IBM Proventia Network Enterprise User Manual - Stages of A Scanning Process
Stages of a Scanning Process
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IBM Proventia Network Enterprise Scanner User Guide, Version 1.3
Stages of a Scanning Process
Introduction
Many factors affect when and how scan jobs run. This topic ties these factors together in a
process that identifies the stages of a scanning cycle and explains the considerations at
each stage.
Dynamic
prioritization
Scanning jobs are prioritized at the task level so that a complete scan job does not have to
finish before another scan job with higher priority tasks can be processed. When an agent
completes a subtask, it processes the next subtask with the highest priority next.
Example:
A background scan may be running when you start an ad hoc scan. You do not
have to stop the background scan. The background scan continues until it has processed
its current subtask, then the ad hoc scan takes priority and starts to run.
The process for a
scanning cycle
Table 47 describes the general process for a scanning cycle:
Stage
Description
1
Scanning jobs appear in the Command Jobs window as they are scheduled:
•
A job for a background scan is scheduled at midnight on the first day of the refresh
cycle defined in the Scan Control policy for a group.
•
A job for an ad hoc scan is scheduled when you initiate the scan.
2
A job is ready to run follows:
•
For background scans or ad hoc scans that run in scan windows, the job runs as soon
as an open scan window is available.
•
For ad hoc scans that can run any time, the job runs as soon as possible after you
initiate it.
3
When a job is scheduled, the agent divides it into tasks:
•
The first task created for all scans is a management (parent) task that oversees the
scanning tasks.
•
For discovery scans, there is one additional scanning task.
•
For assessment scans, additional scanning tasks are created based on the priorities
described in “Priorities for Running Tasks” on page 129.
4
When an agent is available to run the scan, the agent finds the task with the highest
priority. The agent then runs a subtask of that task. The subtask is equal to the subtask
size determined by the maximum number of IP addresses or of assets defined for that
agent in the ESM policy.
5
The remaining subtasks run as follows:
•
If you have only one agent, the same agent takes the next subtask.
•
If you have more than one agent, the first available agent takes the next subtask.
6
Subtasks continue to run until you pause or cancel the scan, or until one of the following
occurs:
•
For ad hoc scans, until all the assets have been scanned.
•
For background scans, until all the assets have been scanned or until the scanning
cycle ends, whichever occurs first.
Table 47: The process of a scanning cycle