. Zend Server includes a multi-faceted restart option that was designed to ensure maximum performance and availability of your server, or cluster.
This restart type performs a selective restart, restarting only the components that actually need to be restarted. For example, if you have changed a Job Queue component directive, restarting Zend Server from the toolbar will only restart the Job Queue daemon. The other Zend components will not be effected.
A smart restart is performed by clicking the Restart icon in the Zend Server toolbar .
Note:
Performing an unwarranted restart from the toolbar (i.e., when the Restart icon is dormant 
), results in a full restart with no loss of session or job related information.
This restart type performs a full server restart that includes the Web server, PHP, and Zend Server daemons, directly from the UI. In a cluster, the full restart is performed according to the selected restart strategy.
A full restart can be initiated in two ways:
button in the Action bar..This type of restart only restarts a specific Zend component daemon, and is performed from the Configurations | Components page by clicking the restart icon 
for the relevant component.
Important!
This restart triggers a restart of Session Clustering and removes all session data - please use with extreme caution.
Note:
Only applicable for Zend Deployment, Zend Java Bridge, Zend Job Queue, Zend Monitor and Zend Session Clustering.
In a clustered environment, to minimize the downtime of your cluster, you can execute an asynchronous restart of your cluster by either selecting to restart a certain percentage of your servers at a time, or by defining a specific amount of servers to be restarted at a time.
For example, in a cluster consisting of ten servers, selecting to restart 50% of your cluster will instruct Zend Server to ensure that a maximum of five servers is restarted at the same time. If you have elected to restart seven servers (by manually selecting them from the Servers list on the Administration | Servers page), Zend Server will only restart five servers as its first task, and as soon as a server vacates a slot, an additional server will begin to restart. This asynchronous process will terminate as soon as all the selected servers have finished to restart.
The restart strategy is configured on the Administration | Settings page. For more information, see Configuring Zend Server.
Zend Server allows you to determine whether to wait for all processes to be completed before restarting the Web server.
Note:
This setting can only be configured on an Apache Web server running on a Linux OS.
Version
Zend Server 6.3
Zend Server Online Help 6.3v02
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