Monitor Data Center Block Rules and Tune the Rulebase

Monitor traffic that you explicitly block so that you can investigate potential attacks and evaluate whether you should allow any of the blocked traffic.
Developing a best practice security policy is an iterative process. As soon as you Create Data Center Traffic Block Rules, start monitoring traffic that matches the block rules designed to identify policy gaps, unexpected behaviors, and potential attacks. Tune your application whitelist rules to account for traffic that matches the block rules but should be allowed and investigate traffic that may indicate an attack.
Reports on blocked traffic contain valuable information you can use to investigate potential issues. Keep the block rules in the rulebase to protect your valuable data center assets and provide that information when traffic matches a block rule.
Follow content update best practices to keep your firewall protection up-to-date. Maintain the Data Center Best Practice Rulebase includes specific best practices for data center firewalls.
  1. Create custom reports to monitor traffic that matches the block rules designed to identify policy gaps and potential attacks.
    1. Select
      Monitor
      Manage Custom Reports
      .
    2. Add
      a report and give it a
      Name
      that describes the report’s purpose, in this example
      DC Best Practice Policy Tuning
      .
    3. Set the
      Database
      to
      Traffic Summary
      . (This also changes the default
      Selected Columns
      ; the default columns are
      Source Zone
      ,
      Destination Zone
      ,
      Sessions
      , and
      Bytes
      .)
    4. Select the
      Scheduled
      box.
    5. From
      Available Columns
      , add
      Application
      ,
      Risk of App
      ,
      Rule
      , and
      Threat
      to the
      Selected Columns
      list. If there are other types of information you want to monitor, select those as well.
    6. Set the desired
      Time Frame
      ,
      Sort By
      , and
      Group By
      values, in this example
      Last 7 Days
      ,
      Apps
      , and
      App Sub Category
      , respectively.
    7. Define the query to match traffic hitting the rules designed to find policy gaps and potential attacks. You can create a single report for traffic that matches any of the rules using the
      or
      operator, or create individual reports to monitor each rule. In the
      Query Builder
      , specify the name of each rule you want to include in the report. This example uses the names of the six blocking rules designed to find policy gaps and uses the
      Or
      operator to include information about traffic that matches any of the rules:
      • (rule eq ‘Known user nonstandard ports’)
      • (rule eq ‘Unknown user nonstandard ports’)
      • (rule eq ‘Unexpected App from user Zone’)
      • (rule eq ‘Unexpected App from any Zone’)
      • (rule eq ‘Unexpected User App Any Port’)
      • (rule eq ‘Unexpected App Any Port’)
      custom-report-dc-bp-policy-tuning.png
  2. Review the report (or reports) regularly to make sure you understand why traffic matches each block rule and either update policy to include legitimate applications and users, or use the information to assess the risk of traffic that matches the rules.

Related Documentation