The Sam360 Management Point gathers inventory from remote devices by querying the WMI service on the device to be scanned. If the WMI service is unavailable (e.g. Blocked by firewall, Service disabled, Access denied, Computer switched off etc.) the Management Point will attempt to gather inventory data using the ‘Remote Registry’ service.
If both services are unavailable, the Management Point attempts to connect to the ‘File Share’ service and the ‘Service Control Manager’ service on the remote device to help determine the state of the device. The Management Point also pings the remote device.
By combining the responses to each attempted connection, the Management Point determines the ‘Connection Status’ of the remote device. The ‘Connection Status’ has 8 possible values.
Connection Status | Description |
---|---|
Blank | No connection errors were encountered. The scan was successful. |
Access Denied | None of the credentials available to the Management Point had permission to remotely scan the target device |
Blocked by Firewall | The Management Point was unable to connect to the WMI and Remote Registry services on the target device. However, the Management Point was able to connect to the ‘Service Control Manager’ service or the ‘File Share’ service or it was able to ping the target device. This suggests the target device is switched on and contactable, but the WMI and Remote Registry services are blocked by Windows firewall or another firewall between the Management Point and the target device |
No Response | No response was received to communication attempts made by the Management Point. The target device may be switched off, on a different network that can’t be accessed by the Management Point or behind a firewall that blocks access to the WMI, ‘Remote Registry’, ‘File Share’, ‘Service Control Manager’ and Ping services. |
No Response – Host Unreachable | This is similar to the connection status ‘No Response’ with one difference. Ping has returned ‘Destination Host Unreachable’ when pinging the target device. This reduces the likelihood that the problem is caused by a firewall and increases the likelihood that the problem is related to networking issues. |
Possibly Decommissioned | This is similar to the connection status ‘No Response’ with one addition. According to Active Directory, the device has not been active for over 60 days. It is likely that the target device is no longer in use |
Name Not Found | The DNS server used by the Management Point does not have a record for the target device. An error of ‘Unsuccessful Address Resolution’ was returned when the target device was pinged. No IP address could be found for the target device. |
Error | An error has occurred when connecting to the target device. The most common error is that a certain activity has taken over its allowed time – e.g. Querying the network for the devices domain name (30 seconds), Attempting to connect to remote WMI service (15 seconds) etc. |
Resolving Scan Issues
The following table outlines how scan connectivity problems can be resolved.
Connection Status | Resolution |
---|---|
Access Denied | By default, the Management Point uses its ‘Primary Credentials’ to scan remote devices. It can be configured to use one or more sets of additional credentials if the ‘Primary Credentials’ do not have sufficient privileges on one or more of the target devices.
Option 1 Option 2 |
Blocked by Firewall | The target device appears to be switched on and contactable, but access to WMI and ‘Remote Registry’ services is blocked.
Option 1 Option 2 Option 3 Option 4 Option 5 |
No Response No Response – Host Unreachable Name Not Found Possibly Decommissioned |
The target device was not contactable. Ensure that it is turned on and can access the network.If the device is on a different network to the Management Point and traffic on ports 135,139 & 445 cannot traverse the networks, it may be necessary to install an additional Management Point on the target device network.If traffic on ports 135, 139 & 445 cannot be enabled between the Management Point and target device, Options 2, 3, 4 & 5 from the previous section can be used to gather inventory from the affected devices. |
Error | Rescan the affected device(s) If the error persists, detailed error information should be available in the devices ‘WMI status’ and ‘Registry status’ fields. If it is not simply a timeout error, contact Sam360 for further support. |
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