catc-troubleshoot

SKILL.md

Catalyst Center Troubleshooting Workflows

Structured troubleshooting methodology using Cisco Catalyst Center (formerly DNA Center) as the primary diagnostic platform, with escalation to pyATS CLI-level tools when the controller APIs are insufficient. This skill provides decision trees, triage procedures, and escalation paths for the most common network issues surfaced through Catalyst Center.

Catalyst Center MCP Server

All Catalyst Center tool calls use this invocation pattern:

CCC_HOST=$CCC_HOST CCC_USER=$CCC_USER CCC_PWD=$CCC_PWD python3 -u $CATC_MCP_SCRIPT

Variable shorthand used throughout this document:

CATC_CMD="CCC_HOST=$CCC_HOST CCC_USER=$CCC_USER CCC_PWD=$CCC_PWD python3 -u $CATC_MCP_SCRIPT"

How to Call Tools

Use the $MCP_CALL protocol handler to invoke MCP tools:

CCC_HOST=$CCC_HOST CCC_USER=$CCC_USER CCC_PWD=$CCC_PWD python3 $MCP_CALL "python3 -u $CATC_MCP_SCRIPT" TOOL_NAME 'ARGS_JSON'

When to Use

  • Help desk escalation: user reports "I can't connect"
  • NOC alert: device unreachable in Catalyst Center
  • Client connectivity complaints (wired or wireless)
  • Site-wide outage affecting multiple users
  • Wireless roaming issues or poor signal complaints
  • Interface down investigations
  • Post-change verification when something goes wrong
  • Correlation between Catalyst Center data and live device state via pyATS

Troubleshooting Principles

  1. Define the problem -- What exactly is reported? Single user, multiple users, entire site? Wired or wireless? When did it start?
  2. Scope the impact -- Use Catalyst Center client counts and device reachability to quantify: how many clients affected? How many devices unreachable?
  3. Gather data from the controller -- Catalyst Center provides a controller-level view that covers hundreds of devices simultaneously. Start here.
  4. Correlate with live device state -- When Catalyst Center data is stale or insufficient, escalate to pyATS for real-time CLI data.
  5. Isolate the fault domain -- Is it the client, the access layer, the distribution/core, or a WAN/upstream issue?
  6. Resolve and verify -- Fix the issue, confirm via both Catalyst Center and pyATS, document.

Issue 1: Device Unreachable

Trigger: Catalyst Center shows one or more devices with reachabilityStatus: Unreachable.

Decision Tree

Device Unreachable in Catalyst Center
|
+-- Step 1: Confirm the scope
|   How many devices are unreachable?
|   Are they at the same site?
|   |
|   +-- Single device unreachable
|   |   --> Go to "Single Device Investigation"
|   |
|   +-- Multiple devices at same site
|   |   --> Go to "Site-Wide Outage Triage" (Issue 4)
|   |
|   +-- Multiple devices across sites
|       --> Go to "Catalyst Center or Upstream Issue"
|
+-- Step 2: Single Device Investigation
|   |
|   +-- Check device details in CatC
|   +-- Check last update time
|   +-- Check collection status and error code
|   +-- Attempt pyATS connectivity test
|   |
|   +-- pyATS connects successfully?
|   |   |
|   |   +-- YES: CatC polling issue (SNMP/NETCONF credentials, ACL)
|   |   +-- NO: Device is truly unreachable
|   |       |
|   |       +-- Ping from adjacent device (pyATS)
|   |       +-- Check upstream interface state
|   |       +-- Check ARP/MAC table on upstream switch
|   |       +-- Physical layer: power, cable, SFP

Step 1: Identify All Unreachable Devices

CCC_HOST=$CCC_HOST CCC_USER=$CCC_USER CCC_PWD=$CCC_PWD python3 $MCP_CALL "python3 -u $CATC_MCP_SCRIPT" fetch_devices '{"reachabilityStatus":["Unreachable"]}'

Record for each device: hostname, managementIpAddress, platformId, locationName, lastUpdated, collectionStatus, errorCode.

Step 2: Check If It Is Site-Localized

# Get the site hierarchy to understand the topology
CCC_HOST=$CCC_HOST CCC_USER=$CCC_USER CCC_PWD=$CCC_PWD python3 $MCP_CALL "python3 -u $CATC_MCP_SCRIPT" fetch_sites '{}'

Group unreachable devices by locationName. If multiple devices at the same site are unreachable, skip to Issue 4 (Site-Wide Outage).

