Pyats Parallel Ops

Parallel Fleet Operations

When to Use

• Fleet-wide health checks across all devices in the testbed
• Mass configuration audits (collect running configs from every device)
• Network-wide routing table snapshots for baseline or comparison
• Pre/post change validation across all affected devices simultaneously
• Any operation where running sequentially on 10+ devices would be too slow

How pCall Works in OpenClaw

In OpenClaw, parallel execution (pCall) is achieved by listing multiple exec commands in a single response. The agent runtime dispatches them concurrently and collects all results before proceeding.

Key Principles

1. Group by role or site -- Organize devices into logical groups (core, distribution, access, WAN, DC) before dispatching
2. Run operations concurrently -- List one MCP call per device; they execute in parallel
3. Failure isolation -- If one device times out or errors, the other results are still collected
4. Result aggregation -- Collect all results, then produce a unified fleet report
5. Severity sorting -- Sort findings from CRITICAL to HEALTHY so the worst problems surface first

pCall Pattern

To run the same command on multiple devices in parallel, list the calls together:

# Device 1
PYATS_TESTBED_PATH=$PYATS_TESTBED_PATH python3 $MCP_CALL "${PYATS_PYTHON:-python3} -u $PYATS_MCP_SCRIPT" pyats_run_show_command '{"device_name":"R1","command":"show version"}'

# Device 2
PYATS_TESTBED_PATH=$PYATS_TESTBED_PATH python3 $MCP_CALL "${PYATS_PYTHON:-python3} -u $PYATS_MCP_SCRIPT" pyats_run_show_command '{"device_name":"R2","command":"show version"}'

# Device 3
PYATS_TESTBED_PATH=$PYATS_TESTBED_PATH python3 $MCP_CALL "${PYATS_PYTHON:-python3} -u $PYATS_MCP_SCRIPT" pyats_run_show_command '{"device_name":"SW1","command":"show version"}'

All three commands execute concurrently. Results arrive independently and are aggregated by the agent.

Step 0: Discover the Fleet

Always start by listing all devices in the testbed so you know what to operate on:

PYATS_TESTBED_PATH=$PYATS_TESTBED_PATH python3 $MCP_CALL "${PYATS_PYTHON:-python3} -u $PYATS_MCP_SCRIPT" pyats_list_devices '{}'

This returns every device with its name, platform, OS, and connection details. Use this to build the device list for parallel operations.

Example 1: Fleet-Wide Health Check

Run a health check on all devices in the testbed concurrently.

Phase 1: Parallel Data Collection

Issue these commands simultaneously -- one set per device:

# R1 - CPU and memory
PYATS_TESTBED_PATH=$PYATS_TESTBED_PATH python3 $MCP_CALL "${PYATS_PYTHON:-python3} -u $PYATS_MCP_SCRIPT" pyats_run_show_command '{"device_name":"R1","command":"show processes cpu sorted"}'

# R2 - CPU and memory
PYATS_TESTBED_PATH=$PYATS_TESTBED_PATH python3 $MCP_CALL "${PYATS_PYTHON:-python3} -u $PYATS_MCP_SCRIPT" pyats_run_show_command '{"device_name":"R2","command":"show processes cpu sorted"}'

# SW1 - CPU and memory
PYATS_TESTBED_PATH=$PYATS_TESTBED_PATH python3 $MCP_CALL "${PYATS_PYTHON:-python3} -u $PYATS_MCP_SCRIPT" pyats_run_show_command '{"device_name":"SW1","command":"show processes cpu sorted"}'

Then in a second parallel wave, collect interface and NTP status:

# R1 - Interfaces
PYATS_TESTBED_PATH=$PYATS_TESTBED_PATH python3 $MCP_CALL "${PYATS_PYTHON:-python3} -u $PYATS_MCP_SCRIPT" pyats_run_show_command '{"device_name":"R1","command":"show ip interface brief"}'

# R2 - Interfaces
PYATS_TESTBED_PATH=$PYATS_TESTBED_PATH python3 $MCP_CALL "${PYATS_PYTHON:-python3} -u $PYATS_MCP_SCRIPT" pyats_run_show_command '{"device_name":"R2","command":"show ip interface brief"}'

# SW1 - Interfaces
PYATS_TESTBED_PATH=$PYATS_TESTBED_PATH python3 $MCP_CALL "${PYATS_PYTHON:-python3} -u $PYATS_MCP_SCRIPT" pyats_run_show_command '{"device_name":"SW1","command":"show ip interface brief"}'

Phase 2: Parallel Log Collection

# R1 - Logs
PYATS_TESTBED_PATH=$PYATS_TESTBED_PATH python3 $MCP_CALL "${PYATS_PYTHON:-python3} -u $PYATS_MCP_SCRIPT" pyats_show_logging '{"device_name":"R1"}'

# R2 - Logs
PYATS_TESTBED_PATH=$PYATS_TESTBED_PATH python3 $MCP_CALL "${PYATS_PYTHON:-python3} -u $PYATS_MCP_SCRIPT" pyats_show_logging '{"device_name":"R2"}'

# SW1 - Logs
PYATS_TESTBED_PATH=$PYATS_TESTBED_PATH python3 $MCP_CALL "${PYATS_PYTHON:-python3} -u $PYATS_MCP_SCRIPT" pyats_show_logging '{"device_name":"SW1"}'

Phase 3: Aggregate and Report

After all parallel results return, analyze each device individually and produce the fleet summary (see Fleet Report Format below).

