Restarting IIS
Applies To: Windows Server 2003, Windows Server 2003 R2, Windows Server 2003 with SP1
You might need to restart Internet Information Services (IIS) before certain configuration changes take effect or when applications become unavailable. Restarting IIS is the same as first stopping IIS, and then starting it again, except it is accomplished with a single command. There are two ways to restart IIS:
Using IIS Manager.
Using the IISReset command-line utility.
Both methods allow you to stop, start, and restart IIS Internet services. The Restart IIS command in IIS Manager and the IISReset command-line utility do not restart the HTTP protocol stack (HTTP.sys) or Internet services outside of IIS. In previous versions of IIS, restarting IIS using the IISReset command-line utility was a common practice for recovering from an unresponsive application.
Restarting or stopping IIS, or rebooting your Web server, is a severe action. When you restart the Internet service, all sessions connected to your Web server (including Internet, FTP, SMTP, and NNTP) are dropped. Any data held in Web applications is lost. All Internet sites are unavailable until Internet services are restarted. For this reason, you should avoid restarting, stopping, or rebooting your server if at all possible. IIS 6.0 includes application pool recycling and several other features that provide alternatives to restarting IIS. For a list of features designed to improve IIS reliability and remedy the need to restart IIS, see "Alternatives to Restarting IIS" in this topic.
Note
Changes to the metabase can be lost when restarting IIS. To avoid losing metabase changes and to trigger history files that back up the metabase, use the SaveData method. For more information about the SaveData method, see "SaveData" in the Platform SDK on MSDN.
With IIS 6.0, the World Wide Web Publishing Service (WWW service) lives in the service host, Svchost.exe. The FTP, NNTP, and SMTP services and the IIS metabase, known as the IIS Admin service, lives in Inetinfo.exe. If the IIS Admin service terminates abnormally, IIS restarts automatically. This feature is known as Automatic Restart. Previously, in IIS 5.0, if the IIS Admin service terminated abnormally, both the WWW service and IIS Admin service had to be restarted because they shared the same application space. In IIS 6.0, if the IIS Admin service terminates abnormally, the WWW service does not go down because the IIS Admin service and the WWW service run in separate process spaces. In this case, the WWW service acknowledges that the metabase has terminated abnormally and checks to see if the IISReset command-line utility is configured on the IIS Admin service. If IISReset is configured on the IIS Admin service, IIS waits for the IIS Admin service to start again and reconnects the WWW service.
All of the Internet services listed below, if installed, are affected when you restart IIS. Not all of the services listed below are installed by default.
Service | Description |
---|---|
IIS Admin service |
This service manages all the services of IIS other than the WWW service (FTP, NMTP, and SMTP). |
WWW service |
This service provides Web connectivity between clients and Web sites. |
HTTP SSL service |
This service provides secure Web connectivity between clients and Web sites. |
FTP service |
This service provides FTP connectivity and administration through IIS Manager. |
SMTP service |
This service transports electronic mail across the network. |
NNTP service |
This service transports network news across the network. |
Important
You must be a member of the Administrators group on the local computer to perform the following procedure or procedures. As a security best practice, log on to your computer by using an account that is not in the Administrators group, and then use the runas command to run IIS Manager as an administrator. At a command prompt, type runas /User:Administrative_AccountName "mmc %systemroot%\system32\inetsrv\iis.msc".
Procedures
To restart IIS using IIS Manager
In IIS Manager, right click the local computer, point to All Tasks, then click Restart IIS.
In the What do you want IIS to do list, click Restart Internet Services on computername.
IIS attempts to stop all services before restarting. IIS waits up to five minutes for all services to stop. If the services cannot be stopped within five minutes, all IIS services are terminated, and IIS restarts. In addition, clicking End now forces all IIS services to stop immediately, and IIS is restarted.
Warning
If IIS is terminated before its services have stopped normally, data loss can result. If possible, back up your IIS configuration before restarting IIS. See Backing Up and Restoring the Metabase for information about backing up your IIS configuration.