Step 3: Inspect the Specific Device

CCC_HOST=$CCC_HOST CCC_USER=$CCC_USER CCC_PWD=$CCC_PWD python3 $MCP_CALL "python3 -u $CATC_MCP_SCRIPT" fetch_devices '{"hostname":["UNREACHABLE-SW-01"]}'

Analyze:

  • lastUpdated -- How long has it been unreachable? Minutes = recent event. Hours/days = chronic issue.
  • collectionStatus -- Could Not Synchronize vs Partial Collection Failure vs Managed
  • errorCode -- Specific error from Catalyst Center's collection engine

Step 4: Check Interfaces on the Unreachable Device (If CatC Has Cached Data)

CCC_HOST=$CCC_HOST CCC_USER=$CCC_USER CCC_PWD=$CCC_PWD python3 $MCP_CALL "python3 -u $CATC_MCP_SCRIPT" fetch_interfaces '{"device_id":"<UUID-from-step-3>"}'

NOTE: This returns the last-known interface state. If the device became unreachable recently, this data may still reflect the pre-failure state. Look for interfaces that were already showing errors before the device went dark.

Step 5: Escalate to pyATS for Live Validation

When $PYATS_MCP_SCRIPT and $PYATS_TESTBED_PATH are available and the device is in the pyATS testbed:

# Attempt to connect and get basic state
PYATS_TESTBED_PATH=$PYATS_TESTBED_PATH python3 $MCP_CALL "python3 -u $PYATS_MCP_SCRIPT" pyats_run_show_command '{"device_name":"UNREACHABLE-SW-01","command":"show ip interface brief"}'

If pyATS connects but CatC cannot reach the device:

  • The device is alive but Catalyst Center's polling is blocked
  • Check SNMP community strings, NETCONF/RESTCONF configuration
  • Check if an ACL on the device is blocking the CatC management IP
  • Verify the management VRF routing to the CatC appliance

If pyATS also cannot connect:

  • The device is truly unreachable from the management network
  • Ping from an adjacent device in pyATS:
PYATS_TESTBED_PATH=$PYATS_TESTBED_PATH python3 $MCP_CALL "python3 -u $PYATS_MCP_SCRIPT" pyats_ping_from_network_device '{"device_name":"UPSTREAM-SW-01","command":"ping 10.1.10.1"}'
  • Check the upstream switch's interface to the unreachable device:
PYATS_TESTBED_PATH=$PYATS_TESTBED_PATH python3 $MCP_CALL "python3 -u $PYATS_MCP_SCRIPT" pyats_run_show_command '{"device_name":"UPSTREAM-SW-01","command":"show interfaces GigabitEthernet1/0/1"}'
  • Check ARP and MAC table on the upstream switch:
PYATS_TESTBED_PATH=$PYATS_TESTBED_PATH python3 $MCP_CALL "python3 -u $PYATS_MCP_SCRIPT" pyats_run_show_command '{"device_name":"UPSTREAM-SW-01","command":"show arp"}'

Common Root Causes: Device Unreachable

Root Cause CatC Indicators pyATS Indicators Resolution
Device powered off Unreachable, no updates Connection refused Check power, PDU, UPS
Management interface down Unreachable Cannot SSH Verify mgmt interface config via console
SNMP credential mismatch Partial Collection Failure pyATS connects OK Fix SNMP community on device or CatC
ACL blocking CatC Unreachable from CatC pyATS connects OK Update ACL to permit CatC management IPs
Routing issue to mgmt subnet Unreachable Ping fails from adjacent device Check routing table, management VRF
Upstream link failure Multiple devices unreachable Upstream interface down Physical layer: cable, SFP, port
Device crash/reload Recently unreachable Boot messages in logs Check show logging, show version uptime

Issue 2: Client Connectivity Problems

Trigger: User reports cannot connect to the network, slow connectivity, or intermittent drops.

