Line Availability

Overview

This charts three types of availability events. Hover on the chart to see timestamp and additional details:

Impacting: typically outages, these have a duration and impact availability

Exclusions: events removed through planned maintenance or manual exclusion with SLA Now

Non-impacting: events which do not impact availability

The Line Availability section provides additional detail about the coloured blips on the Availability lines. The Event list can also be used to exclude specific events from Highlight's availability calculations. This is useful if a maintenance period occurred but was not scheduled in advance or if an incident happened which was not the fault of the service provider. Highlight will show Operational and Adjusted availability figures in the Summary and the SLA Compliance report.

Download option

Download the information to a CSV file to see all events for the selected time period (day, week or month) and any comments on events. The list is not affected by any Event list filter or by zooming in on the chart.

In the CSV download, events which have been excluded show:

Type: Excluded

Impacting: no

Impacting Duration: 00:00

Comment: as entered by the user who excluded or included the event

Options

The options below are all checked by default, uncheck to remove the events on each line from the chart. This also removes them from the Event list. Read more about each event type in the Availability event details section below.

Impacting (3)

The number in brackets after each event type indicates how many of that event have occurred in the selected time period (day, week or month). In the image, there were a total of 3 impacting events comprised of 1 brief outage and 2 down events. The numbers in brackets cover the entire time period and do not change if unchecked or when the chart is zoomed in.

Indeterminate: A line in any top checkbox indicates a mix of checked and unchecked sub-checkboxes

Event list: Unchecked by default, check to see more details for each event during the selected time period - read more about the event list in the section below

Saved settings

The settings below will be remembered when you next log in:

• Whether the panel is collapsed or expanded

• The status of all checkboxes

Colour coding

When viewed for today only, each section on the Details page gives an indication if it is currently alerting and thus impacting the associated heat tile colour. Find out more about colour coding.

Line Availability description

Download button: Download all events for the selected time period to a CSV file - see separate section above

Horizontal axis: Adjusts according to the selected time period to show "hours" in day view and "days" in week and month views; redraws if the time zone is changed at the top right of the Details page. See Zoom options for methods to zoom in on the data.

Time period

Highlight displays events in the time period. For week and month, the first event in the time segment is shown. Full details are shown on the day view:

Summary

For each event type, total duration for the time period (day, week or month) selected are shown. These are not affected by any Event list filter or by zooming in on the chart.

• Total event durations by type: a cumulative duration of all events in the selected time period split into:

  • Impacting

  • Exclusions

  • Non-impacting

• Operational availability:

  the percentage of time this watch was available in the time period; this will not include time before the device was activated nor outages during maintenance.

• Adjusted availability:

  the availability figure which is calculated using non-excluded impacting events. If no events are manually excluded, operational and impacting availability figures match. Refer to the Event list: Exclude events from availability calculations section below for details on how to exclude impacting events.

Operational and adjusted availability correspond to the figures shown in the SLA Compliance report for the same period.

Event list: General

Event list: Unchecked by default, check to see more details for each event during the selected time period

This list provides additional detail about the coloured blips (known as events). For the selected time period (day, week or month) each event shows its type, the time and date it occurred, the event details, duration and if it is impacting the availability figure or not.

The header shows Showing X of Y events where Y is the total number of events for the time period including events in maintenance. X is a reduced number if filters are applied.

Download the information to a CSV file to see all events and any comments - read more about the Download option in the section above

Sort

By default, events are sorted by date and time with the most recent event at the top. This can be reversed or you can sort by any of the column headers:

Type: Events are: impacting, excluded, maintenance or non-impacting

Time|Date** Sort by event start time [default]

Event Details: An alphabetical sort of events

Comment: An alphabetical sort of comments (only relevant on excluded events)

Duration: Show longest duration events first or last

Impacting: Sort by impacting or non-impacting

Search

Use the Search events field to show specific Event Details and comments. If an incident number is reliably included with a comment, you can search for it.

Event list: Exclude events from availability calculations

Users with the permission to Manage maintenance have two ways to exclude an outage from Highlight's availability calculations:

1. Before the event - set up a maintenance window

Refer to the Help & Support Centre for details on creating containers and putting them into maintenance

Purple background areas on the chart show current and past maintenance periods. Watches in maintenance do not send alerts nor change the colour of heat tiles.

2. After the event - exclude an outage

Notice the following in the above GIF:

1. Only events on the impacting line can be excluded

2. You can select more than one event at a time

3. A comment is required to enable the button

After exclusion:

1. The red impacting icon in the Event list turns to a grey exclusion icon

2. The comment is added to all events excluded at the same time

3. The impacting icon changes from impacting to non-impacting

4. On the chart, the excluded events move from the impacting line to the exclusions line

5. In the Summary, the Adjusted availability figure increases whilst the Operational availability figure is unchanged

Events can only be excluded if the parent folder has SLA Now enabled on the Features tab and the user has Manage maintenance permission

Check one or more impacting events then add a comment and select this buttonTo reverse exclusions, check those events which have previous been excluded (indicated with ), add a replacing comment and select this button

A comment is required each excluded event. We recommend including an incident number in the comment. This can then be searched for using the text filter in the dialog, in the CSV download or in the Audit log.

