What does "sysctrl: allowing debug enter" mean?

阿毛~

Document Audience:
SPECTRUM
Document ID:
72313
Title:
What does "sysctrl: allowing debug enter" mean?
Update Date:
Fri Dec 05 00:00:00 MST 2003
Products:
Ultra Enterprise 6000 System,  Ultra Enterprise 5000 System,  Ultra Enterprise 4000 System,  Ultra Enterprise 3000 System,  Sun Enterprise 6500 Server,  Sun Enterprise 5500 Server,  Sun Enterprise 4500 Server,  Sun Enterprise 3500 Server,  Midframe & Midrange Servers
Technical Areas:
Mouse,  Keyboard
Keyword(s):sysctrl stop-a keyswitch
Description:

Top

Problem Scenario :
This applies to Enterprise Server systems, Exx00, with a keyboard and mouse
attached. It describes what may have happened when a server is down or not
reachable, seems hung, and/or you see this message in /var/adm/messages :
sysctrl : allowing debug enter
Document Body:

Top

Resolution :
For systems with a keyboard and mouse attached, this may mean that the
STOP-A key was pressed, or the keyboard was unplugged from the system.
sysctrl is a kernel module that controls access to OBP from a running
system. It monitors the keyswitch position, and controls the use of L1-A,
stop-A, or break signals, depending on the keyboard configuration.
"Allowing debug enter" means that someone had issued an L1-A or equivalent
on your system, dropping it down to the OBP "ok>" prompt.  There is a
keyswitch on the sun4u architecture that you can set to the secure
position, which will prevent an L1-A from being issued until the keyswitch
is changed to some other position.  If an L1-A is issued while the key is
in the secure position, you will see the following message instead:
sysctrl: ignoring debug enter sequence
What follows are the results of some empirical testing on an E4500 platform:
Case 1: Press Stop A -> ok prompt -> type go immediately
Result : "sysctrl: allowing debug enter" message is generated in
/var/adm/messages.
Case 2: Press Stop A -> ok prompt -> type go after 2 mins
Result : "sysctrl: allowing debug enter" message is generated in
/var/adm/messages
Case 3: Unplug keyboard -> Plug back in immediately -> ok prompt -> type go
immediately
Result : "sysctrl: allowing debug enter" message is generated in
/var/adm/messages
Case 4: Unplug keyboard -> Plug back in after 2 mins -> ok prompt -> type
go immediately
Result : "sysctrl: allowing debug enter" message is generated in
/var/adm/messages.
Case 5: Unplug mouse -> Plug back in immediately
Result : No sysctrl messaging in /var/adm/messages. No effect on system status.
Case 6: Unplug mouse -> Plug back in after 2 mins
Result : No sysctrl messaging in /var/adm/messages. No effect on system status.
Case 7: Change the keyswitch to secure position -> Unplug keyboard
Result : Does not drop to the ok> prompt. "sysctrl: ignoring debug enter"
message logged in /var/adm/messages.
Case 8: Changing the keyswitch to secure position -> Press Stop-A
Result : Does not drop to the ok> prompt. "sysctrl" ignoring debug enter"
message logged in /var/adm/messages.


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