Decision Tree

Client Connectivity Issue
|
+-- Step 1: Identify the client
|   Do we have the MAC address, IP address, or username?
|   |
|   +-- MAC known --> get_client_details_by_mac
|   +-- IP known --> get_clients_list with ipv4_address filter, then get details by MAC
|   +-- Only username/location --> get_clients_list filtered by site
|
+-- Step 2: Is the client visible in CatC?
|   |
|   +-- YES: Client is associating/authenticating
|   |   |
|   |   +-- Check health score
|   |   +-- Wired or wireless?
|   |   |   |
|   |   |   +-- WIRED --> Check connected switch port, VLAN, duplex
|   |   |   +-- WIRELESS --> Check RSSI, SNR, band, AP, SSID
|   |   |
|   |   +-- Check IP assignment (DHCP working?)
|   |   +-- Check connected network device status
|   |
|   +-- NO: Client not visible
|       |
|       +-- Is the access switch/AP reachable?
|       +-- Is the client physically connected (cable/Wi-Fi enabled)?
|       +-- Is 802.1X/MAB failing? (check ISE if available)
|       +-- Is the SSID broadcasting?

Step 1: Get Time Range

CCC_HOST=$CCC_HOST CCC_USER=$CCC_USER CCC_PWD=$CCC_PWD python3 $MCP_CALL "python3 -u $CATC_MCP_SCRIPT" get_api_compatible_time_range '{"time_window":"last 4 hours"}'

Step 2: Look Up the Client

By MAC address (preferred):

CCC_HOST=$CCC_HOST CCC_USER=$CCC_USER CCC_PWD=$CCC_PWD python3 $MCP_CALL "python3 -u $CATC_MCP_SCRIPT" get_client_details_by_mac '{"client_mac_address":"AA:BB:CC:DD:EE:FF","start_time":1705312800000,"end_time":1705399200000,"view":["Wireless","WirelessHealth"]}'

By IP address:

CCC_HOST=$CCC_HOST CCC_USER=$CCC_USER CCC_PWD=$CCC_PWD python3 $MCP_CALL "python3 -u $CATC_MCP_SCRIPT" get_clients_list '{"start_time":1705312800000,"end_time":1705399200000,"ipv4_address":["10.1.50.42"]}'

Step 3: Analyze Client Data

For wired clients, check:

  • connectedNetworkDeviceName -- Which switch is the client on?
  • connectedNetworkDeviceInterfaceName -- Which port?
  • vlanId -- Correct VLAN assignment?
  • ipv4Address -- Valid IP? Or APIPA (169.254.x.x) indicating DHCP failure?
  • healthScore -- Score 0-10. Below 7 = issue.

For wireless clients, check:

  • ssid -- Connected to the correct SSID?
  • band -- 2.4 GHz or 5 GHz?
  • rssi -- Signal strength (see RSSI table below)
  • snr -- Signal-to-noise ratio
  • dataRate -- Current data rate in Mbps
  • connectedNetworkDeviceName -- Which AP?
  • healthScore -- Client health score

Step 4: Check the Access Device

If the client's access switch or AP shows issues:

# Is the access device reachable?
CCC_HOST=$CCC_HOST CCC_USER=$CCC_USER CCC_PWD=$CCC_PWD python3 $MCP_CALL "python3 -u $CATC_MCP_SCRIPT" fetch_devices '{"hostname":["ACC-SW-01"]}'

# Get the switch's interfaces to check the client-facing port
CCC_HOST=$CCC_HOST CCC_USER=$CCC_USER CCC_PWD=$CCC_PWD python3 $MCP_CALL "python3 -u $CATC_MCP_SCRIPT" fetch_interfaces '{"device_id":"<switch-UUID>"}'

Step 5: Escalate to pyATS for Switch-Port Level Troubleshooting

When CatC data is insufficient (e.g., you need to check port security, 802.1X session state, or MAC address table):

# Check the specific switchport
PYATS_TESTBED_PATH=$PYATS_TESTBED_PATH python3 $MCP_CALL "python3 -u $PYATS_MCP_SCRIPT" pyats_run_show_command '{"device_name":"ACC-SW-01","command":"show interfaces GigabitEthernet1/0/15"}'

# Check authentication sessions (802.1X/MAB)
PYATS_TESTBED_PATH=$PYATS_TESTBED_PATH python3 $MCP_CALL "python3 -u $PYATS_MCP_SCRIPT" pyats_run_show_command '{"device_name":"ACC-SW-01","command":"show authentication sessions"}'

# Check MAC address table for the client
PYATS_TESTBED_PATH=$PYATS_TESTBED_PATH python3 $MCP_CALL "python3 -u $PYATS_MCP_SCRIPT" pyats_run_show_command '{"device_name":"ACC-SW-01","command":"show mac address-table"}'