Event exclusions are recorded in the Audit Log against the watch with details of which user made the change, any comment and when.

Events which have been excluded have the following characteristics:

• the non-impacting indicator

• Duration: the duration of the event will be faded AND EITHER

• the maintenance icon which shows "Event occurred whilst watch in maintenance" on hover OR

• the grey excluded icon with the indicator with comment in the Comment column

In the CSV download, events which have been excluded show:

Type: Excluded

Impacting: no

Impacting Duration: 00:00

Comment: as entered by the user who excluded or included the event

The number of exclusions made and adjusted availability show in the SLA Compliance report with a red background if the availability figure is less than the SLA target.

Availability event details

Affects the Stability metric

The impacting line shows how available your connection has been. Availability is worked out as a percentage of the day, week or month that the watch was monitored. Several issues will cause outages which are shown as coloured blips on this line and decrease the availability percentage.

Show the event list for a full list of issues and outages, with exact timestamp and duration

Note: Ongoing and not contactable blips can be custom configured to be included in Total outages or not. This is set by the service provider at a folder level and inherited by subfolders unless overridden. If excluded from total outages, then the duration is shown in grey text to indicate it is excluded from the total outages figure and does not affect Operational availability.

The entries you may see are summarised in this table with full details below:

1. Amber: Brief outage

Overview

Shown as an amber blip, these are brief outages which indicate the link being monitored went down and came up again very briefly between the times Highlight polled it. Highlight can tell this has happened because the device timestamps the last interface change, so if the state changed between consecutive successful polls there must have been a brief outage.

For example, if this link state timestamp had increased between the check at 00:00 and the check at 00:03, we know the line was briefly down between those times, even though it looked healthy both times we checked it.

Cause

For a brief outage blip to be drawn, the line must be down for less than the polling period. The outage may have lasted for a few seconds, a minute or more. When the line comes back up, it will take a short time for routing to settle down, the router to start passing packets again, then for any connections using it to timeout and retry, so the effective outage will be longer. Highlight counts each transient outage as one minute of downtime, which is a sensible estimate.

2. Red: Down

This is where we regain contact with the device after an outage and establish that the monitored link definitely went down. The mustard (ongoing) blips will turn red. Like other red issues, this counts as a formal outage on your watch, shown by a red blip and the comment 'Circuit reported as down.' The availability percentage for that watch will be decreased.

A red line also occurs if a period of non-contact ends in a device restart.

3. Maroon: Out of service

If the monitored link has been shut down deliberately on the device, the event is 'out of service.'

4. Turquoise: Configuration changed

This indicates a change in the configuration of the monitored device itself and is shown as a turquoise blip.

5. Black: Device restarted

This is where the monitored device has been powered off/on or restarted and is shown by a black blip. If the link itself was down before the device was restarted you will see red blips with the last blip being black. For more details see point 6 below (Red: Circuit reported as down).

6. Mint: Unknown

If the event type cannot be determined, the type is 'Unknown' (event type)

7. Blue: Not contactable

If the last change timestamp for the monitored interface hasn't changed when connection is re-established after connectivity problems, Highlight knows that the line has been up all the time and we simply lost contact because of a problem elsewhere on the network. Highlight marks these events by turning mustard blips to blue with the comment 'No data : Device not contactable.' There was no outage detected by the device, although it was not reachable from the Highlight platform. The availability percentage is not decreased unless the folder option to treat blue as an outage is set to Yes.

A blue blip will also be shown if Highlight was previously set to monitor an unknown interface; or if the device does not support the "last change" parameter, unless the period of non-contact ends in a device restart which would cause the mustard blips to turn red.

8. Mustard: Ongoing

When Highlight loses contact with the device it is monitoring, we treat the outage as an ongoing connectivity issue shown by a mustard blip. Only once Highlight reconnects with the device we check the last change timestamp for the monitored interface, which determines if:

• the link went down whilst we were out of touch with it (the mustard colour changes to red 'down'); or

• the link did not go down (the mustard colour changes to blue 'not contactable') - see next point 3; or

• the period of non-contact ends in a device restart (the mustard colour changes to red 'down')

A mustard blip will also be shown if Highlight is set to monitor an unknown interface.

Zoom options

There are two methods to zoom in on charts: drag and click. Find out more about zoom options.

​Background colours

Grey backgrounds indicate non-business hours and purple backgrounds indicate maintenance periods. Find out more about background colours.