leo-claude-mktplace/plugins/cmdb-assistant/commands/ip-conflicts.md

description

description
Detect IP address conflicts and overlapping prefixes in NetBox

CMDB IP Conflict Detection

Visual Output

When executing this command, display the plugin header:

┌──────────────────────────────────────────────────────────────────┐
│  🖥️ CMDB-ASSISTANT · IP Conflict Detection                       │
└──────────────────────────────────────────────────────────────────┘

Then proceed with the analysis.

Scan NetBox IPAM data to identify IP address conflicts and overlapping prefixes.

Usage

/ip-conflicts [scope]

Scopes:

• all (default) - Full scan of all IP data
• addresses - Check for duplicate IP addresses only
• prefixes - Check for overlapping prefixes only
• vrf <name> - Scan specific VRF only
• prefix <cidr> - Scan within specific prefix

Instructions

You are an IP conflict detection specialist that analyzes NetBox IPAM data for conflicts and issues.

Conflict Types to Detect

1. Duplicate IP Addresses

Multiple IP address records with the same address (within same VRF).

Detection:

1. Use ipam_list_ip_addresses to get all addresses
2. Group by address + VRF combination
3. Flag groups with more than one record

Exception: Anycast addresses may legitimately appear multiple times - check the role field for "anycast".

2. Overlapping Prefixes

Prefixes that contain the same address space (within same VRF).

Detection:

1. Use ipam_list_prefixes to get all prefixes
2. For each prefix pair in the same VRF, check if one contains the other
3. Legitimate hierarchies should have proper parent-child relationships

Legitimate Overlaps:

• Parent/child prefix hierarchy (e.g., 10.0.0.0/8 contains 10.0.1.0/24)
• Different VRFs (isolated routing tables)
• Marked as "container" status

3. IPs Outside Their Prefix

IP addresses that don't fall within any defined prefix.

Detection:

1. For each IP address, find the most specific prefix that contains it
2. Flag IPs with no matching prefix

4. Prefix Overlap Across VRFs (Informational)

Same prefix appearing in multiple VRFs - not necessarily a conflict, but worth noting.

MCP Tools

• ipam_list_ip_addresses - Get all IP addresses with filters:

  • address - Filter by specific address
  • vrf_id - Filter by VRF
  • parent - Filter by parent prefix
  • status - Filter by status

• ipam_list_prefixes - Get all prefixes with filters:

  • prefix - Filter by prefix CIDR
  • vrf_id - Filter by VRF
  • within - Find prefixes within a parent
  • contains - Find prefixes containing an address

• ipam_list_vrfs - List VRFs for context

• ipam_get_ip_address - Get detailed IP info including assigned device/interface

• ipam_get_prefix - Get detailed prefix info

Workflow

1. Data Collection

   • Fetch all IP addresses (or filtered set)
   • Fetch all prefixes (or filtered set)
   • Fetch VRFs for context

2. Duplicate Detection

   • Build address map: {address+vrf: [records]}
   • Filter for entries with >1 record

3. Overlap Detection

   • For each VRF, compare prefixes pairwise
   • Check using CIDR math: does prefix A contain prefix B or vice versa?
   • Ignore legitimate hierarchies (status=container)

4. Orphan IP Detection

   • For each IP, find containing prefix
   • Flag IPs with no prefix match

5. Generate Report

Report Format

## IP Conflict Detection Report

**Generated:** [timestamp]
**Scope:** [scope parameter]

### Summary

| Check | Status | Count |
|-------|--------|-------|
| Duplicate IPs | [PASS/FAIL] | X |
| Overlapping Prefixes | [PASS/FAIL] | Y |
| Orphan IPs | [PASS/FAIL] | Z |
| Total Issues | - | N |

### Critical Issues

#### Duplicate IP Addresses

| Address | VRF | Count | Assigned To |
|---------|-----|-------|-------------|
| 10.0.1.50/24 | Global | 2 | server-01 (eth0), server-02 (eth0) |
| 192.168.1.100/24 | Global | 2 | router-01 (gi0/1), switch-01 (vlan10) |

**Impact:** IP conflicts cause network connectivity issues. Devices will have intermittent connectivity.

**Resolution:**
- Determine which device should have the IP
- Update or remove the duplicate assignment
- Consider IP reservation to prevent future conflicts

#### Overlapping Prefixes

| Prefix 1 | Prefix 2 | VRF | Type |
|----------|----------|-----|------|
| 10.0.0.0/24 | 10.0.0.0/25 | Global | Unstructured overlap |
| 192.168.0.0/16 | 192.168.1.0/24 | Production | Missing container flag |

**Impact:** Overlapping prefixes can cause routing ambiguity and IP management confusion.

**Resolution:**
- For legitimate hierarchies: Mark parent prefix as status="container"
- For accidental overlaps: Consolidate or re-address one prefix

### Warnings

#### IPs Without Prefix

| Address | VRF | Assigned To | Nearest Prefix |
|---------|-----|-------------|----------------|
| 172.16.5.10/24 | Global | server-03 (eth0) | None found |

**Impact:** IPs without a prefix bypass IPAM allocation controls.

**Resolution:**
- Create appropriate prefix to contain the IP
- Or update IP to correct address within existing prefix

### Informational

#### Same Prefix in Multiple VRFs

| Prefix | VRFs | Purpose |
|--------|------|---------|
| 10.0.0.0/24 | Global, DMZ, Internal | [Check if intentional] |

### Statistics

| Metric | Value |
|--------|-------|
| Total IP Addresses | X |
| Total Prefixes | Y |
| Total VRFs | Z |
| Utilization (IPs/Prefix space) | W% |

### Remediation Commands

Remove duplicate IP (keep server-01's assignment)

ipam_delete_ip_address id=123

Mark prefix as container

ipam_update_prefix id=456 status=container

Create missing prefix for orphan IP

ipam_create_prefix prefix=172.16.5.0/24 status=active

CIDR Math Reference

For overlap detection, use these rules:

• Prefix A contains Prefix B if: A.network <= B.network AND A.broadcast >= B.broadcast
• Two prefixes overlap if: A.network <= B.broadcast AND B.network <= A.broadcast

Example:

• 10.0.0.0/8 contains 10.0.1.0/24 (legitimate hierarchy)
• 10.0.0.0/24 and 10.0.0.128/25 overlap (10.0.0.128/25 is within 10.0.0.0/24)

Severity Levels

Issue	Severity	Description
Duplicate IP (same interface type)	CRITICAL	Active conflict, causes outages
Duplicate IP (different roles)	HIGH	Potential conflict
Overlapping prefixes (same status)	HIGH	IPAM management issue
Overlapping prefixes (container ok)	LOW	May need status update
Orphan IP	MEDIUM	Bypasses IPAM controls

Examples

• /ip-conflicts - Full scan for all conflicts
• /ip-conflicts addresses - Check only for duplicate IPs
• /ip-conflicts prefixes - Check only for overlapping prefixes
• /ip-conflicts vrf Production - Scan only Production VRF
• /ip-conflicts prefix 10.0.0.0/8 - Scan within specific prefix range

User Request

$ARGUMENTS