# Check DHCP snooping bindings
PYATS_TESTBED_PATH=$PYATS_TESTBED_PATH python3 $MCP_CALL "python3 -u $PYATS_MCP_SCRIPT" pyats_run_show_command '{"device_name":"ACC-SW-01","command":"show ip dhcp snooping binding"}'

# Check port-security
PYATS_TESTBED_PATH=$PYATS_TESTBED_PATH python3 $MCP_CALL "python3 -u $PYATS_MCP_SCRIPT" pyats_run_show_command '{"device_name":"ACC-SW-01","command":"show port-security"}'

Common Root Causes: Client Connectivity

Root Cause CatC Indicators pyATS/CLI Indicators Resolution
DHCP exhaustion Client has 169.254.x.x IP show ip dhcp pool shows 0 free Expand DHCP scope or reduce lease time
Port security violation Client not visible err-disabled state on port Clear port-security, investigate
802.1X failure Client not visible Authentication failed in ISE Check credentials, certificate, RADIUS
Wrong VLAN Client visible but no connectivity Port in wrong VLAN Correct VLAN assignment
Duplex mismatch Poor health score (wired) Half-duplex on one end Set both ends to auto or match manually
Wireless: low RSSI Low health score, low RSSI N/A (wireless) Move closer to AP, add AP coverage
Wireless: co-channel Intermittent drops N/A (wireless) Adjust channel plan, reduce AP power
AP overloaded Multiple clients with issues N/A (wireless) Load balance, add AP capacity
Upstream link failure Multiple clients affected Interface down on distribution Physical layer or routing issue

Issue 3: Interface Down Analysis

Trigger: Catalyst Center shows interfaces in admin up / operationally down state, or CatC alerts on interface status changes.

Step 1: Get All Interfaces on the Device

# Find the device first
CCC_HOST=$CCC_HOST CCC_USER=$CCC_USER CCC_PWD=$CCC_PWD python3 $MCP_CALL "python3 -u $CATC_MCP_SCRIPT" fetch_devices '{"hostname":["DIST-SW-01"]}'

# Fetch interfaces
CCC_HOST=$CCC_HOST CCC_USER=$CCC_USER CCC_PWD=$CCC_PWD python3 $MCP_CALL "python3 -u $CATC_MCP_SCRIPT" fetch_interfaces '{"device_id":"<UUID>"}'

Step 2: Identify Problem Interfaces

Filter the interface response for:

  • adminStatus: "UP" AND status: "down" -- Operationally failed interfaces (admin enabled but link is down)
  • High error counters in the interface data
  • Interfaces with no description (potential unused/misconfigured ports)

Step 3: Classify the Interface

Interface Type Impact Urgency
Uplink to distribution/core CRITICAL: Affects all downstream devices and clients Immediate
Inter-switch link (trunk) HIGH: May break VLAN spanning, STP reconvergence Immediate
Access port (user-facing) MEDIUM: Single user affected Standard
Management interface HIGH: Loses management access to the device Urgent
Loopback HIGH if used for routing (OSPF RID, BGP update-source) Urgent

Step 4: Escalate to pyATS for Detailed Interface Diagnostics

# Detailed interface statistics
PYATS_TESTBED_PATH=$PYATS_TESTBED_PATH python3 $MCP_CALL "python3 -u $PYATS_MCP_SCRIPT" pyats_run_show_command '{"device_name":"DIST-SW-01","command":"show interfaces TenGigabitEthernet1/0/1"}'

# Check for recent log messages about the interface
PYATS_TESTBED_PATH=$PYATS_TESTBED_PATH python3 $MCP_CALL "python3 -u $PYATS_MCP_SCRIPT" pyats_show_logging '{"device_name":"DIST-SW-01"}'

# Check SFP/transceiver status
PYATS_TESTBED_PATH=$PYATS_TESTBED_PATH python3 $MCP_CALL "python3 -u $PYATS_MCP_SCRIPT" pyats_run_show_command '{"device_name":"DIST-SW-01","command":"show interfaces transceiver"}'

# Check EtherChannel status if applicable
PYATS_TESTBED_PATH=$PYATS_TESTBED_PATH python3 $MCP_CALL "python3 -u $PYATS_MCP_SCRIPT" pyats_run_show_command '{"device_name":"DIST-SW-01","command":"show etherchannel summary"}'

