DELAY_APPLY Configuration Parameter

Use the DELAY_APPLY configuration parameter to configure RS secondary servers to wait for a specified period of time before applying logs.

onconfig.std value
DELAY_APPLY 0
default value
0
values
0 = Apply logs
-1= Stage log files and apply data immediately.
A number followed by a time unit: for example, 1H sets the delay to one hour.
number: -1-999 = Number of days, minutes, hours, or seconds to wait.
time_unit: D, H, M, or S, where D = Days, H = Hours, M = Minutes, and S = Seconds. Values are not case sensitive.
takes effect
After you edit your onconfig file and restart the database server.
When you reset the value dynamically in your onconfig file by running the onmode -wf command.
When you reset the value in memory by running the onmode -wm command.

Usage

Delaying the application of log files allows you to recover quickly from erroneous database modifications by restoring the data from the RS secondary server. When setting the value of DELAY_APPLY you must also set LOG_STAGING_DIR. If DELAY_APPLY is configured and LOG_STAGING_DIR is not set to a valid and secure directory, then the server cannot be initialized.

You must specify a valid and secure location for the log files by setting the LOG_STAGING_DIR configuration parameter. The logs in the staging directory are purged after the last checkpoint has been processed on the RS secondary server.

To see information about the data being sent to the log-staging directory set for a RS secondary server, run the onstat -g rss verbose command on the RS secondary server.

If the write to the staging file fails, the RS secondary server raises event alarm 40007.

If a remote stand-alone secondary (RSS) server has its DELAY_APPLY configuration parameter set to a value other than 0, that server cannot use cluster transaction coordination.


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