Example 2: Fleet-Wide Config Audit

Collect the running configuration from every device in parallel for compliance analysis.

# R1 - Running config
PYATS_TESTBED_PATH=$PYATS_TESTBED_PATH python3 $MCP_CALL "${PYATS_PYTHON:-python3} -u $PYATS_MCP_SCRIPT" pyats_show_running_config '{"device_name":"R1"}'

# R2 - Running config
PYATS_TESTBED_PATH=$PYATS_TESTBED_PATH python3 $MCP_CALL "${PYATS_PYTHON:-python3} -u $PYATS_MCP_SCRIPT" pyats_show_running_config '{"device_name":"R2"}'

# SW1 - Running config
PYATS_TESTBED_PATH=$PYATS_TESTBED_PATH python3 $MCP_CALL "${PYATS_PYTHON:-python3} -u $PYATS_MCP_SCRIPT" pyats_show_running_config '{"device_name":"SW1"}'

# SW2 - Running config
PYATS_TESTBED_PATH=$PYATS_TESTBED_PATH python3 $MCP_CALL "${PYATS_PYTHON:-python3} -u $PYATS_MCP_SCRIPT" pyats_show_running_config '{"device_name":"SW2"}'

After collection, apply the pyats-security audit checks to each config and produce a fleet-wide security posture report.

Common config audit checks to apply in parallel:

• SSH version 2 only
• No telnet on VTY lines
• service password-encryption enabled
• VTY access-class applied
• NTP configured
• Logging host configured
• No default SNMP community strings

Example 3: Fleet-Wide Routing Table Snapshot

Capture the routing table from every device simultaneously for baseline documentation or pre-change verification.

# R1 - Full routing table
PYATS_TESTBED_PATH=$PYATS_TESTBED_PATH python3 $MCP_CALL "${PYATS_PYTHON:-python3} -u $PYATS_MCP_SCRIPT" pyats_run_show_command '{"device_name":"R1","command":"show ip route"}'

# R2 - Full routing table
PYATS_TESTBED_PATH=$PYATS_TESTBED_PATH python3 $MCP_CALL "${PYATS_PYTHON:-python3} -u $PYATS_MCP_SCRIPT" pyats_run_show_command '{"device_name":"R2","command":"show ip route"}'

# R3 - Full routing table
PYATS_TESTBED_PATH=$PYATS_TESTBED_PATH python3 $MCP_CALL "${PYATS_PYTHON:-python3} -u $PYATS_MCP_SCRIPT" pyats_run_show_command '{"device_name":"R3","command":"show ip route"}'

# R4 - Full routing table
PYATS_TESTBED_PATH=$PYATS_TESTBED_PATH python3 $MCP_CALL "${PYATS_PYTHON:-python3} -u $PYATS_MCP_SCRIPT" pyats_run_show_command '{"device_name":"R4","command":"show ip route"}'

After collection, analyze per device:

• Total route count by protocol (connected, static, OSPF, BGP, EIGRP)
• Default route presence and source
• Expected prefix verification
• ECMP paths for critical prefixes

Produce a fleet routing summary:

Fleet Routing Snapshot - YYYY-MM-DD HH:MM UTC

┌──────────┬────────┬────────┬──────┬──────┬──────────────┬─────────┐
│ Device   │ Total  │ Conn.  │ OSPF │ BGP  │ Default Rte  │ Status  │
├──────────┼────────┼────────┼──────┼──────┼──────────────┼─────────┤
│ R1       │ 47     │ 5      │ 12   │ 28   │ via 10.1.1.2 │ HEALTHY │
│ R2       │ 45     │ 4      │ 12   │ 27   │ via 10.1.1.1 │ HEALTHY │
│ R3       │ 38     │ 3      │ 12   │ 21   │ via 10.2.1.1 │ WARNING │
│ R4       │ 0      │ 0      │ 0    │ 0    │ MISSING      │ CRITICAL│
└──────────┴────────┴────────┴──────┴──────┴──────────────┴─────────┘

Example 4: Severity-Sorted Fleet Reporting

After collecting results from all devices, aggregate findings and sort by severity. This is the standard output format for all fleet operations.

Severity Levels

1. CRITICAL -- Immediate action required. Device unreachable, process crash, zero routes, total connectivity loss.
2. HIGH -- Fix within hours. CPU > 90%, memory > 95%, routing adjacency down, interface flapping.
3. MEDIUM -- Fix within days. Missing NTP, elevated CPU (50-75%), log errors, config non-compliance.
4. HEALTHY -- No issues. All checks passed.