# Check spanning-tree for blocked ports
PYATS_TESTBED_PATH=$PYATS_TESTBED_PATH python3 $MCP_CALL "python3 -u $PYATS_MCP_SCRIPT" pyats_run_show_command '{"device_name":"DIST-SW-01","command":"show spanning-tree"}'

Interface Down Root Causes

Symptom CatC Data CLI Investigation Likely Cause
admin UP, oper DOWN Status mismatch in CatC No link pulse on interface Bad cable, SFP, remote end shut
CRC errors incrementing Error counters in interface data show interfaces CRC count Faulty cable, bad SFP, duplex mismatch
Err-disabled Port not visible or shows errors show interfaces status err-disabled Port-security, BPDU guard, storm-control
Flapping (up/down cycles) Multiple status changes show logging UPDOWN messages Loose cable, auto-negotiation failure
STP blocked Port up but no traffic show spanning-tree BLK state STP topology issue, loop detected

Issue 4: Site-Wide Outage Triage

Trigger: Multiple users at a single site report connectivity loss, or Catalyst Center shows multiple devices unreachable at the same location.

Decision Tree

Site-Wide Outage
|
+-- Step 1: Quantify the impact
|   How many devices unreachable at this site?
|   How many clients affected?
|   |
|   +-- ALL devices unreachable at site
|   |   --> WAN link failure, upstream router, or site power outage
|   |
|   +-- SOME devices unreachable
|   |   --> Distribution layer or IDF/MDF issue
|   |
|   +-- Devices reachable but clients can't connect
|       --> DHCP, VLAN, wireless controller, or authentication issue
|
+-- Step 2: Identify the failure boundary
|   Which devices ARE still reachable?
|   What is the common upstream for the failed devices?
|
+-- Step 3: Investigate the upstream device
|   Check interfaces, routing, logs on the common upstream
|
+-- Step 4: Resolve and verify
    Fix the issue, confirm all devices come back, verify client counts recover

Step 1: Assess Site Device Status

# Get all devices at the affected site
CCC_HOST=$CCC_HOST CCC_USER=$CCC_USER CCC_PWD=$CCC_PWD python3 $MCP_CALL "python3 -u $CATC_MCP_SCRIPT" fetch_devices '{"locationName":["Global/USA/NYC/Floor3"]}'

Categorize the results:

  • Count reachable vs unreachable devices
  • Identify device roles (ACCESS, DISTRIBUTION, CORE)
  • If the distribution switch is unreachable, all downstream access switches will also be unreachable

Step 2: Check Client Impact

# Get time range
CCC_HOST=$CCC_HOST CCC_USER=$CCC_USER CCC_PWD=$CCC_PWD python3 $MCP_CALL "python3 -u $CATC_MCP_SCRIPT" get_api_compatible_time_range '{"time_window":"last 1 hours"}'

# Count clients at the affected site NOW
CCC_HOST=$CCC_HOST CCC_USER=$CCC_USER CCC_PWD=$CCC_PWD python3 $MCP_CALL "python3 -u $CATC_MCP_SCRIPT" get_clients_count '{"start_time":1705312800000,"end_time":1705399200000,"site_hierarchy":["Global/USA/NYC/Floor3"]}'

# Compare with a baseline (e.g., same time window yesterday)
CCC_HOST=$CCC_HOST CCC_USER=$CCC_USER CCC_PWD=$CCC_PWD python3 $MCP_CALL "python3 -u $CATC_MCP_SCRIPT" get_api_compatible_time_range '{"time_window":"yesterday"}'

Impact assessment:

  • Current client count vs expected baseline
  • If client count dropped to 0 or near-0: complete site outage
  • If client count dropped by 50%: partial outage (one IDF or floor affected)

Step 3: Find the Failure Boundary

Check the upstream/distribution devices that serve the affected site:

# Check the distribution switch
CCC_HOST=$CCC_HOST CCC_USER=$CCC_USER CCC_PWD=$CCC_PWD python3 $MCP_CALL "python3 -u $CATC_MCP_SCRIPT" fetch_devices '{"hostname":["DIST-SW-NYC"]}'

# Check its interfaces
CCC_HOST=$CCC_HOST CCC_USER=$CCC_USER CCC_PWD=$CCC_PWD python3 $MCP_CALL "python3 -u $CATC_MCP_SCRIPT" fetch_interfaces '{"device_id":"<DIST-UUID>"}'

