ACI Change Deployment
Golden Rule
NEVER deploy an ACI policy change without an approved ServiceNow Change Request. If there is no CR, create one first. If the CR is not approved, do not proceed.
How to Call the MCP Tools
ACI MCP Server
bashAPIC_URL=$APIC_URL USERNAME=$ACI_USERNAME PASSWORD=$ACI_PASSWORD python3 $MCP_CALL "python3 -u $ACI_MCP_SCRIPT" TOOL_NAME '{"param":"value"}'
ServiceNow MCP Server
bashpython3 $MCP_CALL "python3 -u $SERVICENOW_MCP_SCRIPT" TOOL_NAME '{"param":"value"}'
Change Workflow
Phase 1: ServiceNow Change Request Creation
Before touching the APIC, check for open P1/P2 incidents on the affected CIs and prepare a CR that documents the tenant, VRF, BD, and EPG scope. Obtain authorization to create the external ticket under the session communication rules. Discover the installed ServiceNow/APIC tool schemas before using these examples; external server versions can differ.
1A: Create the Change Request
bashpython3 $MCP_CALL "python3 -u $SERVICENOW_MCP_SCRIPT" create_change_request '{"short_description":"ACI: Create tenant prod-web with VRF, BD, and EPG","description":"Create new tenant prod-web in ACI fabric.\n\nScope:\n- Tenant: prod-web\n- VRF: prod-web-vrf (enforced)\n- BD: web-bd (subnet 10.10.1.1/24)\n- App Profile: web-app\n- EPG: web-frontend (VLAN 100)\n\nAPIC: sandboxapicdc.cisco.com\nRisk: Low - net new tenant, no impact to existing policy","type":"normal","risk":"low","impact":"low","category":"Network"}'
Save the returned change_id (sys_id) and number (e.g., CHG0030001) for all subsequent steps.
1B: Add Implementation Tasks
bashpython3 $MCP_CALL "python3 -u $SERVICENOW_MCP_SCRIPT" add_change_task '{"change_id":"CHG0030001","short_description":"Pre-change: Capture ACI fault baseline","description":"Record fault counts by severity before applying any changes"}'
bashpython3 $MCP_CALL "python3 -u $SERVICENOW_MCP_SCRIPT" add_change_task '{"change_id":"CHG0030001","short_description":"Apply: Create tenant/VRF/BD/EPG on APIC","description":"Apply ACI policy objects via APIC REST API"}'
bashpython3 $MCP_CALL "python3 -u $SERVICENOW_MCP_SCRIPT" add_change_task '{"change_id":"CHG0030001","short_description":"Post-change: Verify zero new faults","description":"Compare fault counts with baseline, verify new objects operational"}'
1C: Submit for Approval
bashpython3 $MCP_CALL "python3 -u $SERVICENOW_MCP_SCRIPT" submit_change_for_approval '{"change_id":"CHG0030001","approval_comments":"Low-risk net new tenant creation. No existing policy affected."}'
1D: Verify Approval (Required Before Proceeding)
bashpython3 $MCP_CALL "python3 -u $SERVICENOW_MCP_SCRIPT" get_change_request_details '{"change_id":"CHG0030001"}'
Proceed only when the exact intended CR has approved authorization AND its lifecycle state is Implement. An approved CR still in another lifecycle state is insufficient, as is an Implement record without approval. Verify the returned CR identifier and scope match this change. Missing, malformed, unavailable or mismatched records stop the change. If rejected, review the rejection reason:
bashpython3 $MCP_CALL "python3 -u $SERVICENOW_MCP_SCRIPT" list_change_requests '{"query":"number=CHG0030001","limit":1}'
Phase 2: Pre-Change Baseline
Capture the current fabric state so you can detect any regression after the change.
