Enhanced linked mode allows vSphere administrators to seamlessly connect and manage multiple vCenter Server instances across data centers, regions, or hybrid clouds through a single user interface. If you‘re new to vSphere or manage a sprawling virtual infrastructure, understanding enhanced linked mode is key to streamlining day-to-day management.
In this beginner‘s guide, we‘ll cover what enhanced linked mode is, how it works under the hood, deployment best practices, step-by-step configuration details, use cases, and alternatives. Armed with this information, you‘ll be well on your way to simplifying unified management of distributed environments using VMware vSphere.
What is vCenter Enhanced Linked Mode?
VMware vCenter Server acts as the centralized management layer for vSphere environments. It allows admins to provision, monitor and manage ESXi hosts and virtual machines through a single pane of glass.
However, as infrastructure grows across multiple locations, managing separate vCenter servers can create visibility gaps and operational challenges.
This is where enhanced linked mode comes in — it federates connections between vCenter Servers to create a unified view and shared management capabilities across environments that use the same single sign-on domain.
Key benefits include:
- Single point of management for distributed infrastructure
- Consistent visibility into global inventories and configurations
- Shared identities, roles, licenses across vCenter instances
- No extra hardware needed for unified management
"93% of organizations have adopted multi-cloud strategies encompassing on-premises data centers, public clouds, and edge environments." – Flexera 2022 State of Cloud Report
Now that you understand the basics, let‘s explore under the hood to see how enhanced linking works across vCenter Servers.
Understanding the Enhanced Linked Mode Architecture
The core components that enable enhanced linked mode are:
- Platform Services Controller (PSC): Centralized authentication and management across vCenter services.
- vCenter Server: Management, provisioning, and visibility into vSphere environments.
- Single Sign-On Domain: Allows unified identities and authentication across vSphere services.
In a linked environment, each vCenter Server connects to a local embedded PSC during deployment. The PSCs handle identity management through an integrated Single Sign-On domain that spans all linked vCenter instances.
This architecture allows vCenter services to communicate securely to provide a global view and shared management plane:
- Common access and roles — Log in once to see and manage all infrastructure
- Unified inventory view — Combined view showing all objects and relationships
- Shared tagging — Assign tags that persist across the environment
- Cross-vCenter workload migration — Live migrate VMs between locations
The diagram below summarizes the enhanced linked mode architecture with embedded PSCs:
Image source: GeekFlare
Now that you know how enhanced linked mode unites vSphere management silos, let‘s go over some key planning decisions for deployment.
Deploying vCenter Server with Enhanced Linked Mode
Before implementation, here are some vCenter enhanced linked mode design choices to consider:
1. Platform Services Controller Topology
You can deploy the PSC embedded with each vCenter Server, or use an external “shared” PSC to serve multiple vCenter instances.
Each approach has tradeoffs to weigh:
- Embedded: Simplifies deployment and lifecycle management of vCenter. Limit of 10 linked vCenter Servers.
- External: Allows >10 linked vCenters. Additional high availability options
For most enhanced linked mode deployments, using the embedded PSC approach streamlines configuration while providing robust unified management.
2. vCenter Topology and High Availability
Choose whether to install vCenter on Windows or as a vCenter Server Appliance (VCSA). Also determine if local high availability is required for each vCenter.
Key options:
- VCSA makes setup easier and boosts portability. vCenter HA lets you run active-passive VCSAs in enhanced linked mode to remove vCenter as a single point of failure.
- Windows-based vCenter allows customization. Can cluster using Windows failover clustering for HA.
The VCSA paired with vCenter HA provides a streamlined option that keeps your environment available.
3. Networking and Connectivity
Since enhanced linked mode connects vCenter Servers across locations, sufficient LAN/WAN connectivity is crucial for unified management.
Consider:
- Low latency connectivity for cross-site live migration, and vCenter communication
- Sufficient bandwidth to sync large inventories across vCenters
- Open required ports on firewalls between sites
Common Enhanced Linked Mode Ports & Protocols
| Source | Target | Port | Protocol | Purpose |
|---|---|---|---|---|
| vCenter | vCenter | 443 | TCP | Cross-vCenter communication |
| VCSA/PSC | Other PSC | 443 | TCP | SSO & identity replication |
| ESXi | vCenter | 443 | TCP | Management traffic |
| Remote clients | vCenter | 443 | TCP | vSphere client access |
With the design decisions made, let‘s walk through the deployment process.
