The time (in seconds) since the entire system
was last re-initialized as a result of reload. The
initialization being system loaded and running with a system
image software on the first active supervisor (SUP). In High
Availibility (HA) capable system / System that provides
Supervisor module redundancy, this uptime indicates time
elapsed since the first active SUP was booted. This will not
change even if the active SUP goes down and stand-by takes
over as active.