Fleet Report Format

Fleet Health Report - YYYY-MM-DD HH:MM UTC
Testbed: production-network
Devices scanned: 8 | Duration: 12s (parallel)

=== CRITICAL (Immediate Action) ===

[C-001] R4 - UNREACHABLE
  Connection timed out after 30s. Verify device is powered on and management IP is reachable.
  Impact: No data collected for R4. Manual investigation required.

[C-002] SW2 - CPU 97% (5min avg)
  Top process: OSPF-1 Hello (45%), IP Input (32%)
  Impact: Risk of control plane failure. OSPF hellos may be missed.

=== HIGH (Fix Within Hours) ===

[H-001] R2 - GigabitEthernet3 down/down
  Last state change: 2 hours ago. 47 resets in last 24h.
  Impact: Backup WAN link unavailable. No redundancy for site B.

[H-002] SW1 - OSPF neighbor 3.3.3.3 in INIT state
  Expected: FULL. Interface: Vlan100. Duration: 45 minutes.
  Impact: Inter-VLAN routing for VLAN 100 may be impaired.

=== MEDIUM (Fix Within Days) ===

[M-001] R1 - NTP not synchronized
  No peer with '*' in show ntp associations. Clock offset: unknown.
  Impact: Log timestamps may be inaccurate for forensics.

[M-002] R3 - 3 OSPF adjacency flaps in last 24h
  Neighbors affected: 2.2.2.2 on Gi1 (flapped 3 times).
  Impact: Route convergence events. Brief traffic disruption during SPF.

=== HEALTHY ===

R1: All checks passed (CPU 12%, Mem 45%, 4/4 interfaces up, OSPF stable)
R3: All checks passed (CPU 8%, Mem 38%, 3/3 interfaces up, BGP stable)
SW3: All checks passed (CPU 5%, Mem 22%, 24/24 ports up, STP stable)

=== FLEET SUMMARY ===

┌──────────┬──────────┬──────────────────────────────────────────────┐
│ Device   │ Status   │ Key Finding                                  │
├──────────┼──────────┼──────────────────────────────────────────────┤
│ R4       │ CRITICAL │ Unreachable - connection timeout              │
│ SW2      │ CRITICAL │ CPU 97% - OSPF/IP Input                      │
│ R2       │ HIGH     │ Gi3 down/down - 47 resets                    │
│ SW1      │ HIGH     │ OSPF neighbor INIT - Vlan100                 │
│ R1       │ MEDIUM   │ NTP not synchronized                         │
│ R3       │ MEDIUM   │ 3 OSPF flaps in 24h                          │
│ R1       │ HEALTHY  │ All checks passed                            │
│ R3       │ HEALTHY  │ All checks passed                            │
│ SW3      │ HEALTHY  │ All checks passed                            │
└──────────┴──────────┴──────────────────────────────────────────────┘

Overall Fleet Status: CRITICAL (2 critical, 2 high, 2 medium, 3 healthy)

Failure Isolation

When one device fails during parallel execution, it does not block or cancel the other operations:

• Connection timeout -- Mark device as CRITICAL/UNREACHABLE, continue with others
• Command error -- Record the error for that device, continue collecting from others
• Parse failure -- Fall back to raw text output for that device, report as WARNING

Handling Unreachable Devices

# If R4 times out, you still get results from R1, R2, R3
# In the fleet report, R4 appears as:
#   [C-001] R4 - UNREACHABLE
#   Connection timed out. Device excluded from further checks.

The key principle: always produce a report for every device, even if the report says "unreachable."

Grouping Strategies

By Role

Group devices by their function in the network to prioritize operations:

Core routers:    R1, R2          (check first - highest blast radius)
Distribution:    SW1, SW2        (check second)
Access:          SW3, SW4, SW5   (check third)
WAN:             WAN1, WAN2      (check in parallel with core)

By Site

For multi-site networks, group by location:

Site A (HQ):      R1, SW1, SW2
Site B (Branch):  R2, SW3
Site C (DR):      R3, SW4

By Change Scope

When validating a change, group by affected vs unaffected:

Affected devices:    R1, R2       (check thoroughly - full health check)
Adjacent devices:    SW1, R3      (check routing adjacencies and connectivity)
Unaffected devices:  SW3, SW4     (spot check - verify no collateral damage)

Scaling Guidelines

For large fleets, start with a sampling strategy: pick 2-3 devices per role per site, run full health checks, then expand to the full fleet only if anomalies are found.

Integration with Other Skills

• pyats-health-check -- The single-device health check procedure. pCall scales it to the fleet by issuing one health check per device in parallel.
• pyats-security -- Fleet-wide security audit. Collect all running configs in parallel, then apply security checks to each config.
• pyats-topology -- Fleet-wide topology discovery. Run CDP/LLDP neighbor collection on all devices in parallel to build the complete network map.
• pyats-dynamic-test -- Run the same aetest validation script against multiple devices in parallel for fleet-wide compliance testing.
• pyats-config-mgmt -- Pre/post change validation on all affected devices simultaneously.
• drawio-diagram -- After fleet discovery, generate a topology diagram showing device status (color-coded by health severity).
• markmap-viz -- Generate fleet health mind maps organized by severity or site.