Step-by-Step Guide: Deploying Enhanced Linked Mode
Follow this playbook to set up enhanced linked mode across vCenter servers:
Deploy First vCenter Server Appliance
- Boot the VCSA .ISO on your intended vCenter host
- Open vSphere Client and connect to your ESXi host
- Right-click host and select “Deploy OVF Template”
- Follow the Deploy OVF Template wizard to install VCSA
- Power on the VCSA once deployed and open the vSphere Web Client
- Configure settings like SSO credentials and vCenter network connectivity
- Record the SSO domain name for linking additional vCenters
Join Additional vCenter Servers into Linked Mode
For each new vCenter:
- Mount and boot the VCSA .ISO
- Launch vCenter installer UI
- Select “Join existing SSO domain” and enter:
- SSO domain
- SSO admin credentials
- Primary vCenter hostname
- Complete the installation wizard to link the new VCSA
- Login to vSphere Client to verify unified inventory across vCenters
Repeat to link additional vCenter Servers into the shared SSO domain.
Managing Enhanced Linked Mode Environments
Once up and running, enhanced linked mode unlocks powerful unified management capabilities:
- Global permissions & roles — Centrally define access controls applied across all vCenters
- Cross-site migration — Live migrate VMs using shared datastores in the global inventory
- Unified monitoring & tagging — Apply tags and see alerts across environments
- Simplified backup & DR — Automate backups across entire linked environment
Some best practices for operating in enhanced linked mode:
- Carefully manage permissions and roles — Broad access could lead to unintended changes
- Monitor network usage between sites — Ensure sufficient connectivity as inventories scale
- Test failover procedures — Validate availability of vCenter HA or alternative vCenters if one instance becomes unavailable
Adopting these recommendations will optimize reliability and security as your unified landscape expands.
Comparing Standard vs Enterprise vCenter for Enhanced Linked Mode
The capabilities available through enhanced linked mode depend on the vCenter edition deployed in your environment:
vCenter Standard
- Unified inventory view
- Shared identity management
- Cross-vCenter consistency for roles and permissions
- Tagging across vCenters
- Multi-site monitoring
vCenter Enterprise
Includes all standard features, plus:
- Workload migration across sites
- Linked mode support > 10 vCenters
- Automated load balancing
- Proactive HA for vCenter
- Deep integration with NSX-T
For large multi-region environments, investing in the Enterprise license unlocks cross-site mobility and true global management unification.
Troubleshooting Common Enhanced Linked Mode Problems
Issues sometimes arise when deploying or operating unified linked environments. Some common enhanced linked mode problems include:
Lost vCenter Connectivity
- Check network connectivity between vCenter Servers and PSCs across sites. Reference the port table above and verify firewall rules.
SSO Authentication Failures
- Ensure all vCenters use the same SSO domain configuration. Resolve any mismatch in credentials or configuration.
SSO Replication Failure
- Validate forward and reverse DNS resolution for all vCenters and PSCs. Rebuild SSO replication topology if host information mismatches.
Limited Inventory Visibility
- Confirm vCenter licenses support the enhanced linked mode features needed based on standard vs enterprise comparison.
Knowing potential pitfall areas will help admins quickly remediate and restore full unified functionality when issues pop up.
Real-World Use Cases
Here are examples of how major companies leverage VMware enhanced linked mode across their hybrid infrastructure:
Global Financial Institutions
- Manage trading platform infrastructure across on-prem data centers and public clouds
- Unified visibility and control over 1000s of virtual machines globally
- Seamlessly shift workloads based on cost, compliance and latency needs
Multi-National Retailers
- Bridge regional stores, warehouses, and cloud resources
- Centralized dashboard for inventory, point-of-sale, and operations systems
- Cross-cloud workload migration for seasonal capacity expansion
Technology & Telecom Providers
- Reduce network backbone complexity after mergers and acquisitions
- Combined management for consumer mobile, ISP, and entertainment services
- Flexibly scale products and capacity across geography and centers
In each case, enhanced linked mode was a pivotal technology for tying together federated environments as businesses grew and infrastructure complexity mounted.
The Bottom Line
Like a “master key” for sprawling vSphere deployments, enhanced linked mode unlocks simplified centralized management otherwise impossible across disconnected vCenter Servers.
By bridging gaps between locations through shared identity, inventory, and control plane, it eliminates major visibility and management pain points. The result is globally optimized infrastructure monitoring, efficiency, and agility at scale.
As multi-site and hybrid cloud architectures become the norm, enhanced linked mode will only grow in strategic value for VMware administrators through easier cross-environment insight and automation.