2A: Fault Baseline
bashAPIC_URL=$APIC_URL USERNAME=$ACI_USERNAME PASSWORD=$ACI_PASSWORD python3 $MCP_CALL "python3 -u $ACI_MCP_SCRIPT" faults '{}'
Count and record faults by severity:
Pre-Change Fault Baseline -------------------------- Critical: 0 Major: 2 Minor: 7 Warning: 12 Total: 21
Store these counts -- they are the rollback reference.
2B: Health Score Baseline
bashAPIC_URL=$APIC_URL USERNAME=$ACI_USERNAME PASSWORD=$ACI_PASSWORD python3 $MCP_CALL "python3 -u $ACI_MCP_SCRIPT" health '{}'
Record the overall fabric health score (e.g., 97/100).
2C: Existing Tenant Inventory
bashAPIC_URL=$APIC_URL USERNAME=$ACI_USERNAME PASSWORD=$ACI_PASSWORD python3 $MCP_CALL "python3 -u $ACI_MCP_SCRIPT" tenants_get '{}'
Confirm the target tenant does not already exist (for create operations) or does exist (for modify operations).
2D: Update CR with Baseline
bashpython3 $MCP_CALL "python3 -u $SERVICENOW_MCP_SCRIPT" update_change_request '{"change_id":"CHG0030001","work_notes":"Pre-change baseline captured:\n- Faults: 0 critical, 2 major, 7 minor, 12 warning (21 total)\n- Health score: 97/100\n- Tenant prod-web does not exist (confirmed)\n\nProceeding with implementation."}'
Phase 3: Apply ACI Policy Changes
Apply changes one object at a time, in dependency order: Tenant -> VRF -> BD -> App Profile -> EPG.
3A: Create Tenant
bashAPIC_URL=$APIC_URL USERNAME=$ACI_USERNAME PASSWORD=$ACI_PASSWORD python3 $MCP_CALL "python3 -u $ACI_MCP_SCRIPT" tenants_post '{"name":"prod-web","descr":"Production web services tenant"}'
Verify the response indicates success before proceeding.
3B: Create VRF
bashAPIC_URL=$APIC_URL USERNAME=$ACI_USERNAME PASSWORD=$ACI_PASSWORD python3 $MCP_CALL "python3 -u $ACI_MCP_SCRIPT" fvCtx_post '{"tenant":"prod-web","name":"prod-web-vrf","descr":"Production web VRF","pcEnfPref":"enforced"}'
3C: Create Bridge Domain
bashAPIC_URL=$APIC_URL USERNAME=$ACI_USERNAME PASSWORD=$ACI_PASSWORD python3 $MCP_CALL "python3 -u $ACI_MCP_SCRIPT" fvBD_post '{"tenant":"prod-web","name":"web-bd","descr":"Web tier bridge domain","vrf":"prod-web-vrf"}'
After creating the BD, configure the subnet (the exact tool depends on your ACI MCP server capabilities -- it may be a separate subnet tool or a parameter on the BD creation).
3D: Create Application Profile
bashAPIC_URL=$APIC_URL USERNAME=$ACI_USERNAME PASSWORD=$ACI_PASSWORD python3 $MCP_CALL "python3 -u $ACI_MCP_SCRIPT" fvAp_post '{"tenant":"prod-web","name":"web-app","descr":"Web application profile"}'
3E: Create Endpoint Group
bashAPIC_URL=$APIC_URL USERNAME=$ACI_USERNAME PASSWORD=$ACI_PASSWORD python3 $MCP_CALL "python3 -u $ACI_MCP_SCRIPT" fvAEPg_post '{"tenant":"prod-web","ap":"web-app","name":"web-frontend","descr":"Web frontend EPG","bd":"web-bd"}'
After each object creation: Check the APIC response for errors. If any call fails, STOP and do not proceed to the next object.
