Migrated VMs keep their IP and MAC addresses because this VCF Operations HCX service bridges their networks (VLAN-tagged distributed port groups, NSX segments or NSX VPC subnets) to the remote site through a pair of appliances. Unless Mobility Optimized Networking is used, the default gateway stays at the source.
Also called HCX-NE.
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Terms in this definition
- Virtual machines
Infrastructure-as-a-service compute giving complete control of the operating system, making it a fit for lift-and-shift moves and for software relying on OS-level pieces like COM.
- VCF Operations HCX
Add-on licensed for moving workloads inside and between VCF private clouds and linking those environments, offering bulk or live migration plus network extension so IP addresses can stay the same.
- NSX
Software that handles networking and security across VCF, covering firewalling, load balancing, NAT, VPCs, overlay segments and Tier-0/1 gateways.
- NSX VPC
Isolated network space users run self-service under an NSX project, with dedicated subnets, security rules and built-in IPAM; a further tenancy tier.
- LSDOU
The sequence in which Group Policy is processed: the local policy first, followed by site, domain and organisational unit policies. The nearest, last-processed setting takes effect unless Enforced or Block Inheritance alters that.
- Mobility Optimized Networking
Avoids tromboning on networks extended by HCX: migrated VMs route via the destination site instead of back through the gateway at the source. This Network Extension option applies automatically to VMs moved by Bulk migration, whereas vMotion and RAV leave VMs on the source gateway until someone reconfigures them.
Related terms
- Destination site
Receives VMs and networks extended from its VCF Operations HCX partner. Because pairing works in one direction, any operation (service mesh, network extension, migration, or even moving VMs back) is initiated at the source end.
- HCX Manager
The appliance that manages VCF Operations HCX. One is deployed at each end of a migration from a single OVA image (sized by default at 4 vCPUs, 12 GB of RAM and a 60 GB disk), the pair is linked through site pairing, and a service mesh then rolls out the interconnect, network extension and related service appliances.
- MSS
Maximum segment size. Clamping this TCP value avoids fragmentation in tunnels like HCX Network Extension and NSX IPsec VPNs and lets NSX Federation carry cross-domain traffic over any MTU; the value is the largest single-segment payload a host will accept, worked out from the egress MTU.
- Network Extension HA
Resilience for HCX extended networks: two Network Extension appliances at each of two sites make an Active/Standby group that copes with losing any single appliance. Its status reads HEALTHY, DEGRADED, FAILINGOVER, FAILED or MAINTENANCE.
- Network Extension High Availability
Four Network Extension appliances, arranged across the two sites as an active pair and a standby pair, so that an extended network survives one appliance failing. This HCX option covers appliance failure only; for uplink resilience, use Application Path Resiliency or several uplinks.
- Service mesh
In HCX, the object that links a source compute profile to a destination one (together with their network profiles) and deploys paired service appliances, such as Interconnect and Network Extension, at both sites. Moving where appliances sit requires a resync, and adding further meshes scales out migration capacity.
- Source site
HCX term for the end of a site pair holding, in its vCenter, the VMs to be moved. Migrations (reverse ones too, in a unidirectional pair), service mesh and network extension are all initiated from there; its counterpart is the destination site.
- Traffic Engineering
HCX feature set for improving how Network Extension and Interconnect traffic crosses the underlay. It includes encrypting tunnels, Generic Receive Offload, TCP MSS clamping, and Application Path Resiliency (several paths prepared, one used at a time).