Plesk & IIS Application / Pools

[Jon L]

Can anyone shed some light on how Plesk sets up applications and application pools within IIS? Specifically;

- When installing Drupal via the official APS installer, a number of additional applications for the site are created within IIS for the Drupal "sites" folder (and numerous sub folders) and the "tmp" folder. Why and what is doing this?

- Sometimes separate application pools will be created for specific domains but I can't see any settings that are causing this nor any pattern as to when it happens. Though one cause *may* be adding an SSL certificate to the site.

The above has caused us a major issue recently, with files within the "sites" folder being inaccessible which was eventually resolved by deleting the additional applications that had been created. So there is an actual problem here and I'm hoping an explanation of the above points might provide me with some pointers for a permanent resolution.

If it helps, we're currently running Plesk 10.0.0 on Windows Server 2008 R2 with IIS 7.5.

 

[PavelV]

This is behavior by design:
Your subscription operates in some Application Pool. It can be shared pool like plesk(default)(2.0)(pool) or dedicated pool. Pool is working under specified user identity - IWAM_xxx. When you are trying to install APS application, Plesk parses APS meta description and provision it in IIS. For every URL mapping described in APS package Plesk creates application in IIS. By default all these applications should be in the same Application pool.

Sometimes separate application pools will be created for specific domains

- looks like you are talking about shared and dedicated pools. By default, all domains are created in shared pool, and if "Use dedicated pool" is enabled in service plan or explicitly enabled in hosting settings for domain - dedicated pool will be created for this subscription.


Additionally Plesk has the following logic: if site created in Application Pool with .NET version 2.0 (for example), then application requires another version of .NET. Plesk will create additional pool for exact version of .NET and this application will be hosted in new pool.
Anyway Identity user for both these pools will be the same so you shouldn't have any security issues here.

If your security issue will be reproduced - plesk check exactly:
* in which pool site hosted
* in which pool applicaiton hosted
* identity of both these pools
* file permissions (for which user permissions are set on file system)

 

[Jon L]

Thanks for the reply.

I really need to work out a way to re-create the full problem I'm seeing, but one thing I have noticed and re-created;

- Site is running Drupal, applications for /sites (and 3 sub folders) and /tmp. All are in shared application pool.
- Activate SSL on domain.
- Three of the applications are now running in a new dedicated application pool and the other two (the /sites/all folders) are still in the shared application pool.
- Subscription becomes unsynced from service plan. If you then sync the plan SSL is removed.

Is this the correct behavior?

 

[PavelV]

O, I understand. This is bug, and it was fixed in Plesk 10.2