Update the server, suddenly found some of the machine error, roughly described as follows
HTTP Error 503.2-service Unavailable
The value set by [email protected] is being exceeded.
....
Server IIS basically uses the default settings, in order to avoid the next time this kind of error, find the relevant configuration, improve IIS concurrency number setting
1. Modify the IIS application pool queue Length
In advanced settings, the queue length is modified to 65535
2. Modify Appconcurrentrequestlimit settings for IIS
The default value is 5000, which is modified to 50000 (or a larger value)
C:\windows\system32\inetsrv\appcmd.exe Set config/section:serverruntime/appconcurrentrequestlimit:50000
You can view this setting in%systemroot%\system32\inetsrv\config\applicationhost.config:
3. Modify the settings of the Processmodel>requestqueuelimit in Machine.config
Changed from the original default 5000 to 50000
<processmodel enable= "true" requestqueuelimit= "50000"/>
4. Modify the registry to adjust the number of simultaneous TCPIP connections supported by IIS 7
5. Restart the service, the settings take effect
net stop http & net start
Microsoft Official Reference article
Modifying the net Request Queue Limit
http://technet.microsoft.com/en-us/library/dd425294 (office.13). aspx
Microsoft.com Microsoft Official website IIS application pool configuration recommendations, application pool configuration item description
Managing, Tuning, and configuring application pools in IIS 7.0
Windows Server IIS Concurrent Request settings