KVM requirements
Overview
This topic outlines the requirements for deploying the DCT appliance on a KVM-based hypervisor, including recommended configuration parameters. Deploying DCT on KVM requires a qcow2 image. Download it from the Delphix download site under the DCT Appliance folder. See KVM deployment for step-by-step instructions.
Virtual CPUs
-
8 vCPUs minimum: CPU resource shortfalls can occur on an over-committed host. CPU reservations are strongly recommended so DCT is guaranteed its full vCPU allocation even when the host is under pressure.
-
Reserve host CPU capacity: Do not allocate all available physical CPUs to virtual machines. Reserve a minimum of 8-10% of host vCPUs for KVM hypervisor operations.
Memory
-
16 GB RAM minimum: Sufficient for most DCT deployments regardless of the number of registered engines.
-
32-64 GB RAM: Recommended when using Delphix AI Services features, which significantly increase memory pressure.
-
Memory reservation (recommended): Configure a memory reservation for the DCT VM so it is not forced to swap pages during host memory pressure. A swapped page takes orders of magnitude longer to return to physical memory from the KVM swap device than to stay resident.
Network
DCT communicates with registered Continuous Data and Continuous Compliance engines exclusively over HTTPS. It does not use NFS, iSCSI, or DSP, and does not move bulk data between the appliance and the engines. This means DCT has significantly lower network bandwidth requirements than a Continuous Data engine.
-
Standard virtual ethernet adapter: A standard virtio NIC is sufficient. HTTPS control-plane traffic does not require a high-throughput adapter.
-
Dedicated NIC (optional): If the KVM host carries high network load from other VMs, consider dedicating a physical NIC to the DCT VM for consistent API response latency.
Storage
DCT requires two virtual disks: a system disk and a metadata volume. Unlike Continuous Data, DCT does not require a DxFS storage pool or additional data disks.
|
Disk |
Size |
Format |
Notes |
|---|---|---|---|
|
System disk |
128 GB |
qcow2 |
Ships at 128 GB in the published image. |
|
Metadata volume |
50 GB minimum |
qcow2 |
Stores DCT application metadata. |
Provision the disks from KVM host storage backed by redundant storage (for example, RAID or equivalent). DCT does not protect against data loss originating at the hypervisor or storage layer.