Device Group Strings

The Group membership of a Device is controlled by the inclusion of keywords into that Device's Group String, which is stored in each device (under the MIB variable name <device-model>Groups ). The keywords and their meanings are entirely user-defined based on any convenient set of criteria, such as physical location, protocol type, department within your organization, or the names of your pet hedgehogs.

Each slide-in Device may have any number of user-defined group keywords as desired assigned to it, up to a maximum of 63 characters including spaces. Any printable character other than the wildcard character '*' may appear in a Device Group String. The characters '-', '!', '+', and '.' should be avoided since they have special meaning when they appear at the beginning of a keyword. See the section on Group Control Strings for more information.

When the Group Control String is not blank, then the Cabinet and Slot values in a standard SNMPv1 request that uniquely identify a particular Device in the stack are ignored, and the change is instead applied to all devices that have keywords in their Device Group Strings that match the Group Control String.

Devices of various models may be mixed in a group. However, any single group configuration change can affect only one model of Device at a time since there are no configuration attributes that can be applied to multiple different models of Device. So, for example, you could assign 35 10Mbps (CETTF100) and 40 100Mbps (CFETF100) Twisted-Pair to Fiber Ethernet converters to belong to the "ELBOW" group. To turn link passthrough off on all 75 devices, you would need to make two configuration changes: 1) Turn link passthrough off on all CETTF100 devices in the "ELBOW" group, 2) Turn link passthrough off on all CFETF100 devices in the "ELBOW" group.

In addition to any user-defined group keywords that are assigned, each slide-in device has three automatically-defined group keywords:

1. The model family of the device (e.g. "CPSMM100" for the base management module) This allows a particular feature to be set exactly the same way for every device of a particular model in the entire Point System stack.

2. The serial number of the cabinet into which the device is installed (as shown in the main Focal Point menu and every Cabinet View Screen). This allows changes to be applied to all devices of a particular model in a single cabinet.

3. The serial number and slot number where the device is installed (e.g. "13046[4]" for cabinet serial 13046, slot 4.) This is useful for copying a configuration from one slot to another.

For an example of the use of these automatically defined keywords, see Copying a Device Configuration from one slot to another .

Due to the limited available data storage on Point System Slide-In devices, they contain no separate user-defined "Description" fields. However, descriptive keywords may be placed into a Device Group String even if one has no intention of using the keywords in conjunction with the Configuration Management feature. In this way, a description can be assigned to a particular device. If the Device Group string is used in this way, it is highly recommended that punctuation marks be used carefully, since (as described in this document) some have special meanings to the Configuration Management engine. The same caution obviously applies to any word that might be used as a System or User-defined Group keyword.

As an added benefit to this double usage, the Configuration Management engine can be used to "search" for devices with certain words in their "Descriptions." When a word is entered into the Group Control String text box on the main Focal Point screen, the "EDIT" indicator will appear on the images (in the Cabinet View Screen) of the Devices with Device Group Strings that contain the keyword.

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