Control cycle length |
Specifies the time between consecutive health
checks. The value is specified in minutes and ranges from 1 to 60
minutes. Longer control cycles reduce the health monitoring load.
The disadvantage is that health conditions that occur during that
period are not detected until the next control cycle. For example,
if you have a health policy with a workload condition of 10,000 requests
associated to an application server and the value is specified as
60 minutes, the health controller checks every 60 minutes to determine
if the application server has served 10,000 requests. If 9,999 requests
are detected during a health check, and a new health check occurs
after another 60 minutes (the control cycle length), the server actually
serves more than 10,000 requests prior to a restart. |
Maximum consecutive restarts |
Specifies the number of attempts to revive an
application server after a restart decision is made. If this number
is exceeded, the assumption is that the operation failed and restarts
are disabled for the server. The value must be a whole number between
1 and 5, inclusive. |
Minimum restart interval |
Controls the minimum amount of time that must
elapse between consecutive restarts of an application server instance.
If a health condition for an application server is breached during
that time, the restart is set to a pending state. When the minimum
restart interval passes, the restart occurs. The value can range from
15 minutes to 365 days, inclusive. A value of 0 disables the minimum
restart value. |
Restart timeout |
Consists of the sequence of stop and start server actions. The
restart timeout value specifies how long to wait -from the triggering of the health policy- to
explicitly checking for a server stop. When the health policy is triggered, the restart timeout
value goes into effect and a stop command is issued. After being issued, the state of the stop is
not checked until the restart timeout is reached. At the end of the restart timeout, if the server
has not stopped, an agressive stop is issued so that the server stops quickly, without draining
sessions. A start command can then be executed to restart the server. If the length of time to start
and stop an application server is unusually high, set this value so that the restart action does not
time out. Always specify the value in minutes. The value can range from 1 minute to 60 minutes,
specified as a whole number. The default value for restart timeout is 5 minutes. |
Enable health monitoring |
Enables or disables the operation of the health
controller. When enabled, the health controller continuously monitors
the health policies in the system. You can disable the health controller
without removing the health policies from the system. |
Prohibited restart times |
Specifies the times and days of the week when
a restart of an application server instance is prohibited. Specify
the start and end times by selecting the hour and minute using a 24
hour clock, and by selecting the days of the week. You can specify
multiple time blocks, if needed. If you specify a start time and end
time, you must also specify at least one day of the week when these
intervals are prohibited. The block between the start time and end
time cannot cross the midnight boundary. If you need to specify a
time block of, for example, 10:00 PM to 1:00 AM, you need to specify
two time blocks, one from 22:00 to 23:59 and one from 00:00 to 01:00.
Click Add to add additional time constraints.
To
remove an existing constraint, select the check box next to the constraint
and click Remove. If the restart time breaches
a health condition , the restart is delayed until the prohibited time
interval passes.
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