PRTG Manual: Device Filters
When using UVexplorer, it is often necessary for you to select the devices that you are interested in from a list. For example, when adding or removing devices to/from a device group, you must select the devices to be added or removed. Similarly, when creating a manual link between two devices, you must select the devices to be linked. In these and many other situations, you will be asked to select devices from a device list. Since networks can contain hundreds or thousands of devices, searching through a list of all devices in the network can be overwhelming. Therefore, UVexplorer uses the notion of a ‘device filter’ to let you trim down a device list to display only the devices you are interested in. By default, UVexplorer displays all devices. However, using device filters, you can say things like, “Only show printers” or “Only show routers and switches”. This makes it much easier to find the devices you are looking for.
UVexplorer has a few built-in device filters that are always available. Here are the default device filters:
▪‘All Devices’ – This filter displays all devices. In effect, this filter can be used to turn off filtering.
▪‘SNMP Devices’ – This filter displays all devices that have SNMP enabled on them. This includes all devices that responded to SNMP queries when they were discovered.
▪‘Network Devices’ – This filter displays all network devices, which are devices that form the infrastructure of your network. This includes devices such as routers, switches, and wireless access points.
You can also create custom device filters that represent subsets of devices that you frequently work with. For example, you could create device filters such as these:
▪‘Only show servers in the 192.168.3.0/24 subnet’
▪‘Only show wireless controllers and wireless access points’
▪‘Only show devices in the Sales VLAN’
You can create as many custom device filters as you like, and they will always be available to you when you are asked to select devices from a list.
When you create a custom device filter, you must give it a name. For example, the custom device filters above might have these names:
▪‘Core Servers’
▪‘Wireless Infrastructure’
▪‘Sales Devices’
Custom device filters let you filter devices based on the following criteria:
▪Host/System/NetBIOS Name (including wildcards)
▪IP Address (including address ranges and subnets)
▪Device Categories (e.g., ‘printer’, ‘router’, ‘server’, ‘wireless ap’, ‘virtual machine’, etc.)
▪VLAN Name (including wildcards)
▪SNMP Enabled (or not)
To manage your custom device filters, click the Device Filters icon on the Settings toolbar. This will display the Device Filters form. This form lets you add, configure, and delete custom device filters. A list of all existing device filters is displayed on the left side of the form. The right side of the form displays properties of the currently-selected device filter.
To create a new device filter, click on the Add icon (the plus sign) just above the device filter list on the left side of the form. Alternatively, you can right-click anywhere in the device filter list, and select Add from the context menu. This will cause a new device filter with a default name to be created and selected. You can then edit the properties of the new device filter on the right side of the form.
The properties of a device filter can be modified by first selecting it in the list of device filters. After it has been selected, the right side displays the various properties that can be edited. To help you visualize the filter’s properties, the Filter Summary field at the bottom of the form always displays a summary of the filter’s current properties. This Filter Summary uses a SQL-like syntax to display all of the current filter properties in one place. It is updated any time the filter properties are modified.
To create a device filter, you must first specify a name (which cannot be empty). Next, you must specify which devices match the filter. This is done in two steps:
1.Select a base set of devices that match the filter. The choices are: All Devices, SNMP Devices Only, and Network Devices Only. This selection defines which devices could potentially match the filter (i.e., devices outside the base set will not match the filter).
1.All Devices – Any device can match the filter
1.SNMP Devices Only – Only SNMP devices can match the filter
1.Network Devices Only – Only network devices can match the filter (routers, switches, wireless access points, etc.)
2.Starting with the base device set selected in step 1, you may optionally specify additional criteria to narrow down the base set even further. The following additional filtering criteria may also be specified:
2.Host/System/NetBIOS Name – You can specify one or more patterns to be matched against a device’s names. For example, the pattern fileserver will match any device that has a DNS host name, SNMP system name, or NetBIOS name with the value fileserver. You can also include wildcard characters in a name pattern. For example, the pattern *.acme.com will match any device with a name ending in .acme.com. In general, an asterisk * will match zero or more adjacent characters, and a question mark ? will match exactly one character. If any device name patterns are specified, a device’s names must match at least one of the name patterns in order to match the filter.
2.IP Ranges – You can specify one or more IP addresses to be matched against a device’s IP addresses. You can specify individual IP addresses, such as 172.16.3.25; ranges of IP addresses, such as 192.168.3.1 – 192.168.3.127; or IP subnets, such as 10.5.0.0/16. If any IP address constraints are specified, a device must have at least one IP address that matches at least one of the constraints.
2.Categories – You can specify one or more device categories to be included in the filter. A list of all possible device categories is presented for you to choose from. Simply check the device categories that should match the filter. For example, if you select the ‘printer’ category, then printer devices will match the filter. If any device categories are specified, a device must be in at least one of the selected categories in order to match the filter.
2.VLANs - You can specify that devices in particular VLANs should be included in the filter. This is done by listing one or more patterns to be matched against the names of a device’s VLANs. For example, the pattern Sales will match any device that is in the VLAN named Sales. You can also include wildcard characters in a VLAN name pattern. For example, the pattern Marketing* will match any device that participates in a VLAN whose name begins with Marketing. In general, an asterisk * will match zero or more adjacent characters, and a question mark ? will match exactly one character. If any VLAN patterns are specified, a device’s VLANs must match at least one of the patterns in order to match the filter.
2.OIDS - You can specify that devices with an OID matching the provided OID pattern should be included in the filter. An OID is an unique object identifier provided by the manufacturer of a device or asset. The first portion of an OID is specific for a vendor and often a model. Multiple OID patterns can be provided, separated by a space or comma. Wild card's of '*' and '?' can be used when specifiying a match pattern. In general, an asterisk * will match zero or more adjacent characters, and a question mark ? will match exactly one character. If any OID patterns are specified, a device’s OID must match at least one of the patterns in order to match the filter.
After modifying the properties of a device filter, there are two things you can do to make sure it is working correctly:
1.Review the Filter Summary
2.Click the Preview button, which will display a list of devices in the currently-open discovery result that match the filter
To delete an existing device filter, select it in the device filter list on the left side of the form, and then click the Delete icon (with the red X) just above the list. Alternatively, you can right-click on the device filter in the list, and select Delete from the context menu. The deleted device filter should disappear from the list.
