Blast Radius Simulator

Last Updated: January 6, 2026 Estimated Reading Time: 5 minutes

Overview

The Blast Radius Simulator shows the CIs that a failure or change can affect. Use it for change management, risk assessment, and incident planning.

How It Works

  1. Select the source CI - Choose the CI to simulate (for example, a database server).
  2. Set the simulation depth - Set how many relationship levels to traverse (1-10).
  3. Choose the direction - Choose upstream, downstream, or both.
  4. Run the simulation - The AI traverses the relationships and applies criticality weights.
  5. Review the results - See all the CIs and business services that the failure affects.

Configuration Options

Source CI

Select from dropdown or search:

  • Type CI name to filter
  • Shows CI class and environment
  • Only production CIs recommended for change assessment

Simulation Depth

Levels 1-10: How far to traverse relationships

| Depth | Use Case | |-------|----------| | 1-2 | Direct dependencies only | | 3-5 | Recommended for most cases | | 6-8 | Deep analysis, large blast radius | | 9-10 | Comprehensive (may be slow) |

Start with depth 3-5. Increase only if you need more comprehensive analysis.

Direction

Downstream (Default)

  • What depends on this CI?
  • "If this CI fails, what breaks?"
  • Most common for change impact

Upstream

  • What does this CI depend on?
  • "What could cause this CI to fail?"
  • Useful for incident analysis

Both

  • Complete impact picture
  • Takes longer to calculate
  • Most comprehensive

Results

Impact Summary

  • Total CIs impacted: Count of all CIs in blast radius
  • Critical services: Business-critical services at risk
  • High impact CIs: Count by criticality level
  • Risk score: 0-100 score based on criticality weighting

Impacted CIs List

Table showing all affected CIs:

  • CI name and class
  • Relationship path (how connected)
  • Criticality level (Critical/High/Medium/Low)
  • Business services impacted
  • Health score

Visualization

Graph view showing:

  • Source CI (highlighted)
  • All impacted CIs
  • Relationship paths
  • Color-coded by criticality

Business Services

List of business services in blast radius:

  • Service name
  • Number of CIs in path
  • Criticality level
  • Service owner

How to Use Simulations

For Change Management

Before CAB (Change Advisory Board):

  1. Run simulation on target CI
  2. Export results to PDF
  3. Attach to change request
  4. Present risk score to CAB

Questions to ask:

  • How many critical services impacted?
  • Can we schedule during maintenance window?
  • What is the rollback plan?

For Incident Response

During Major Incident:

  1. Identify failed CI
  2. Run upstream simulation
  3. Find root cause in dependency chain
  4. Run downstream to assess total impact

For Risk Assessment

Quarterly Risk Reviews:

  1. Simulate failure of critical infrastructure
  2. Document blast radius
  3. Plan mitigation strategies
  4. Update disaster recovery plans

Simulation History

View past simulations:

  • Date and time run
  • Source CI
  • Configuration used
  • Results summary
  • Rerun - Execute again with same config
  • Compare - Compare with current results

cmdbx saves each simulation automatically. Use the history to see how the blast radius changes as you improve your CMDB.

Weights and Criticality

cmdbx uses intelligent weights:

Relationship Weights

  • Contains (1.5x) - Strong dependency
  • Runs on (1.5x) - Infrastructure dependency
  • Depends on (1.25x) - Logical dependency
  • Connects to (1.0x) - Network connection
  • Managed by (0.5x) - Weak relationship

CI Criticality

  • Critical - Mission-critical systems (2.0x weight)
  • High - Important systems (1.5x weight)
  • Medium - Standard systems (1.0x weight)
  • Low - Non-essential systems (0.5x weight)

How to Export Results

Export to these formats:

  • PDF - Formatted report for change requests
  • CSV - Impacted CI list for analysis
  • PNG - Graph visualization for presentations

Include:

  • Simulation configuration
  • Impact summary
  • Full CI list
  • Business services affected
  • Recommendations

Best Practices

  • Run simulations before every major change

  • Start with depth 3-5 (not 10)

  • Export results for audit trail

  • Review business services impacted

  • Use in change request documentation

  • Compare before/after CMDB improvements

  • Do not simulate on dev/test CIs for prod changes

  • Do not ignore high-impact results

  • Do not run depth 10 on large CMDBs (slow)

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