Step 4: Escalate to pyATS for the Reachable Upstream

If the distribution/core device is still reachable:

# Check all interfaces on the distribution switch
PYATS_TESTBED_PATH=$PYATS_TESTBED_PATH python3 $MCP_CALL "python3 -u $PYATS_MCP_SCRIPT" pyats_run_show_command '{"device_name":"DIST-SW-NYC","command":"show ip interface brief"}'

# Check routing table -- are routes to the affected site present?
PYATS_TESTBED_PATH=$PYATS_TESTBED_PATH python3 $MCP_CALL "python3 -u $PYATS_MCP_SCRIPT" pyats_run_show_command '{"device_name":"DIST-SW-NYC","command":"show ip route"}'

# Check OSPF/BGP adjacencies
PYATS_TESTBED_PATH=$PYATS_TESTBED_PATH python3 $MCP_CALL "python3 -u $PYATS_MCP_SCRIPT" pyats_run_show_command '{"device_name":"DIST-SW-NYC","command":"show ip ospf neighbor"}'

# Check for recent events in the logs
PYATS_TESTBED_PATH=$PYATS_TESTBED_PATH python3 $MCP_CALL "python3 -u $PYATS_MCP_SCRIPT" pyats_show_logging '{"device_name":"DIST-SW-NYC"}'

# Ping the unreachable access switches from the distribution
PYATS_TESTBED_PATH=$PYATS_TESTBED_PATH python3 $MCP_CALL "python3 -u $PYATS_MCP_SCRIPT" pyats_ping_from_network_device '{"device_name":"DIST-SW-NYC","command":"ping 10.1.30.1"}'

Site Outage Root Causes

Scope Likely Cause Key Evidence Resolution
All devices + all clients Site power outage All devices unreachable, no response to pings Dispatch facilities team, check UPS/PDU
All devices + all clients WAN link failure Edge router reachable but uplink down Check ISP, activate backup WAN if available
One floor/IDF Distribution switch failure Dist switch unreachable, access switches behind it down Power cycle, console access, hardware swap
One floor/IDF Trunk link failure Access switches up but no VLAN connectivity Check trunk port, SFP, cable between access and dist
Devices up but no clients DHCP failure Clients getting APIPA addresses Check DHCP server, ip helper-address, DHCP relay
Devices up, wireless clients down WLC issue APs reachable but no SSID broadcast Check WLC status, AP join status
Devices up, some clients down VLAN issue Specific VLAN clients affected Check VLAN trunking, SVI status

Issue 5: Wireless Client Roaming Issues

Trigger: Wireless users report drops when moving between floors or areas, or CatC shows poor wireless health scores.

Step 1: Get Client History

# Extended time range to capture roaming events
CCC_HOST=$CCC_HOST CCC_USER=$CCC_USER CCC_PWD=$CCC_PWD python3 $MCP_CALL "python3 -u $CATC_MCP_SCRIPT" get_api_compatible_time_range '{"time_window":"last 8 hours"}'

# Get detailed client info with wireless views
CCC_HOST=$CCC_HOST CCC_USER=$CCC_USER CCC_PWD=$CCC_PWD python3 $MCP_CALL "python3 -u $CATC_MCP_SCRIPT" get_client_details_by_mac '{"client_mac_address":"AA:BB:CC:DD:EE:FF","start_time":1705312800000,"end_time":1705399200000,"view":["Wireless","WirelessHealth"]}'

Step 2: Analyze Roaming Indicators

Look for:

  • AP changes -- Frequent AP name changes indicate roaming events
  • RSSI drops -- RSSI dipping below -70 dBm before roaming = sticky client (not roaming early enough)
  • Band changes -- Client flipping between 2.4 GHz and 5 GHz during movement
  • SSID consistency -- Client should stay on the same SSID during roaming

Step 3: Check AP Coverage at the Problem Area

# List all APs at the affected site
CCC_HOST=$CCC_HOST CCC_USER=$CCC_USER CCC_PWD=$CCC_PWD python3 $MCP_CALL "python3 -u $CATC_MCP_SCRIPT" fetch_devices '{"family":["Unified AP"],"locationName":["Global/USA/NYC/Floor3"]}'

# Count wireless clients per AP to find overloaded APs
CCC_HOST=$CCC_HOST CCC_USER=$CCC_USER CCC_PWD=$CCC_PWD python3 $MCP_CALL "python3 -u $CATC_MCP_SCRIPT" get_clients_list '{"start_time":1705312800000,"end_time":1705399200000,"client_type":"wireless","site_hierarchy":["Global/USA/NYC/Floor3"]}'

