IT Infrastructure Migration: Comprehensive guide

Comprehensive guide for IT infrastructure migration, specifically tailored for migrating firewalls, routers, switches, load balancers (F5), Cisco ISE, Wireless LAN Controllers (WLC), and IDS/IPS appliances. The guide ensures a realistic, accurate, and systematic approach to follow during your migration project.

Step 1: Define the Scope of Migration

• Understand Migration Objectives:
  • Examples: Upgrading hardware, moving to a new data center, or improving performance/security.
  • Define success criteria (e.g., zero downtime for critical services, improved latency, enhanced security).
• Identify Systems to Migrate:
  • List all network devices (firewalls, routers, switches, etc.) and their roles in the existing infrastructure.
• Determine Migration Type:
  • Lift-and-Shift: Move existing configurations to new devices.
  • Rebuild and Optimize: Redesign configurations for enhanced performance/security.

Step 2: Assess Current Infrastructure

• Network Audit:
  • Document existing configurations, IP addressing schemes, routing protocols, VLANs, and policies.
  • Capture all current rules, such as firewall policies, NAT rules, and ACLs.
• Inventory Devices:
  • Record device models, firmware versions, and licenses.
  • Identify end-of-life (EoL) or end-of-support (EoS) devices for replacement.
• Dependencies:
  • Map interdependencies between devices and applications.

Step 3: Develop a Migration Plan

• Define Migration Phases:
  • Break the project into manageable phases, such as pre-migration, migration, and post-migration.
• Create a Rollback Plan:
  • Develop rollback strategies for each migration step to revert to the previous setup if issues arise.
• Plan Downtime:
  • Schedule maintenance windows, especially for services that require disruption.
• Backup Configurations:
  • Take complete backups of all device configurations before starting.

Step 4: Pre-Migration Preparation

General Preparation:

1. Staging Environment:
   • Set up a test environment to replicate the production network.
   • Validate configurations and test device performance.
2. Firmware Updates:
   • Upgrade firmware/software on new devices to the latest stable version.
3. License Activation:
   • Activate licenses for appliances like F5, Cisco ISE, or IDS/IPS.

Device-Specific Tasks:

1. Firewalls:
   • Export all security policies, NAT rules, and VPN configurations.
   • Map security zones for migration.
2. Routers:
   • Document routing tables, static routes, and dynamic routing protocols (e.g., OSPF, BGP).
3. Switches:
   • Export VLAN configurations and port mappings.
   • Identify trunk and access ports.
4. Load Balancer (F5):
   • Export virtual server, pool, and SSL configurations.
   • Map backend servers and health monitoring settings.
5. Cisco ISE:
   • Export authentication/authorization policies and user profiles.
   • List integrations with Active Directory, WLCs, and switches.
6. WLC:
   • Backup SSIDs, VLAN mappings, and RF profiles.
   • Ensure access points (APs) are registered.
7. IDS/IPS:
   • Export detection/prevention rules and logging configurations.
   • Plan integration with SIEM tools for centralized monitoring.

Step 5: Perform Migration

Step-by-Step Execution

1. Firewalls:
   • Deploy the new firewall in parallel to the existing one (if possible).
   • Configure security zones, access rules, NAT, and VPNs on the new device.
   • Test connectivity for each zone and verify traffic inspection rules.
   • Gradually migrate traffic to the new firewall.
2. Routers:
   • Configure static routes and enable routing protocols (OSPF/BGP) on the new router.
   • Establish adjacency with other routers and verify route propagation.
   • Test routing and failover scenarios.
3. Switches:
   • Migrate VLAN and trunk configurations to the new switch.
   • Connect access devices and test port-level configurations.
   • Verify loop prevention (STP/RSTP) and QoS settings.
4. Load Balancer (F5):
   • Configure virtual servers, pools, and SSL profiles on the new F5 device.
   • Add backend servers and test health monitoring.
   • Test traffic distribution and SSL offloading.
   • Migrate production traffic to the new load balancer.
5. Cisco ISE:
   • Integrate Cisco ISE with Active Directory and network devices (switches, WLCs).
   • Configure AAA policies for wired, wireless, and BYOD users.
   • Test 802.1X authentication and fallback mechanisms (e.g., MAB).
   • Gradually enforce policies on production traffic.
6. WLC:
   • Register access points with the new WLC.
   • Configure SSIDs, VLAN mappings, and RF profiles.
   • Test seamless roaming and guest access.
   • Migrate production wireless traffic to the new WLC.
7. IDS/IPS:
   • Deploy in inline mode (for active prevention) or passive mode (for monitoring).
   • Apply detection/prevention rules and enable logging.
   • Test against simulated threats to validate functionality.
   • Gradually route production traffic through the IDS/IPS.

Step 6: Post-Migration Validation

• Connectivity Testing:
  • Verify end-to-end connectivity using tools like ping, traceroute, and packet captures (Wireshark).
• Policy Validation:
  • Test firewall rules, routing protocols, and ISE policies for correctness.
• Traffic Monitoring:
  • Monitor traffic flows through the load balancer, firewall, and IDS/IPS.
• Wireless Performance:
  • Validate wireless connectivity, roaming, and signal strength.
• Failover Testing:
  • Simulate failover scenarios for HA devices (firewalls, load balancers, routers).

Step 7: Monitoring and Optimization

• Real-Time Monitoring:
  • Use monitoring tools like SolarWinds, Cisco Prime, or F5 BIG-IQ to track device health.
• Log Analysis:
  • Analyze logs for anomalies, dropped packets, or unauthorized access attempts.
• Fine-Tuning:
  • Optimize configurations based on performance data and user feedback.

Step 8: Documentation and Handover

• Update Network Diagrams:
  • Reflect the new topology and device placements.
• Configuration Documentation:
  • Save final configurations for all devices.
• Handover Documents:
  • Share detailed guides and SOPs for managing the new setup.
• Training:
  • Train the client’s team on managing and troubleshooting the new infrastructure.

Step 9: Maintenance and Scaling

• Scheduled Maintenance:
  • Plan regular firmware updates and security patches.
• Performance Audits:
  • Conduct periodic audits to ensure optimal performance.
• Capacity Planning:
  • Plan for future growth in traffic or user base.

This step-by-step migration plan ensures minimal disruption and a smooth transition to the new infrastructure. Let me know if you need templates for device configurations or testing checklists!