Important
You must be a member of the Administrators group on the local computer to run scripts and executables. As a security best practice, log on to your computer by using an account that is not in the Administrators group, and then use the runas command to run your script or executable as an administrator. At a command prompt, type runas /profile /User:MyComputer\Administrator cmd to open a command window with administrator rights and then type cscript.exe ScriptName (include the script's full path and any parameters).
To restart IIS using the IISReset command-line utility
From the Start menu, click Run.
In the Open box, type cmd, and click OK.
At the command prompt, type iisreset /noforce computername, and press ENTER.
Note
The /noforce parameter is recommended as a safeguard against data loss in case the IIS services cannot all be stopped within the one minute timeout period. If you are certain that it is safe to force IIS to restart, you can omit the /noforce parameter. In addition, if you are logged on locally, the computername parameter is not required. If you are administering an IIS server remotely, the computername parameter is the NetBIOS name of the computer on which you wish to restart IIS.
IIS attempts to stop all services before restarting. The IISReset command-line utility waits up to one minute for all services to stop. If the services cannot be stopped within one minute, all IIS services are terminated, and IIS restarts.
Note
You can adjust the timeout value using the iisreset /timeout command.
The IISReset command-line utility has several options available. For more information about the options available with the IISReset command-line utility, open a command-prompt window, and type iisreset /? You can also search for "iisreset" in Windows Help.
Automatic Restart
Automatic Restart is enabled by default for the IIS Admin service and WWW service. If a process within either service terminates abnormally, the service restarts automatically. The WWW service restarts using the net start command. The IIS Admin service restarts using the iisreset command. These commands are issued internally without user intervention. You can disable Automatic Restart using the following procedures.
To disable restart of IIS Admin service
From the Start menu, right-click My Computer, and click Manage.
In the console tree, expand the Services and Applications node, and click Services.
Right-click IIS Admin Service, and click Properties.
Click the Recovery tab, and in the First failure, Second failure, and Subsequent failures list boxes, click Take No Action.
Click OK.
The following command can only be issued on the local machine.
To disable restart of IIS Admin service from the command line
From the Start menu, click Run.
In the Open box, type cmd, and click OK.
At a command prompt, type iisreset /disable, and press ENTER. This command disables IIS and prevents all iisreset calls from executing.
Note
To re-enable the IIS Admin service, at the command prompt, type iisreset /enable, and press ENTER.
To disable restart of the WWW service
From the Start menu, right-click My Computer, and click Manage.
In the console tree, expand the Services and Applications node, and click Services.
Right-click World Wide Web Publishing Service, and click Properties.
Click the Recovery tab, and in the First failure, Second failure, and Subsequent failures list boxes, click Take No Action.
Click OK.
Alternatives to Restarting IIS
If you have to restart IIS often because of a faulty application, consider debugging or rewriting the application. To ensure that your applications do not interfere with other services and cause the need to restart IIS, it is recommended that you enable the following:
Worker Process Isolation Mode in IIS 6.0: Worker process isolation mode is the default service mode in IIS. Worker process isolation mode delivers all the benefits of IIS 6.0 new architecture: robust application pooling, automated restarts, scalability, debugging, and precise performance tuning.
Recycling Worker Processes with IIS 6.0: In worker process isolation mode, IIS can be configured to periodically restart worker processes in an application pool, allowing you to manage precisely those worker processes that are faulty.
Configuring Rapid-Fail Protection in IIS 6.0: Worker process isolation mode can be configured so that if a particular application pool experiences consecutive multiple failures, the application can be automatically disabled, allowing for rapid-fail protection.
Enabling CPU Monitoring in IIS 6.0: CPU monitoring is a tool for monitoring and automatically shutting down worker processes that consume large amounts of CPU time.
Related Information
For more information about improving the performance of IIS network resources using related features like bandwidth throttling, HTTP Compression, and connection limits, see Administering Network Resources.
For more information about configuring IIS to run Web applications and how to deal with reliability issues caused by Web applications, see Configuring Servers for Applications.
For information about starting and stopping individual Web and FTP sites, see Starting and Stopping Web Sites.