VxRail Stretched Cluster
Requirements
In an environment with multiple
availability zones, Layer 2 networks must be stretched between the availability zones by the
physical infrastructure. You also must provide a Layer 3 gateway that is highly available
between availability zones. The method for stretching these Layer 2 networks and providing a
highly available Layer 3 gateway is vendor-specific.
VLANs and Subnets for Multiple
Available Zones
This section displays a sample configuration
for an environment with multiple availability zones. The management, Uplink 01,
Uplink 02, and Edge Overlay networks in each availability zone must be stretched to
facilitate failover of the NSX-T Edge appliances between availability zones. The
Layer 3 gateway for the management and Edge Overlay networks must be highly
available across the availability zones.
The management network VLAN can
be the same for the management domain and VI workload domains, although the
table below shows an example where these VLANs are different (1611 vs
1631).
Function | Availability Zone
1 | Availability Zone
2 | VLAN ID | IP Range | HA Layer 3
Gateway | Recommended MTU |
|---|---|---|---|---|---|---|
Management (AZ1 and AZ2) | ✓ | ✓ | 1611
(Stretched) | 172.16.11.0/24 | ✓ | 1500 |
vSphere
vMotion | ✓ | X | 1612 | 172.16.12.0/24 | ✓ | 9000 |
vSAN | ✓ | X | 1613 | 172.16.13.0/24 | ✓ | 9000 |
NSX-T Host
Overlay | ✓ | X | 1614 | 172.16.14.0/24 | ✓ | 9000 |
NSX-T Edge
Uplink01 | ✓ | ✓ | 2711
(Stretched) | 172.27.11.0/24 | X | 9000 |
NSX-T Edge
Uplink02 | ✓ | ✓ | 2712
(Stretched) | 172.27.12.0/24 | X | 9000 |
NSX-T Edge
Overlay | ✓ | ✓ | 2713
(Stretched) | 172.27.13.0/24 | ✓ | 9000 |
vSphere
vMotion | X | ✓ | 1622 | 172.16.22.0/24 | ✓ | 9000 |
vSAN | X | ✓ | 1623 | 172.16.23.0/24 | ✓ | 9000 |
Host Overlay | X | ✓ | 1624 | 172.16.24.0/24 | ✓ | 9000 |
If a VLAN is stretched between AZ1
and AZ2, then the data center needs to provide appropriate routing and failover of
the gateway for that network.
Function | Availability Zone
1 | Availability Zone
2 | VLAN ID | IP Range | HA Layer 3
Gateway | |
|---|---|---|---|---|---|---|
Management (AZ1 and AZ2) | ✓ | ✓ | 1631 | 172.16.31.0/24 | ✓ | |
vSphere vMotion | ✓ | X | 1632 | 172.16.32.0/24 | ✓ | |
vSAN | ✓ | X | 1633 | 172.16.33.0/24 | ✓ | |
Host Overlay | ✓ | X | 1634 | 172.16.34.0/24 | ✓ | |
vSphere vMotion | X | ✓ | 2732 | 172.27.32.0/24 | ✓ | |
vSAN | X | ✓ | 2733 | 172.16.33.0/24 | ✓ | |
Host Overlay | X | ✓ | 1621 | 172.16.21.0/24 | ✓ |
Networking for Multiple
Availability Zones
There are specific physical data
center network requirements for a topology with multiple availability zones.
Component | Requirement |
|---|---|
MTU |
|
Layer 3 gateway
availability | For VLANs that are stretched between
available zones, configure data center provided method, for
example, VRRP or HSRP, to failover the Layer 3 gateway between
availability zones. |
DHCP
availability | For VLANs that are stretched between
availability zones, provide high availability for the DHCP
server so that a failover operation of a single availability
zone will not impact DHCP availability. You cannot
stretch a cluster that uses static IP addresses for the
NSX-T Host Overlay Network TEPs. |
BGP routing | Each availability
zone data center must have its own Autonomous System Number
(ASN). |
Ingress and egress
traffic |
|
Latency |
|