CONFIGURA-
TION, user-defined, working, and certified directories interoperate to facilitate the software rollback on a
single switch.
In the examples below, R represents the RUNNING CONFIGURATION, W represents the working
directory, and C represents the certified directory.
Scenario 1: Running Configuration Lost After Reboot
Switch X is new from the factory and performs a cold reboot booting from the certified directory. Through
the course of several days, changes are made to the RUNNING CONFIGURATION but not saved to a
directory.
Power to the switch is interrupted, the switch reboots from the certified directory and all the changes in
the RUNNING CONFIGURATION are lost since they weren’t saved.
This is illustrated in the diagram below:
Running Configuration is Overwritten by the Certified Directory on Reboot
RWC
RWC
RWC
RWC
1. Switch boots
from certified
directory.
2. Changes are
made to the run-
ning configura-
tion but not saved.
3. Power is inter-
rupted and the
switch reboots.
4. Switch reboots
from certified and
all running config-
uration changes
are lost since they
weren’t saved or
certified.