Recommended information

Here's some best practices and recommended information for using Discovery.

Do not use the Discovery/scans folder as import folder

If you are using the Discovery Tool on the same server that is running your Jira/Assets service (we do not recommend that), then do not use the scans folder of the Discovery Tool as the import folder.

The import function will create subfolders and handle the imported files in the import folder, which will be in conflict with the Discovery-Tool logic.

Simply create a separate import folder on the server and let Discovery copy the result files to that folder.

Error messages when setting up Discovery or Collector

The interface is unknown. (Exception from HRESULT: 0x800706B5)

• If the machine hosting your Discovery installation is running Windows Server 2008 R2, the likely explanation for the problem is the absence of this patch on your Discovery server. Windows Server 2008 R2 has some known issues. Make sure Service Pack 1 is installed and the aforementioned patch is applied as well.
• If the machine hosting your Discovery installation is not running Windows Server 2008 R2 and the scanning errors are limited to specific Windows computers, it is also possible that WMI (Windows Management Instrumentation) is corrupt on those client machines. Follow the instructions on the destination server to fix that issue:

• • Run repairwmi.cmd on the client machine that's generating the WMI corruption errors. It recompiles all .mof WMI files found in the %windir%\System32\Wbem\Repository folder.
  • Execute the commands below on the client machine that's generating the WMI corruption errors.
    Winmgmt.exe /standalonehost
Winmgmt.exe /resetrepository
• If the script shows that wmidiag is missing then you can get it here Microsoft WMIDIAG Download

Missing Product results from Windows Server 2003

In Windows 2003 Server, Win32_Product is not enabled by default, and must be enabled as follows:

1. In Add or Remove Programs, click Add/Remove Windows Components.
2. In the Windows Components Wizard, select Management and Monitoring Tools and then click Details.
3. In the Management and Monitoring Tools dialog box, select WMI Windows Installer Provider and then click OK.
4. Click Next.

Usage of parallel threads

You will get the best scan performance by using two threads per CPU-Core.

For example 2 Cores = 4 Threads, 4 Cores = 8 Threads and so on.

Using more then two threads per core will not increase the scan performance.

Multiple Discovery Instances

It is possible to use multiple Instances of the Discovery-Tool, but it is not recommended.

If the instances executing scans at the same time it can affect the performance of the scans.

Also it is possible to create memory leaks and affect the system performance.

It will be more effective to use one instance with multiple scan settings and using parallel threads.

Overlapping Scheduled Scan-Settings

Scan-Settings can not overlap.

If one Setting is executing and another Setting reaches the scheduled time it will start after the running Setting is finished.

Scanning huge amount of destination Systems

If you reaching the maximum of scannable systems with all possibility's of

split up Scan-Setting over the day and using 2 threads per CPU-Core

then you need to create another discovery server to spread the "load" to different scan-systems.

(Do not create multiple Discovery Instances on the same server)

Maximum amount of "scannable" systems per day

As the required time for a scan depend on many various factors

(e.g. WMI needs more execution time, how many applications are installed, custom pattern, available CPU-Cores, etc.)

that we can just provide some example calculations and you need to figure out what are your limits in your environment.

The following calculations are based on the experience of average required time for:

Rough calculations for example environments: