Capacity Planning

Purpose: Automate network capacity planning tasks and prioritize actions using growth forecasts and projected run-out dates.
Benefits: - Automate data gathering and correlation to prioritize the most critical capacity issues.
- Eliminate complex spreadsheets and manual planning processes.
- Prevent congestion surprises that impact applications or users.
Use Cases: Capacity Planning
Relevant Roles: Network Architect, Procurement Team

Capacity Planning is covered in the following topics:

 

About Capacity Planning

Capacity Planning, and Kentik’s approach to it, are covered in the following topics:

 
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Capacity Planning Overview

Capacity planning for a network involves figuring out when interfaces are approaching the limits of their capacity. In many cases, capacity planning has traditionally been a completely manual process with complex spreadsheets to pull in the data, aggregate it, run statistics on it, and trend it over time.

In Kentik, the Capacity Planning workflow (Core » Capacity) enables you to quickly assess the utilization of links relative to link capacity so that you can take action before links become overloaded. You’ll see not only current traffic volume, but also utilization trends and how soon your links are likely to reach capacity. And you can assign interfaces to multiple groups and evaluate utilization independently for each group according to custom criteria. These capabilities enable service providers and other network operators to optimize the use of their infrastructure, delivering the best possible service while avoiding overspend on capacity.

 
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Capacity Planning Use Cases

The following table lists some use cases of Capacity Planning for various roles within a network organization.

Role Scenarios
Network Architect - Determine when to purchase or design upgraded bandwidth.
- View capacity to individual network providers to determine when to make network upgrades or decommission underutilized capacity for a given provider.
- View capacity to groups of customer interfaces to determine when to recommend network upgrades to a given customer.
Procurement Team - View capacity to individual network providers to determine when to make network upgrades or decommission underutilized capacity for a given provider.

 

Capacity Planning Page

The Capacity Planning page provides high-level information about the capacity plans in your organization and serves as the access point to the pages for each of your individual capacity plans. The Capacity Planning page is covered in the following topics:

 
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Capacity Planning Page UI

The main elements of the Capacity Planning page include the following:

  • Add Capacity Plan: A button that opens the configuration page for a new capacity plan (see Configure Capacity Plan).
  • Capacity Plan List: A set of cards listing all of your organization’s existing capacity plans (see Capacity Plan List).
 
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Capacity Plan List

Your organization’s existing capacity plans are listed as a set of cards that each contain the following UI elements:

  • Utilization status: Indicates how the traffic volume on the interfaces of this plan’s capacity group compares to the Warning and Critical thresholds set with the Utilization setting on this plan’s configuration page (see Capacity Plan Thresholds). Plan utilization status may be Normal, Warning, or Critical.
  • Runout status: Indicates how the calculated runout duration for the interfaces of this plan’s capacity group compares to the Warning and Critical thresholds set with the Runout setting on this plan’s configuration page. Plan runout status may be Normal, Warning, or Critical.
  • Plan name: Your organization’s name for this capacity plan. Click on the name to open this plan’s Capacity Plan Page.
  • Plan description: A description of the capacity plan.
  • Critical interfaces: A count of the interfaces in this plan’s capacity group whose status is Critical.
  • Warning interfaces: A count of the interfaces in this plan’s capacity group whose status is Warning.
 

Capacity Plan Page

The main elements of the Capacity Plan page are covered in the following topics:

 
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Capacity Plan Title Bar

The title bar of the Capacity Plan page includes the following UI elements:

  • Plan name: The name of this capacity plan.
  • Description: A description of this capacity plan.
  • Edit Plan button: Opens the Configure Capacity Plan page.
  • Delete Plan button: Opens a confirming popup that enables you to remove the plan from your organization’s collection of plans.
 
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Capacity Plan Indicators

The Capacity Plan page includes the following indicators (below the title bar).

  • Runout Calculation: The current Runout Calculation Strategy setting from the Thresholds pane on this plan’s configuration page (see Capacity Plan Thresholds).
  • Utilization Aggregate: The current Utilization Aggregate setting from the Thresholds pane on this plan’s configuration page.
  • Total Interfaces: A count of the interfaces in this capacity plan’s capacity group.
  • Critical: A count of the interfaces in this capacity plan’s capacity group whose current status is Critical as defined by either the Capacity or Runout threshold (see Capacity Plan Thresholds).
  • Warning: A count of the interfaces in this capacity plan’s capacity group whose current status is Warning as defined by either the Capacity or Runout threshold.
 
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Capacity Group Listing

The main UI elements in this part of the page are as follows:

  • Filter field: Enter text to narrow the Group Interfaces list to rows in which the first column contains the entered text.
  • Group interfaces list: A table listing the interfaces in this capacity plan’s capacity group (see Group Interfaces List).

Group Interfaces List

This table lists the interfaces currently assigned to this capacity plan’s capacity group (see Configure Capacity Group). The table contains the following columns:

  • Interface: This column contains the following information for each interface:
    - Interface description: Either as defined in the device and retrieved via SNMP or as entered manually when adding the interface.
    - Connectivity Type: See Understanding Connectivity Types.
    - Capacity: Capacity in Mbps for the interface either as retrieved via SNMP or as entered manually when adding the interface.
  • Utilization: Provides information about the volume of traffic on the interface, calculated over the period specified with the current Runout Calculation Strategy (last month or last week) and using the current Utilization Aggregate (see Capacity Plan Thresholds). The following information is provided, broken into inbound (In) and outbound (Out):
    - Percentage: The actual volume as a percent of the interface capacity.
    - Mbps: The actual volume in Mbps.
  • Runout/Trend: Broken into inbound (In) and outbound (Out):
    - Runout date: The projected runout of capacity on the interface. If the projected runout date is more than a year in the future the displayed value is “Over a year.” If it’s too far out to be calculated (e.g. the utilization trend is declining) the value is stated as “N/A.” If capacity has already been exceeded, the displayed value is “Over Capacity.”
    - Utilization Trend: The trend in actual traffic over the most recent period (week or month depending on this capacity plan’s Runout Calculation Strategy setting).
 

Configure Capacity Plan

The configuration of capacity plans is covered in the following topics:

 
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Configure Capacity Plan UI

The configuration page for a capacity plan includes the following fields and controls:

  • Name: The name of the capacity plan.
  • Description: A description of the capacity plan.
  • Thresholds: Settings for the thresholds used to define the current status (Normal, Warning, Critical) of the plan (see Capacity Plan Thresholds).
  • Interfaces pane: Display of, and controls for, the dynamic groups and individual interfaces in this capacity plan’s capacity group (see Capacity Plan Interfaces).
  • Cancel: Exit the page without saving the changes made to the settings.
  • Save: Save the current settings and exit the page.
 
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Capacity Plan Thresholds

Each capacity plan includes threshold settings for the following:

  • Utilization: Interface traffic volume relative to capacity, as reported by SNMP or Streaming Telemetry.
    Note: Streaming Telemetry is not currently implemented for capacity planning.
  • Runout: The number of months before traffic will exceed capacity if present trends continue.

The settings for these thresholds let you define the conditions under which the status of a given interface becomes Warning or Critical. The following controls are provided for these settings:

  • Utilization: A dual-slider control that sets the following:
    - Warning threshold (left slider): The percent of capacity above which traffic volume will trigger the Warning state.
    - Critical threshold (right slider): The percent of capacity above which traffic volume will trigger the Critical state.
  • Utilization Aggregate: The aggregation method (average, maximum, 95th percentile, 98th percentile) used to measure traffic volume.
  • Runout: A dual-slider control that sets the following:
    - Warning threshold (left slider): The number of months below which the runout will trigger a Warning state.
    - Critical threshold (right slider): The number of months below which the runout will trigger a Critical state.
  • Runout Calculation Strategy: The comparison period used when calculating, based on the current Utilization Aggregate method, the runout (assuming that current trends continue):
    - Week over Week (WoW): Compare the most recent week (back in time from the present) with the week before that.
    - Month over Month (MoM): Compare the most recent month (back in time from the present) with the month before that.
 
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Capacity Plan Interfaces

The Interfaces pane of a Configure Plan page includes the following elements:

  • Configure Capacity Group: A button that opens the Configure Capacity Group dialog, where you can specify the interfaces and dynamic groups in the capacity group.
  • Dynamic Groups: A list of dynamic groups, each of which represents a set of criteria that were specified in the Configure Capacity Group dialog (see Capacity Group Lists). The row for each group in the list indicates that group's filter criteria and the current count of its interfaces.
    Note: These groups are dynamic because all interfaces on your network that currently meet the criteria for a listed dynamic group will be included in the capacity group even if those interfaces didn't exist or didn't meet the criteria when the dynamic group was created.
  • Selected Interfaces: A list of interfaces that have been individually selected from the Matching Interfaces List (in the Configure Capacity Group dialog) for inclusion in this capacity plan’s capacity group. In each row, the top line is the interface’s SNMP alias and the bottom line is the interface’s description (see Information SNMP OIDs).
 

Configure Capacity Group

The Configure Capacity Group dialog, which opens from the Select Interfaces button on the Configure Capacity Plan page, is used to build, either directly or via dynamic filtering, a list of the interfaces in a capacity plan’s capacity group. The dialog is covered in the following topics:

 
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Configure Capacity Group UI

The Configure Capacity Group dialog includes the following main UI elements:

  • Filters: Filters used to narrow the set of interfaces that you might wish to include in a capacity plan’s capacity group (see Filters Pane).
  • Group By: A set of buttons that determine how the interfaces in the Matching Interfaces list will be organized into groups, either by Device, Connectivity Type, or Network Boundary (see Interface Classification Dimensions).
  • Create Dynamic Group: A button, active only when one or more filters are set in the filters pane, that creates a dynamic group made up of all interfaces that match the current filter criteria.
    Note: The composition of a dynamic group will change in response to changes in the interfaces that match the group's filter conditions. For example, if a group is defined as interfaces on a given device whose network boundary is external, then additional external interfaces added on that device will become members of that group.
  • Matching Interfaces: A list of the individual interfaces available to add to the Selected Interfaces list at the right of the dialog. By default the Matching Interfaces List will include the interfaces on all of your Kentik-registered devices. To make it easier to see the interfaces that you want to select, or to define dynamic groups of interfaces, you can use the Filters pane at the left of the dialog.
  • Dynamic Groups: A list of the dynamic groups that are part of this Capacity Group (see Capacity Group Lists).
  • Selected Interfaces: A list of the individual interfaces that you've added to this Capacity Group (see Capacity Group Lists).
  • Cancel: Exit the dialog, leaving the capacity group as it was when the dialog was opened.
  • Save: Exit the dialog, updating the capacity group to the current dynamic groups and selected interfaces.
 
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Filters Pane

The Filters pane includes the following filter controls (fields and checkboxes):

  • Name: Match interfaces whose name contains the entered string.
  • Description: Match interfaces whose description contains the entered text (case insensitive).
  • IP: Match interfaces with the entered IP/CIDR address range.
  • Device: Match interfaces whose device name contains the entered string.
  • Capacity: Match interfaces whose capacity matches the entered value.
  • Logical Interfaces Only: Show only interfaces that have been assigned an IP address.
  • Provider: Match interfaces whose source/destination traffic reaches the Internet via the entered provider.
  • Connectivity Type: Match interfaces whose Connectivity Type is checked (see Understanding Connectivity Types).
  • Network Boundary: Match interfaces whose Network Boundary is checked (see Network Boundary Attribute).

You can use the above filter controls to narrow the set of available interfaces. The Matching Interfaces List will update to show only interfaces that match the current filters, and the Create Dynamic Group button will become active.

 
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Matching Interfaces List

The Matching Interfaces list is populated based on the current filters in Filters Pane and grouped according to the Group By buttons. Interfaces in the list can be manually designated for inclusion in the Selected Interfaces list by clicking on the + icon at the right of each row.

The list includes the following columns and controls:

  • Interface: In each row, the top line is the interface’s SNMP alias and the bottom line is the interface’s description (see Information SNMP OIDs).
  • Information: Indicators showing the interface’s capacity, connectivity type, and network boundary (see Interface Classification Dimensions).
  • Add (+): An icon at the right of an individual row in the Matching Interfaces list. Click to add the corresponding interface to the Excluded Interfaces list.
 
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Capacity Group Lists

The Capacity Group lists show the two categories of interfaces that will make up the capacity group for the current capacity plan when the Configure Capacity Group dialog is closed with the Save button:

  • Dynamic Groups: Each listed item represents the set of criteria that was specified in the Filters Pane when the Create Dynamic Group button was clicked (one dynamic group per click of the button). The group is dynamic because all interfaces on your network that currently meet the criteria for a listed dynamic group will be included in the capacity group even if those interfaces didn't exist or didn't meet the criteria when the dynamic group was created.
  • Selected Interfaces: Each listed item represents, by SNMP alias, an interface added to the capacity group using the + icons in the Matching Interfaces List.

An item in either of the above lists may be manually removed from the group using the red X at the right of each row.

 

Using Capacity Planning

Using capacity planning involves setting up one or more capacity plans, including capacity groups (collections of interfaces), that you can monitor from the Capacity Plan page. The basic steps include:

  1. From the main menu, navigate to the Capacity Planning Page (Core » Capacity Planning).
  2. If your organization has no existing capacity plans, click the Add Capacity Plan button at upper right.
  3. On the Configure Capacity Plan page, enter a name and description for the plan.
  4. In the Thresholds pane (see Capacity Plan Thresholds):
    - Use the Utilization control to set the percent of capacity above which traffic volume will trigger the Warning state (left slider) and Critical state (right slider).
    - Use the Runout control to set the number of months below which the runout will trigger a Warning state (left slider) and Critical state (right slider).
    - Set the methods by which traffic will be aggregated (Utilization Aggregate) and compared (Runout Calculation Strategy) when it is evaluated for utilization and runout status.
  5. In the Interfaces pane, click the Configure Capacity Group button.
  6. In the resulting Configure Capacity Group dialog, the Matching Interfaces List will show all of the interfaces (on Kentik-registered devices) in your network.
  7. Use the fields of the Filters Pane to narrow the Matching Interfaces list.
  8. Do one of the following to define the capacity group for this capacity plan::
    - Add a dynamic group, based on current Filter pane settings, to the Dynamic Groups list (see Capacity Group Lists) by clicking the Create Dynamic Group button.
    - Add interfaces from the Matching Interfaces list to the Selected Interfaces list.
  9. Repeat step 8 until the Capacity Group Lists represent all of the interfaces (either directly or as dynamic groups) that you want in this capacity group, then click the Save button to close the dialog.
  10. The Interfaces list on the Configure Capacity Plan page will now list both the dynamic groups and the individual interfaces that you selected in the dialog.
  11. Click the Save Capacity Plan button to save your new plan. You’ll be returned to the Capacity Planning page, where you can see your new plan, including Utilization and Runout status, at the bottom of the Capacity Plan list.
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