Roaming Issue Root Causes

Symptom Likely Cause Resolution
Client holds onto far AP (sticky client) 802.11k/v not enabled or client doesn't support it Enable Optimized Roaming, BSS Transition Management
Client drops during roam 802.11r (FT) not enabled, or PMK caching disabled Enable Fast Transition (FT), enable CCKM/PMK caching
Client roams to 2.4 GHz Band steering not aggressive enough Increase band steering threshold, check client capability
Dead zone between APs RF coverage gap Add AP, increase power (carefully), adjust antenna
Client bounces between 2 APs Equal signal from both APs Reduce power on one AP, adjust cell boundaries

Issue 6: Catalyst Center Collection or API Issues

Trigger: CatC data seems stale, APIs return unexpected errors, or collectionStatus shows failures across many devices.

Check Collection Failures

CCC_HOST=$CCC_HOST CCC_USER=$CCC_USER CCC_PWD=$CCC_PWD python3 $MCP_CALL "python3 -u $CATC_MCP_SCRIPT" fetch_devices '{"collectionStatus":["Partial Collection Failure"]}'

CCC_HOST=$CCC_HOST CCC_USER=$CCC_USER CCC_PWD=$CCC_PWD python3 $MCP_CALL "python3 -u $CATC_MCP_SCRIPT" fetch_devices '{"collectionStatus":["Could Not Synchronize"]}'

API Time Range Errors

If client API calls return error 14013 (start time > 30 days ago):

  • Always use get_api_compatible_time_range first to ensure the time range is valid
  • The tool automatically clamps start times to the 30-day boundary

If client API calls return error 14006 (data not ready for endTime):

  • The get_clients_list, get_client_details_by_mac, and get_clients_count tools automatically retry with the API-suggested adjusted endTime
  • This is normal behavior when querying very recent data (within the last few minutes)

Troubleshooting Report Format

Always produce a structured findings report after completing a troubleshooting session:

Troubleshooting Report
=======================
Catalyst Center: $CCC_HOST
Timestamp: YYYY-MM-DD HH:MM UTC
Ticket/Case: [reference number if applicable]

Problem Statement
-----------------
[What was reported, by whom, when it started]

Impact Assessment
-----------------
Devices affected: X unreachable out of Y total at site
Clients affected: ~Z clients (estimated from client count delta)
Sites affected: [list]
Severity: CRITICAL / HIGH / MEDIUM / LOW

Investigation Timeline
-----------------------
1. [HH:MM] Checked CatC device reachability -- found X devices unreachable
2. [HH:MM] Identified site-localized issue at Global/USA/NYC/Floor3
3. [HH:MM] Checked distribution switch DIST-SW-NYC -- reachable
4. [HH:MM] Found TenGig1/0/1 (uplink to Floor3 IDF) down/down
5. [HH:MM] pyATS logs show %LINK-3-UPDOWN at 14:23 UTC
6. [HH:MM] SFP transceiver showing rx power below threshold

Root Cause
----------
Failing SFP transceiver on DIST-SW-NYC TenGigabitEthernet1/0/1
(uplink to Floor3 access layer IDF)

Resolution
----------
[Steps taken to resolve, or escalation path if unresolved]

Verification
-----------
- All Floor3 access switches returned to Reachable in CatC
- Client count at Floor3 recovered to baseline (335 clients)
- No further interface flaps observed in 30-minute monitoring window

Preventive Measures
--------------------
- Schedule optical monitoring for all uplink SFPs
- Add redundant uplink to Floor3 IDF (single point of failure identified)

GAIT Audit Trail

After completing any troubleshooting session, record the findings and resolution in GAIT:

python3 $MCP_CALL "python3 -u $GAIT_MCP_SCRIPT" gait_record_turn '{"input":{"role":"assistant","content":"Troubleshooting: Site-wide outage at Global/USA/NYC/Floor3. Root cause: Failing SFP on DIST-SW-NYC Te1/0/1. Impact: 335 clients, 5 access switches unreachable for 47 minutes. Resolution: SFP replaced, services restored. Preventive: Redundant uplink recommended.","artifacts":[]}}'
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claude-code1
replit1
junie1
windsurf1
zencoder1