Azure Virtual Machine Scale Set (VMSS)
Arpio replicates Azure Virtual Machine Scale Sets with their networking, scaling, and VM profile configurations, enabling auto-scaling workloads to be restored in recovery environments.
Virtual Machine Scale Set
Arpio replicates Virtual Machine Scale Sets by capturing their VM profile, network interface configurations, and scaling settings. At recovery time, the scale set is recreated in the recovery environment with references translated to recovery subnets, network security groups, load balancers, and application gateways. New VM instances are provisioned by Azure from the scale set's image reference rather than restored from snapshots, so per-instance data is not preserved across recovery.
Scale sets that use password-based authentication (Windows, or Linux without SSH key configuration) require the administrator password to be stored in a Key Vault secret and referenced via the arpio-config:admin-password-secret tag. Scale sets that use Linux SSH key authentication do not require this tag.
The following attributes are translated during replication:
| Attribute | Translation Method |
|---|---|
| Subnet References | Translated to recovery subnets |
| Network Security Group References | Translated to recovery network security groups |
| Load Balancer Backend Address Pools | Translated to recovery load balancer pools |
| Load Balancer Inbound NAT Pools | Translated to recovery load balancer NAT pools |
| Application Gateway Backend Address Pools | Translated to recovery application gateway pools |
| Health Probe | Translated to recovery load balancer probe |
| Image Reference | Translated to recovery virtual machine image when one exists |
| Encryption Identity | Translated to recovery user-assigned identity |
| User Data | Translated for environment-specific references |
| Boot Diagnostics Storage URI | Translated to recovery storage account |
| Administrator Password | Retrieved from the Key Vault URL specified in the arpio-config:admin-password-secret tag |
The following resources are automatically selected into recovery points when a Virtual Machine Scale Set is selected:
- Virtual network subnets referenced by the scale set's network interface configurations
- Network security groups referenced by the scale set's network interface configurations
- Load balancers referenced by backend pools or inbound NAT pools
- Application gateways referenced by backend pools
- Custom Virtual Machine Images referenced by the scale set
- Key Vault containing the administrator password secret (when the
arpio-config:admin-password-secrettag is set)
Limitations
- Marketplace and platform images — Arpio automatically backs up and restores custom images referenced by a scale set. If the scale set references a marketplace or platform image, the customer must ensure that image is available in the recovery subscription and region.
customDatais not recovered — Azure does not exposecustomDatathrough its API, so Arpio cannot replicate it. Recovered scale set instances will be provisioned without the originalcustomDatavalue.