Azure CDN Skill

Manage Azure CDN profiles, endpoints, caching rules, custom domains, and delivery optimization.

Core Helper Functions

#!/bin/bash

# List CDN profiles
az_cdn_profiles() {
    az cdn profile list --output json 2>/dev/null
}

# List endpoints for a profile
az_cdn_endpoints() {
    local rg="$1" profile="$2"
    az cdn endpoint list --resource-group "$rg" --profile-name "$profile" --output json 2>/dev/null
}

# Get endpoint details
az_cdn_endpoint() {
    local rg="$1" profile="$2" endpoint="$3"
    az cdn endpoint show --resource-group "$rg" --profile-name "$profile" --name "$endpoint" --output json 2>/dev/null
}

MANDATORY: Discovery-First Pattern

Phase 1: Discovery

#!/bin/bash

echo "=== CDN Profiles ==="
az cdn profile list --output json 2>/dev/null | jq -r '
    .[] | "\(.name)\t\(.resourceGroup)\t\(.sku.name)\t\(.provisioningState)"
' | column -t | head -15

echo ""
echo "=== CDN Endpoints ==="
for profile in $(az cdn profile list --query '[].{n:name,rg:resourceGroup}' -o tsv 2>/dev/null); do
    NAME=$(echo "$profile" | cut -f1)
    RG=$(echo "$profile" | cut -f2)
    az cdn endpoint list --resource-group "$RG" --profile-name "$NAME" -o json 2>/dev/null | jq -r --arg p "$NAME" '
        .[] | "\($p)\t\(.name)\t\(.hostName)\t\(.isHttpAllowed)/\(.isHttpsAllowed)\t\(.provisioningState)"
    '
done | column -t | head -20

echo ""
echo "=== Custom Domains ==="
for profile in $(az cdn profile list --query '[].{n:name,rg:resourceGroup}' -o tsv 2>/dev/null); do
    NAME=$(echo "$profile" | cut -f1)
    RG=$(echo "$profile" | cut -f2)
    for ep in $(az cdn endpoint list --resource-group "$RG" --profile-name "$NAME" --query '[].name' -o tsv 2>/dev/null); do
        az cdn custom-domain list --resource-group "$RG" --profile-name "$NAME" --endpoint-name "$ep" -o json 2>/dev/null | jq -r --arg ep "$ep" '
            .[] | "\($ep)\t\(.name)\t\(.hostName)\t\(.customHttpsProvisioningState // "n/a")"
        '
    done
done | column -t | head -15

Phase 2: Analysis

#!/bin/bash
RG="${1:?Resource group required}"
PROFILE="${2:?Profile name required}"
ENDPOINT="${3:?Endpoint name required}"

echo "=== Endpoint Configuration ==="
az cdn endpoint show --resource-group "$RG" --profile-name "$PROFILE" --name "$ENDPOINT" -o json 2>/dev/null | jq '{
    hostName, isHttpAllowed, isHttpsAllowed, isCompressionEnabled,
    contentTypesToCompress: (.contentTypesToCompress | length),
    origins: [.origins[] | {name, hostName, enabled}],
    queryStringCachingBehavior, optimizationType
}'

echo ""
echo "=== Delivery Rules ==="
az cdn endpoint show --resource-group "$RG" --profile-name "$PROFILE" --name "$ENDPOINT" -o json 2>/dev/null | jq '
    .deliveryPolicy.rules[]? | {order, name, conditions: [.conditions[].name], actions: [.actions[].name]}
' | head -25

echo ""
echo "=== Origin Groups ==="
az cdn origin-group list --resource-group "$RG" --profile-name "$PROFILE" --endpoint-name "$ENDPOINT" -o json 2>/dev/null | jq -r '
    .[] | "\(.name)\t\(.healthProbeSettings.probePath // "none")\t\(.healthProbeSettings.probeIntervalInSeconds // 0)s"
' | column -t | head -10

Output Rules

• TOKEN EFFICIENCY: Target <=50 lines per output
• Use az CLI with --output json and jq for parsing
• Always specify resource group and profile name for context

Safety Rules

• Read-only by default: Use list/show commands for inspection
• Never purge endpoints without explicit user confirmation
• Custom domain HTTPS provisioning can take up to 8 hours
• Delivery rule order matters: Rules are evaluated in order of priority

Output Format

Present results as a structured report:

Managing Azure Cdn 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

Shortcut	Counter	Why
"I'll skip discovery and check known resources"	Always run Phase 1 discovery first	Resource names change, new resources appear — assumed names cause errors
"The user only asked for a quick check"	Follow the full discovery → analysis flow	Quick checks miss critical issues; structured analysis catches silent failures
"Default configuration is probably fine"	Audit configuration explicitly	Defaults often leave logging, security, and optimization features disabled
"Metrics aren't needed for this"	Always check relevant metrics when available	API/CLI responses show current state; metrics reveal trends and intermittent issues
"I don't have access to that"	Try the command and report the actual error	Assumed permission failures prevent useful investigation; actual errors are informative

Common Pitfalls

• SKU determines features: Standard Microsoft, Verizon, and Akamai have different rule engines
• Propagation delay: Changes can take up to 10 minutes to propagate to all POPs
• Compression: Must explicitly list content types to compress
• Query string caching: Default behavior varies by SKU -- verify before assuming
• Custom domain validation: CNAME or TXT record must be in place before adding custom domains