Originally Posted by linuxmantra
POST stop key sequence in solaris is STOP D and STOP A.
STOP D is for extensive POST diagnostic on the system hardware.
STOP A: Puts the system into the command entry mode for the Open boot PROM.
Can anyone make me understand clearly why we need to disable the abort sequence as a system admin?
To prevent simple keyboard unplug/plugin from crashing the system...
Yeah, a stupid issue - but it does come up occasionally. The first time I ran across this was about 1978 with a PDP-11... Unplugging the console and plugging it in again generates a break signal... and that caused the CPU to decide to halt.
It is the same thing on Solaris. Having the abort key available is good... while you are debugging a driver on a workstation - you sometimes have to interrupt the system because it got stuck.
But running a production server that way is downright dangerous to your job when accidental downtime costs real money.
MOST of the time, an accidental abort can be recovered from with the continue command. But the system has lost time - and there are occasions when it doesn't work. This causes clock jumps, and things that have a timeout on I/O can get really confused. So for a safer environment (not debugging drivers) disabling the abort is a good idea.