Phase 4: Post-Change Verification
4A: Fault Delta Check
bashAPIC_URL=$APIC_URL USERNAME=$ACI_USERNAME PASSWORD=$ACI_PASSWORD python3 $MCP_CALL "python3 -u $ACI_MCP_SCRIPT" faults '{}'
Compare with Phase 2A baseline:
Post-Change Fault Comparison ------------------------------ Pre Post Delta Critical: 0 0 0 Major: 2 2 0 Minor: 7 7 0 Warning: 12 12 0 Total: 21 21 0 (no new faults)
Decision matrix:
| Fault Delta | Action |
|---|---|
| No new faults | PASS -- proceed to CR closure |
| New warning/minor only | PASS with note -- document in CR |
| New major faults | INVESTIGATE -- may need rollback |
| New critical faults | ROLLBACK immediately |
4B: Health Score Delta
bashAPIC_URL=$APIC_URL USERNAME=$ACI_USERNAME PASSWORD=$ACI_PASSWORD python3 $MCP_CALL "python3 -u $ACI_MCP_SCRIPT" health '{}'
Flags:
- Health score unchanged or improved -> PASS
- Health score dropped 1-5 points -> WARNING: Investigate
- Health score dropped > 5 points -> CRITICAL: Consider rollback
4C: Verify Created Objects
Confirm each object exists and is in the expected state:
bashAPIC_URL=$APIC_URL USERNAME=$ACI_USERNAME PASSWORD=$ACI_PASSWORD python3 $MCP_CALL "python3 -u $ACI_MCP_SCRIPT" tenants_get '{}'
bashAPIC_URL=$APIC_URL USERNAME=$ACI_USERNAME PASSWORD=$ACI_PASSWORD python3 $MCP_CALL "python3 -u $ACI_MCP_SCRIPT" fvCtx_get '{}'
bashAPIC_URL=$APIC_URL USERNAME=$ACI_USERNAME PASSWORD=$ACI_PASSWORD python3 $MCP_CALL "python3 -u $ACI_MCP_SCRIPT" fvBD_get '{}'
bashAPIC_URL=$APIC_URL USERNAME=$ACI_USERNAME PASSWORD=$ACI_PASSWORD python3 $MCP_CALL "python3 -u $ACI_MCP_SCRIPT" fvAp_get '{}'
bashAPIC_URL=$APIC_URL USERNAME=$ACI_USERNAME PASSWORD=$ACI_PASSWORD python3 $MCP_CALL "python3 -u $ACI_MCP_SCRIPT" fvAEPg_get '{}'
Verify the new tenant, VRF, BD, app profile, and EPG all appear in the returned data with correct attributes.
Phase 5: Rollback Procedure (If Needed)
If the fault count increases or the health score drops significantly, roll back in reverse dependency order: EPG -> App Profile -> BD -> VRF -> Tenant.
Rollback is required when:
- Any new critical fault appears
- Any new major fault directly related to the change
- Health score drops more than 5 points
- Created objects are in a faulted state
After rollback, re-run Phase 4A and 4B to confirm the fabric returned to baseline.
