To specify the default flash (primary or secondary) to boot from on the next boot, use the
boot set-default flash command. The syntax is as follows:
boot set-default flash [ primary|secondary ]
switch(config)# boot set-default flash secondary
switch(config)# show flash
Image Size(Bytes) Date Version
------ ---------- ------- -------------
Primary Image : 7476770 03/15/10 K.15.01.0001
Secondary Image : 7476770 03/15/10 K.15.01.0001
Boot Rom Version: K.15.08
Default Boot : Secondary
switch(config)# boot
This management module will now reboot from secondary
and will become the standby module! You will need to
use the other management module's console interface.
Do you want to continue [y/n]?