Managing Device42

Device42 IT Infrastructure Management Skill

Manage and analyze Device42 DCIM, dependency mapping, IP management, and assets.

API Conventions

Authentication

All API calls use Basic Auth (username:password) — injected automatically.

Base URL

https://{{instance}}/api/1.0

Core Helper Function

#!/bin/bash

d42_api() {
    local method="$1"
    local endpoint="$2"
    local data="${3:-}"

    if [ -n "$data" ]; then
        curl -s -X "$method" \
            -u "$DEVICE42_USER:$DEVICE42_PASS" \
            -H "Content-Type: application/json" \
            "${DEVICE42_URL}/api/1.0${endpoint}" \
            -d "$data"
    else
        curl -s -X "$method" \
            -u "$DEVICE42_USER:$DEVICE42_PASS" \
            -H "Content-Type: application/json" \
            "${DEVICE42_URL}/api/1.0${endpoint}"
    fi
}

Common Operations

Data Center & Rack Management

#!/bin/bash
echo "=== Data Centers ==="
d42_api GET "/buildings/" \
    | jq -r '.buildings[] | "\(.building_id)\t\(.name)\t\(.address // "-")"' \
    | column -t

echo ""
echo "=== Racks ==="
d42_api GET "/racks/?limit=25" \
    | jq -r '.racks[] | "\(.rack_id)\t\(.name)\t\(.building)\t\(.row)\tU:\(.size)"' \
    | column -t

echo ""
echo "=== Rack Utilization ==="
d42_api GET "/racks/?limit=50" \
    | jq -r '.racks[] | "\(.name)\tTotal U: \(.size)\tUsed U: \(.u_used // 0)\tFree: \((.size // 0) - (.u_used // 0))"' \
    | column -t | head -20

Application Dependency Mapping

#!/bin/bash
echo "=== Application Components ==="
d42_api GET "/appcomps/?limit=25" \
    | jq -r '.appcomps[] | "\(.appcomp_id)\t\(.name)\t\(.device_count // 0) devices"' \
    | column -t

echo ""
echo "=== Dependencies for Application ==="
APP_ID="${1:?App component ID required}"
d42_api GET "/appcomps/${APP_ID}/" \
    | jq -r '.depends_on[] | "\(.name)\t\(.type)"' | head -20

IP Address Management

#!/bin/bash
echo "=== Subnets ==="
d42_api GET "/subnets/?limit=25" \
    | jq -r '.subnets[] | "\(.subnet_id)\t\(.network)/\(.mask_bits)\t\(.name // "-")\tUsed: \(.used_count // 0)/\(.total_count // 0)"' \
    | column -t

echo ""
echo "=== Available IPs in Subnet ==="
SUBNET_ID="${1:?Subnet ID required}"
d42_api GET "/ips/?subnet_id=${SUBNET_ID}&available=yes&limit=15" \
    | jq -r '.ips[] | "\(.ip)\t\(.label // "-")\t\(.available)"' \
    | column -t

Device Management

#!/bin/bash
echo "=== Devices Summary ==="
d42_api GET "/devices/?limit=25&sort=last_updated&order=desc" \
    | jq -r '.Devices[] | "\(.device_id)\t\(.name)\t\(.type // "-")\t\(.os_name // "-")\t\(.last_updated[0:10])"' \
    | column -t

echo ""
echo "=== Devices by Type ==="
d42_api GET "/devices/?limit=500" \
    | jq -r '[.Devices[].type] | group_by(.) | map({type: (.[0] // "unknown"), count: length}) | sort_by(.count) | reverse | .[] | "\(.type): \(.count)"'

Output Format

Present results as a structured report:

Managing Device42 Report
════════════════════════
Resources discovered: [count]

Resource       Status    Key Metric    Issues
──────────────────────────────────────────────
[name]         [ok/warn] [value]       [findings]

Summary: [total] resources | [ok] healthy | [warn] warnings | [crit] critical
Action Items: [list of prioritized findings]

Target ≤50 lines of output. Use tables for multi-resource comparisons.

Anti-Hallucination Rules

1. NEVER assume resource names — always discover via CLI/API in Phase 1 before referencing in Phase 2.
2. NEVER fabricate metric names or dimensions — verify against the service documentation or --help output.
3. NEVER mix CLI commands between service versions — confirm which version/API you are targeting.
4. ALWAYS use the discovery → verify → analyze chain — every resource referenced must have been discovered first.
5. ALWAYS handle empty results gracefully — an empty response is valid data, not an error to retry.

Counter-Rationalizations

Common Pitfalls

• API versioning: Use /api/1.0/ prefix — some newer features may use /api/2.0/
• Basic Auth only: No OAuth support — always use HTTPS to protect credentials
• Pagination: Use limit and offset parameters — default limit varies by endpoint
• Trailing slashes: Some endpoints require trailing slashes — include them consistently
• Custom fields: Access via separate /custom_fields/ endpoints — not inline with main object
• DOQL: Device42 Object Query Language provides SQL-like queries for complex reporting
• Rate limits: Self-hosted — depends on appliance sizing and configuration
• Bulk operations: Use batch endpoints for mass updates — individual updates for large datasets will be slow