Reboot vs Restart

[Anthony Barkhuizen_1]

We have a B1000 running HP-UX 11.00 64bit. After having a mailbox communication problem we rebooted the server using shutdown -r 0. This did not resolve the problem. Then we shut down the server and started it again (Power Down) - and this resolved the problem. Question is : what is the diffs between restarting and Power cycling.
Thanx in advance.

[whiteknight]

Hi Anthony,

Please see this link for explanation the difference

http://www1.itrc.hp.com/service/cki/docDisplay.do?docLocale=en&docId=emr_na-c00920995-2


WK
please assign points

[tkc]

power cycling will hard reset all your hardware. you might have some issue with a hard disk which had been hung. a hard reset may have resulted the disk to be powered off and start spinning up again after the power cycle.

[Robert-Jan Goossens]

Anthony,

Are there any errors in the /var/adm/syslog/syslog.log file?

Robert-Jan

[Srinivas Thokala_1]

Anthony,

Restarting the system will recycle upto operating system level and power cycle will halt the system including MP and GSP levels, which is the bottom layer below OS. Power cycle clears any error logs reported earlier, if there is no problem with the H/W and comes up as clean.

-Srini

[Amit Parui]

The basic difference in restart or reboot and Power cycling is in case of restart we do it without shutting the power off rather then in case of power cycling.

When a system is hard booted all the peripherals attached to it is rechecked and in your case i suppose one of the h/w was dodgy and hence when you did a power cycle it worked, which wasn't done while a restart.

Hope thts clear !!!