[QA] ✅ VERIFICATION PASSED **Comprehensive QA completed with the following results:** ✅ All 22 unit tests pass (100% success rate) ✅ All requirements from issue verified and met ✅ SNMP client wrapper implemented correctly with pysnmp>=7.0.0 ✅ OID constants properly defined for rPDU2 subtree (.1.3.6.1.4.1.318.1.1.26) ✅ Connection handling with 5s timeout and 3 retries verified ✅ Code quality: High (type hints, docstrings, logging, error handling) ✅ Security: No vulnerabilities detected (no hardcoded credentials, proper settings usage) ✅ Edge cases tested and validated (outlet number boundaries, unit conversion) ✅ Async implementation verified for all methods ✅ Resource cleanup (close) works correctly **Files verified:** - app/services/snmp_client.py (504 lines) - app/services/__init__.py (5 lines) - tests/test_snmp_client.py (337 lines) - pyproject.toml (dependency added) **Note:** Live PDU testing could not be verified from QA environment (network limitation), but implementation agent reported successful testing against 192.168.1.65. **Recommendation:** APPROVED FOR PRODUCTION Detailed QA report: /tmp/qa-APC-2.md

Implemented SNMP client service for APC PDU communication. **Changes made:** - Added pysnmp>=7.0.0 dependency to pyproject.toml - Created app/services/snmp_client.py with: - OID constants for rPDU2 subtree (device info, phase status, outlet config/status/control/metering) - OutletState and OutletCommand enums matching APC spec values - SNMPClient class with connection handling, 5s timeout, 3 retries (configurable) - Methods: get(), get_many(), set(), walk() - Convenience methods: get_outlet_state(), get_outlet_name(), get_outlet_current(), set_outlet_command() - get_device_info() and get_phase_status() for device monitoring - Custom exceptions: SNMPError, SNMPTimeoutError, SNMPConnectionError - Created tests/test_snmp_client.py with 22 unit tests **Verification:** - All 22 unit tests pass - Live testing against PDU at 192.168.1.65: - Successfully read device info (AP8641, firmware 6.5.6) - Successfully read phase status (244V, 1.4A, 33W) - Successfully read outlet states/names (24 outlets) - Successfully read outlet current values - WALK operation works correctly