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Discovery IP address configuration

Discovery IP address configuration

Use one or more of these methods in any combination to define the network or network segment for Discovery to query.

Note: If you do not know the IP addresses in the network, run Network Discovery first to determine the IP networks. Then, convert the IP networks into IP address range sets.

IP address list

Use IP address lists to add individual addresses for Discovery to query. These addresses should not be included in any existing IP range or IP network. You can enter the IP address of the device or a host name (DNS name). If you enter a host name, it must be resolvable from the MID Server system.

IP address range

You can define arbitrary ranges of IP addresses for Discovery to query. This is a good way to include selected segments of a network or subnet. However, Discovery has no way of knowing if the IP range includes addresses for private networks or broadcast addresses and scans all the addresses in the range. If the network and broadcast addresses are included, then the results are inaccurate. For this reason, discoveries configured to detect IP networks are generally more accurate than those configured for IP address ranges. Include only those IP addresses in your range that are reserved for manageable devices on the public network.

IP network

An IP network includes the range of available IP addresses in that network, including the network address (the lowest address in the range) and the broadcast address (the highest address in the range). An example of a class C network range is 192.168.0.0 to 192.168.0.255. In the Range Set form, this network can be entered with either of the following notations:
  • 192.168.0.0/24
  • 192.168.0.1/255.255.255.0

This notation indicates that Discovery is scanning an IP network, and Discovery does not scan the highest and lowest numbers in the range. This prevents significant errors from being introduced into the Discovery data by the broadcast address, which returns all the devices in the network, and the network address, which can add an arbitrary number of redundant devices. This built-in control makes IP networks the best method of defining which IP address ranges to query.

IP address selection properties

You can use system properties to control the selection of IP address for specified CI classes.

Use these properties to determine if the system should replace the IP address returned by Discovery in a device's CI record if the address does not match that of a network interface (NIC) on the device. This is important for the discovery of devices with management IP addresses that differ from IP addresses associated with one or more NICs on the device. Because a device's management IP is used in the Discovery schedule for that device, this is the address that Discovery returns. Use these properties to determine which IP address to use for CIs of any class.

Property Description
glide.discovery.enforce_ip_sync Prevents the system from using a discovered IP address in the CI record if the address doesn't match that of a NIC on the device. If this property is true, Discovery checks the IP address returned to determine if it is associated with a NIC on the device. If the address is not associated with a NIC, Discovery uses the IP address from one of the NICs instead.
  • Type: true | false
  • Default value: true
glide.discovery.exclude_ip_sync_classes Defines CI classes whose IP addresses should not be substituted if the address returned by Discovery does not match one of the devices' NICs. Use a comma separated list to define multiple classes. By default, the system uses the management IP of a load balancer returned by Discovery in the CI record, rather than substituting it for the IP address of one of the load balancer's NICs.
  • Type: string
  • Default value: cmdb_ci_lb

Create a Quick IP range for a Discovery schedule

Quick ranges allow administrators to define IP addresses to scan in a single comma-delimited string without creating separate records.

Before you begin

Only MID Servers that are up and validated are used with quick ranges. The MID Servers must specify the Discovery application (or ALL applications) and have IP ranges configured if you use the auto-select feature on the Discovery schedule.

About this task

You can enter IP addresses in one of the following formats:
  • An IP range defined by a slash and the number of bits in the subnetwork. For example, the string 10.10.10.0/24 scans 24 bits of IP addresses from 10.10.10.0 to 10.10.10.254.
  • An IP range defined by a dash. For example, the string 10.10.11.0-10.10.11.165 scans the IP addresses from 10.10.11.0 to 10.10.11.165.
  • A comma-separated list of specific IP addresses. For example the string 10.10.11.200,10.10.11.235 scans the IP addresses 10.10.11.200 and 10.10.11.235.

Procedure

  1. Click the Quick Ranges related link on the Discovery Schedule form.
  2. Enter the IP ranges and specific IP addresses to scan.
  3. Click Make Ranges.
    Note: The Quick Range interface is for entering IP addresses only and cannot be used to edit IP addresses that have already been submitted.
    Figure 1. Discovery Quick Ranges
    The instance automatically displays the entries in the proper format.
  4. To make any changes to IP address ranges, select the IP address records.
    Figure 2. Discovery IP Ranges

Import IP ranges into Discovery schedules with import sets

The most efficient method of entering large numbers of IP networks into Discovery schedules is through the use of import sets.

About this task

Common groups of IP addresses, known as ranges can be used in Advanced Discovery schedules.

Use a data source that can be mapped, such as an Excel spreadsheet (network.xls in the following example).
Figure 3. Sample XLS file
Sample XLS file

Procedure

  1. Navigate to System Import Sets > Load Data.
  2. Identify the file or data source that contains the desired information.
  3. Create a new table name, such as ipnetworks.
  4. Select Upload an Excel file and browse to the source file.
  5. Click Go to import the file.
    Figure 4. Data Source
  6. Navigate to System Import Sets > Create Transform Map and map the items in the Excel spreadsheet to the fields of the CMDB in the target table Discovery IP Range [discovery_range_item] table.
  7. Give the Transform Map a unique and descriptive name.
    Figure 5. Table Transform Map 1
  8. Submit the form, and then click New in the Field Maps Related List.
  9. Map the fields from the Excel spreadsheet to the fields in the Discovery IP Range (discovery_range_item) table using the following field names:
    • RangeName to Discovery Range
    • IP to Network IP
    • mask to Network Mask (or Bits)
    • type to Type. Note that the type field is case sensitive.
    The display names are different from the actual field names that appear in the Field Maps list.
    Figure 6. Table Transform Map 2
  10. Click the Mapping Assist Related Link and use the lists that appear to resolve the fields between the table and the data source (the Excel spreadsheet in this example).
    Figure 7. Mapping Assist

    This produces the complete map between the data source and the fields to populate in the CMDB.

  11. Click Save.

    The view returns to the Table Transform Map form.

  12. Click Transform in the Related Links to move the data into the proper fields in the Discovery IP Range (discovery_range_item) table.

    The imported IP ranges are available now for use in any advanced Discovery schedule.

Exclude IP addresses

Administrators can exclude specific IP addresses in a range or network from a Discovery Schedule.

About this task

For example, you might exclude a subnet containing devices restricted from interacting with other devices or exclude a device with an intentionally unorthodox configuration that causes an authentication issue each time it is discovered.

To exclude an IP address:

Procedure

  1. In the Discovery Schedule form, click the link for the Type of IP address range that contains the address to exclude.

    For example, to exclude 10.10.10.28, select the IP Network for 10.10.10.0/24, which is the range of IP addresses that contains the target address.

    Figure 8. Exclude IP Address
    The Discovery IP Range form appears.
    Figure 9. Exclude IP Address 1
  2. In the Discovery Range Item Excludes related list, click New.
  3. In the Discovery Range Item Exclude form, select a Type for the excluded IPs. For example, select IP Address List to exclude a single IP address or multiple IP addresses that are not sequential.
  4. Right-click the header bar and select Save from the context menu.
    The Discovery Range Item IPs related list appears.
    Figure 10. Exclude IP Address 2
  5. Click New in this list.

    An entry form for the IP addresses to exclude appears.

  6. Enter the IP address to exclude, and then click Submit.
    Figure 11. Exclude IP Address 3
    The excluded IP address appears in the Discovery Range Item IPs related list for that IP address Type.
    Figure 12. Exclude IP Address 4
  7. Click Update to save the excluded address and return to the Discovery Schedule.