Documentation Index
Fetch the complete documentation index at: https://docs.xloud.tech/llms.txt
Use this file to discover all available pages before exploring further.
Overview
Cutover is the final step of a warm migration. XMS takes a last incremental sync to bring the target volume fully up to date, powers off the source VM, runs guest conversion against the target volume, and launches the migrated instance on Xloud. When cutover completes, the source VM is left powered off and the target instance is the authoritative copy.Prerequisites
- A warm migration job in Ready state (full sync completed and at least one successful incremental sync)
- A maintenance window long enough for the final sync, guest conversion, and target boot — typically a few minutes for small workloads
- Agreement from the workload owner that the source VM can be powered off
Lifecycle
| Phase | What Happens |
|---|---|
| Final Delta | A last incremental sync transfers any blocks that changed since the previous sync. |
| Power Off Source | XMS issues a graceful shutdown to the source VM. If the guest does not respond in time, a hard power off is used. |
| Guest Fixes | VirtIO drivers are injected, the boot loader is repaired, and hypervisor-specific tooling is removed. |
| Finalize | The target volume is marked bootable and attached to the target instance record. |
| Boot Target | The target Xloud instance is launched from the migrated volume. |
| Completed | Cutover is complete — the target instance is running on Xloud. |
Trigger Cutover
- Dashboard
- CLI
Open the warm migration job
Navigate to Migration → Warm Migration and select the job you want
to cut over. The job must be in Ready state.
Confirm the lag is acceptable
Check the Lag column. A low lag means the final delta sync will be
quick. If the lag is high, trigger a Sync Now first and wait for
it to finish before starting cutover.
Click Cutover
Click Cutover. A confirmation dialog summarizes what happens next:
- Final incremental sync runs immediately
- Source VM is powered off
- Guest conversion runs against the target volume
- Target Xloud instance is launched
Watch live progress
The panel shows live progress for every phase. Events stream in real
time — final delta bytes, source power off state, guest conversion
steps, and target boot.
Job status reaches Completed and the target instance is visible in the Xloud Dashboard.
Validate the target
Click the link to the target instance, confirm it reaches an active
power state, and proceed to
post-migration validation.
What Happens to the Source VM
During Cutover
XMS issues a graceful shutdown to the source. If the guest does not
respond within the configured timeout, a hard power off is used to keep
the cutover window tight.
After Cutover
The source VM stays powered off in its source environment. XMS does not
delete the source — decommission it manually only after you have validated
the migrated workload on Xloud.
Cutover Window
The cutover window is the time between the start of the final delta sync and the target instance booting on Xloud. It determines how long the workload is unavailable. Typical contributions:| Phase | Typical Duration |
|---|---|
| Final delta sync | Seconds to a few minutes — depends on churn since the last incremental |
| Source power off | Seconds to a minute — graceful shutdown of the guest |
| Guest fixes | 30 seconds to a few minutes — VirtIO driver injection and boot loader repair |
| Finalize and boot | Under a minute — attach volume and launch target instance |
Rollback
If cutover fails at any phase before the target boots, XMS leaves the source VM powered off and the job in Failed state. You can:- Power the source VM back on manually — the source data is unchanged
- Inspect the failure in the event stream and in Troubleshooting
- Re-trigger cutover once the underlying issue is resolved
Next Steps
Post-Migration Validation
Verify the migrated instance boots, networks, and behaves correctly
Troubleshooting
Diagnose failed cutovers, stuck guest conversion, and boot errors
Warm Migration
Review the warm migration lifecycle and sync mechanics