A consultant is telling us to reboot our system
(Alphaserver ES40, Tru64 V4.0G) monthly and seems to
be locked into the terminology "hard boot" and
"soft boot." "Hard boot" is being taken to mean
shutting down and turning off the power for some
period of time. He says,
"...a soft reboot does not necessarily clear all your ghost
threads and ports. Operating systems can still hold on to
these ghost threads, hence making them unusable. However,
physically shutting down the server will certainly release
all of these ghost threads and free up any ports that might
be getting left open. Java uses a lot of different threads
during its normal execution. However, Unix was not
originally intended to run multi-threaded applications. For
this reason, Unix (just like Windows) can hold on to some of
these threads and not properly close them. That is where
physically shutting down the server comes in. I hope this
clarifies things a little more."
My position is that it is certainly not necessary to power
off the hardware when rebooting the system.
My position is also that regardless of whether we do
shutdown -r to reboot the system or shutdown -h to halt the
system, in both cases the operating system comes all the way
down and that we should not think of one as "soft" and the other
as "hard."
In fact, shutdown -r would be prefereable since it can be done
remotely or unattended, rather than the physical presence of
someone to type "boot" at the console prompt which would be
needed if we did shutdown -h.
Am I wrong?
Received on Thu Feb 20 2003 - 15:44:17 NZDT