Update the CR with rollback details:
bashpython3 $MCP_CALL "python3 -u $SERVICENOW_MCP_SCRIPT" update_change_request '{"change_id":"CHG0030001","work_notes":"ROLLBACK PERFORMED: New critical fault detected after EPG creation. All objects removed in reverse order. Fabric returned to baseline (21 faults, health 97/100). Root cause investigation needed.","state":"canceled"}'
Phase 6: CR Closure or Escalation
6A: Successful Change -- Close the CR
bashpython3 $MCP_CALL "python3 -u $SERVICENOW_MCP_SCRIPT" update_change_request '{"change_id":"CHG0030001","state":"closed","work_notes":"Change completed successfully.\n\nPost-change verification:\n- Fault delta: 0 new faults\n- Health score: 97/100 (unchanged)\n- All objects verified operational:\n - Tenant: prod-web\n - VRF: prod-web-vrf (enforced)\n - BD: web-bd\n - App Profile: web-app\n - EPG: web-frontend\n\nChange implementation complete."}'
6B: Failed Change -- Escalate
If rollback was needed or issues were found:
bashpython3 $MCP_CALL "python3 -u $SERVICENOW_MCP_SCRIPT" update_change_request '{"change_id":"CHG0030001","work_notes":"Change failed: fault delta detected. Rollback completed. Escalating for root cause analysis.","state":"canceled"}'
Phase 7: GAIT Full Session Audit
Record the complete change session in GAIT for compliance:
bashpython3 $MCP_CALL "python3 -u $GAIT_MCP_SCRIPT" gait_record_turn '{"user_text":"Example only: replace with the actual authorized request.","assistant_text":"ACI change deployment completed.\n\nCR: CHG0030001 - Create tenant prod-web\nAPIC: sandboxapicdc.cisco.com\nResult: SUCCESS\n\nObjects created: tenant prod-web, VRF prod-web-vrf, BD web-bd, AP web-app, EPG web-frontend\nPre-change faults: 21 (0 critical)\nPost-change faults: 21 (0 critical) - delta: 0\nHealth score: 97/100 (unchanged)\nRollback required: No\nCR Status: Closed","artifacts":[]}'
Complete End-to-End Example
Example: Create a New Production Tenant with Full Workflow
This example walks through creating tenant "prod-web" with a VRF, bridge domain, application profile, and EPG:
bash# Step 1: Create ServiceNow CR python3 $MCP_CALL "python3 -u $SERVICENOW_MCP_SCRIPT" create_change_request '{"short_description":"ACI: Create tenant prod-web with VRF/BD/EPG","type":"normal","risk":"low","impact":"low","category":"Network","description":"Net new tenant for web services. Scope: tenant prod-web, VRF prod-web-vrf, BD web-bd (10.10.1.0/24), AP web-app, EPG web-frontend."}' # Step 2: Submit CR for approval python3 $MCP_CALL "python3 -u $SERVICENOW_MCP_SCRIPT" submit_change_for_approval '{"change_id":"<sys_id_from_step_1>","approval_comments":"Low risk, net new tenant."}' # Step 3: Verify CR approved (MUST pass before continuing) python3 $MCP_CALL "python3 -u $SERVICENOW_MCP_SCRIPT" get_change_request_details '{"change_id":"<sys_id_from_step_1>"}' # Step 4: Capture pre-change baselines APIC_URL=$APIC_URL USERNAME=$ACI_USERNAME PASSWORD=$ACI_PASSWORD python3 $MCP_CALL "python3 -u $ACI_MCP_SCRIPT" faults '{}' APIC_URL=$APIC_URL USERNAME=$ACI_USERNAME PASSWORD=$ACI_PASSWORD python3 $MCP_CALL "python3 -u $ACI_MCP_SCRIPT" health '{}' APIC_URL=$APIC_URL USERNAME=$ACI_USERNAME PASSWORD=$ACI_PASSWORD python3 $MCP_CALL "python3 -u $ACI_MCP_SCRIPT" tenants_get '{}' # Step 5: Apply changes (dependency order) APIC_URL=$APIC_URL USERNAME=$ACI_USERNAME PASSWORD=$ACI_PASSWORD python3 $MCP_CALL "python3 -u $ACI_MCP_SCRIPT" tenants_post '{"name":"prod-web","descr":"Production web services"}' APIC_URL=$APIC_URL