%META:TOPICPARENT{name="UDATroubleshootingResources"}%

==Using Evidence to Diagnose Problems==

===Understanding Exit Codes Signals===

When a Broker or agent is terminated, the exit code can be seen in the log file (for example oplrqb.log) or in the foreground window.

The exits codes are shown below:

Table: 1. Log Levels 

|**Exit Code**| 	**Category**| 	**Comment**|
|0 	|NORMAL |	Normal exit with success|
|1 	|WARNING| 	some kind of failure at startup/shutdown, typically shown with a reason for this error|
|>1 	|UNKNOWN| 	When the exit code is not in the range of 0-15 then it is typically an uninitialised exit value taken from the stack. This can occur when an error in some database code is returned to the <nop>OpenLink code (Broker).|

The agent or broker may be terminated with a signal:

Table: 2. Reported Signals 

|**Signal** |	**Name** |	**Category** |	**Comment**|
|2 |	SIGINT|	NORMAL |	user pressed CTRL-C on oplrqb -fd|
|3 |	SIGQUIT| 	NORMAL| 	user pressed CTRL-\ on oplrqb -fd|
|4 |	SIGILL |	FAULT |	illegal instruction resulting in a program crash|
|7 |	SIGBUS| 	FAULT |	misaligned mem read/write resulting in a program crash|
|8 |	SIGFPE |	FAULT |	divide by 0 or other arithmetical error|
|9 |	SIGKILL |	NORMAL |	sent by the broker to kill an agent which has ignored multiple SIGTERMs|
|11| 	SIGSEGV |	FAULT| 	buffer/stack overrun resulting in a program crash|
|13 |	SIGPIPE 	|NORMAL |	other side of a pipe was killed while this side tried to write data to it|
|15 |	SIGTERM |	NORMAL| 	sent by the broker to an agent to ask it to terminate|

On the Windows platform, severe errors are reported in the following way:

{{{
pid ... died with status code 0x....
}}}

The hex number may be looked up in the winnt.h file. All errors reported in this way are considered severe, and should be reported to <nop>OpenLink Support.