SGD uses several timeouts when starting applications. The following timeouts are available:
None of the timeouts, apart from the Execution Protocol Engine timeout, apply when starting a Microsoft Windows application.
The Expect timeouts are defined in the
vars.exp
login script. The following table
lists the available Expect timeouts and their default values.
Timeout | Default Value |
---|---|
| 30 seconds |
| 40 seconds |
| 20 seconds |
If an Expect timeout expires, the script attempts to guess the prompt, and then continues to start the application.
The timeouts(hostprobe)
timeout is called by
the unix.exp
login script. This is the time
to wait for a response from the ttahostprobe
binary. The ttahostprobe
binary is used to
check whether an application server is available.
The ttahostprobe
binary outputs its response
to standard output (stdout
), and returns
y
for success or n
for
failure.
The time allowed for each Expect command to match a required string during the login phase.
For example, after the connection is made to the application server, the script has 40 seconds by default to match the login prompt before it times out. Every successful match resets the timer. During a login, the timeout is usually reset for the login prompt, the password prompt, and the shell prompt.
Increasing this timeout increases the time allowed for each phase of the login. This timeout must be large enough to allow for the longest phase of the login to be completed.
If the timeout expires, the script assumes that it is logged in
and has failed to match the shell prompt and sends echo
SYNC
to the application server to guess the prompt
string. If the user is not logged in when the timer fires, the
application fails to start. Otherwise, the shell prompt is set
to whatever the application server sent immediately after the
echo SYNC
and the application startup
continues.
If you see echo SYNC
and the shell prompt
ends in the normal way with $
,
%
, #
, or
>
, the
timeouts(prelogin)
value is too short.
The time allowed for each Expect command to match a required string once the user is logged in.
If the timeout expires, the script moves on to the next command. This can cause commands to be sent before the prompt has returned.
The most common occurrence of this timeout is if the script incorrectly sets the shell prompt. By default, this causes each command to wait 20 seconds before moving to the next command and can trigger one of the client timers.
Client timers are set using the clienttimer
Tcl command (see
Section E.2.2, “
clienttimer
”). If a client
timer expires, the application start is canceled with a fatal
ErrApplicationServerTimeout
error.
The client timers are defined in the
vars.exp
login script.
The following table lists the available client timers and their default values.
Timer | Default Value |
---|---|
|
|
| 40 seconds |
| 40 seconds |
| 25 seconds |
| 5 seconds |
The total time for the complete login phase, from making the connection to receiving the first shell prompt.
The timers(login)
timer must be large enough
to cover all of the login phases. Each individual phase of the
login (login prompt, password prompt, shell prompt) might last
up to the number of seconds defined for the
timeouts(prelogin)
timeout. The value of this
timer must always be greater than
timeouts(prelogin)
Expect timeout.
If you increase the timeouts(prelogin)
Expect
timeout, increase the timers(login)
timer as
well so that the difference between them is never less than 10.
The total time from receiving the first shell prompt until all of the application server environment variables have been exported.
The total time from setting the last environment variable to starting the main application.
The total time taken to build the command line to be executed. This timer is only used when starting Windows applications that use the SCO Merge protocol.
The SCO Merge protocol is no longer supported and can only be used by legacy SGD Windows application objects.
The total number of client timers. Only change this setting if you add or remove a client timer.
The procs.exp
login script includes a
three-second timeout when issuing commands. This is defined in
the proc wait_for_prompt
procedure.
The Execution Protocol Engine has a default timeout of 180 seconds (three minutes). This timeout starts when the request to start an application is received and removed when the application startup has completed successfully. If it expires, the application startup is canceled. This timeout is specific to each SGD server.
Use the following command to change this timeout:
$ tarantella config edit \
--tarantella-config-execpeconfig-maxlaunchtime secs
Use the --array option with this command to change this timeout for all the SGD servers in the array.