USERNAME=$ACI_USERNAME PASSWORD=$ACI_PASSWORD python3 $MCP_CALL "python3 -u $ACI_MCP_SCRIPT" fvCtx_post '{"tenant":"prod-web","name":"prod-web-vrf","pcEnfPref":"enforced"}' APIC_URL=$APIC_URL USERNAME=$ACI_USERNAME PASSWORD=$ACI_PASSWORD python3 $MCP_CALL "python3 -u $ACI_MCP_SCRIPT" fvBD_post '{"tenant":"prod-web","name":"web-bd","vrf":"prod-web-vrf"}' APIC_URL=$APIC_URL USERNAME=$ACI_USERNAME PASSWORD=$ACI_PASSWORD python3 $MCP_CALL "python3 -u $ACI_MCP_SCRIPT" fvAp_post '{"tenant":"prod-web","name":"web-app"}' APIC_URL=$APIC_URL USERNAME=$ACI_USERNAME PASSWORD=$ACI_PASSWORD python3 $MCP_CALL "python3 -u $ACI_MCP_SCRIPT" fvAEPg_post '{"tenant":"prod-web","ap":"web-app","name":"web-frontend","bd":"web-bd"}' # Step 6: Post-change verification APIC_URL=$APIC_URL USERNAME=$ACI_USERNAME PASSWORD=$ACI_PASSWORD python3 $MCP_CALL "python3 -u $ACI_MCP_SCRIPT" faults '{}' APIC_URL=$APIC_URL USERNAME=$ACI_USERNAME PASSWORD=$ACI_PASSWORD python3 $MCP_CALL "python3 -u $ACI_MCP_SCRIPT" health '{}' APIC_URL=$APIC_URL USERNAME=$ACI_USERNAME PASSWORD=$ACI_PASSWORD python3 $MCP_CALL "python3 -u $ACI_MCP_SCRIPT" tenants_get '{}' APIC_URL=$APIC_URL USERNAME=$ACI_USERNAME PASSWORD=$ACI_PASSWORD python3 $MCP_CALL "python3 -u $ACI_MCP_SCRIPT" fvCtx_get '{}' APIC_URL=$APIC_URL USERNAME=$ACI_USERNAME PASSWORD=$ACI_PASSWORD python3 $MCP_CALL "python3 -u $ACI_MCP_SCRIPT" fvBD_get '{}' APIC_URL=$APIC_URL USERNAME=$ACI_USERNAME PASSWORD=$ACI_PASSWORD python3 $MCP_CALL "python3 -u $ACI_MCP_SCRIPT" fvAEPg_get '{}' # Step 7: Close CR (if successful) python3 $MCP_CALL "python3 -u $SERVICENOW_MCP_SCRIPT" update_change_request '{"change_id":"<sys_id_from_step_1>","state":"closed","work_notes":"Change completed. Fault delta: 0. Health unchanged. All objects verified."}' # Step 8: GAIT audit trail python3 $MCP_CALL "python3 -u $GAIT_MCP_SCRIPT" gait_record_turn '{"user_text":"Example only: replace with the actual authorized request.","assistant_text":"ACI change CHG0030001 completed successfully. Tenant prod-web created with VRF/BD/AP/EPG. Zero fault delta. CR closed.","artifacts":[]}'
Change Report Format
After every change, produce a change report:
ACI Change Report ================== CR: CHG0030001 - Create tenant prod-web APIC: sandboxapicdc.cisco.com Timestamp: YYYY-MM-DD HH:MM UTC Operator: NetClaw AI Agent Change Scope ------------- Tenant: prod-web (NEW) VRF: prod-web-vrf (enforced) Bridge Domain: web-bd (subnet 10.10.1.1/24) App Profile: web-app EPG: web-frontend Pre-Change State ----------------- Faults: 0 critical, 2 major, 7 minor, 12 warning (21 total) Health Score: 97/100 Tenant Count: 5 Post-Change State ------------------ Faults: 0 critical, 2 major, 7 minor, 12 warning (21 total) Health Score: 97/100 Tenant Count: 6 (+1 prod-web) Fault Delta: 0 new faults Verification: PASSED -- all objects operational Rollback: Not required CR Status: Closed
Integration with Other Skills
- Use aci-fabric-audit to run a full fabric audit before and after the change window
- Use markmap-viz to visualize the updated tenant hierarchy after the change
- Use drawio-diagram to generate an updated fabric topology including the new policy objects
Audit examples are illustrative. Replace request, outcomes, identifiers and counts
with observed session evidence; do not record these example results as facts.
Inspect MCP isError, returned ok, and the recorded turn with gait_show when
validating a new client/schema. Follow gait-session-tracking for branch checkout.
