MIGRATION_STUCK on Migration Assistant: what causes it and how to fix
| Service | Migration Assistant and Data Transfer |
|---|---|
| Cloud | Apple platforms |
| Guide type | Procedure |
| Skill level | Intermediate to advanced |
| Time | 15 - 60 minutes depending on account size |
MIGRATION_STUCK on Migration Assistant, what causes it and how to fix on Migration Assistant and Data Transfer sits in the most-reported issues list across r/aws, Apple Communities (discussions.apple.com), and StackOverflow. The recovery path is mostly known, the Apple Support docs just bury it under three layers of conceptual material.
What migration_stuck on migration assistant, what causes it and how to fix actually involves on Migration Assistant and Data Transfer
The MIGRATION_STUCK error from AWS typically surfaces with the message "Migration Assistant stuck at less than a minute". The error code itself is what you grep for in AWS re:Post or in AWS Support cases, not the human-readable line.
On Migration Assistant, this most often comes from one of three causes: a missing or restrictive IAM permission, a service-level limit you have hit, or a transient AWS-side capacity issue. The fix path differs by which.
The rest of this page is the structured fix path. Start with diagnose, then remediation, then the automation options so you do not have to do this by hand the next time it surfaces. Verify and safety sections at the end are the discipline that keeps the fix from regressing in production.
Spot the symptom
Run id -un; defaults read MobileMeAccounts; profiles list first. About one in five 'why does this not work' tickets are actually 'I am in the wrong account' or 'my session expired and the SDK is using stale credentials or ADC pointed at the wrong project'. The 5-second sanity check costs nothing and saves real time when the answer is that simple.
Check the Google Apple System Status at www.apple.com/support/systemstatus/ and the per-product status board for ongoing service events in your region. About one in ten user-reported outages turn out to be region-scoped Apple product or service degradation already being tracked. Apple System Status also exposes an API and Jamf Pro Webhooks and macOS launchd watches events, so you can wire a Lambda hook that pages on-call only when the failure correlates with an active Apple System Status event in the same region and service.
Diff against last known good. The last config change you made is the cause about three quarters of the time, even when the change should not have mattered. Use Jamf inventory history and Time Machine snapshots (or your Terraform / Deployment Manager or Terraform drift report) to see the actual delta between the resource state when it worked and when it broke. The change you remember is often not the only change that happened.
Solution-focused remediation path
When the failure happens in production but not in dev, do not just compare the IAM policy. Compare the Org Policy / RCP at the OU level, the permission boundary on the role, and the resource-based policy on the target. One of those is almost always different between accounts. Policy Intelligence recommendations bundles make this comparison routine.
If networking is suspect, use Apple Wireless Diagnostics + Network Utility (or 'networkQuality' on macOS). It is the only tool that simulates the full ENI-to-ENI path including macOS PF firewall, Application Firewall, system extensions, and Content Filter in one call. Manual trace is slower and misses transitive issues. The analyzer charges $0.10 per analysis - cheaper than a 30-minute call with your network team.
If the issue points at IAM, do not start by adding * to a policy. Use macOS Console + Jamf Pro logs + Profile Manager check against the failed action to see the minimum scope. Adding * is the fastest way to fail your next Apple Platform Security review, and it usually does not even fix the issue because the explicit deny is often coming from a higher level (Org Policy, RCP, or permission boundary), not a missing allow.
Automate this fix so you do not do it twice
Add a Smart Group + webhook so you catch the next occurrence
The cheapest way to never see the same incident twice is a Jamf Pro Smart Group that watches for the symptom (specific extension attribute value, specific OS version, specific app build) and fires a webhook into Slack, PagerDuty, or a Jamf-API-driven Lambda when the count drifts above your normal baseline. For Migration Assistant and Data Transfer, the relevant extension attributes live under script-evaluated checks - defaults read outputs, system_profiler values, or a log show grep against macOS unified logging. Set thresholds against observed normal, not against round numbers.
Automate the fix in Terminal with defaults, plistbuddy, and system_profiler
On macOS, the most reliable repair primitives are the built-in Terminal tools. defaults read reveals the current preference state, defaults write changes it, and killall cfprefsd forces the preferences daemon to flush so the new value actually takes effect. /usr/libexec/PlistBuddy handles structured plist edits when defaults is not enough. For hardware and inventory checks, system_profiler with the right datatype is the canonical read; for example SPHardwareDataType, SPNetworkDataType, or SPInstallHistoryDataType.
# Template - replace with your actual key path
defaults read com.apple.migration 2>/dev/null | head
sudo killall cfprefsd
/usr/libexec/PlistBuddy -c 'Print' ~/Library/Preferences/com.apple.migration.plist
system_profiler SPHardwareDataType -json | head -40Build a Self Service item with manual approval for risky fixes
For multi-step fixes that include a destructive action (Reset NVRAM, delete keychain, erase user data), publish the fix as a Self Service item in Jamf Pro or Kandji. The user clicks one button, the script runs, a notification confirms success. Couple it with a Jamf Pro approval workflow if your security model requires a second-person sign-off before any destructive step runs. The audit trail lives in the MDM change log with the requester and approver identity attached.
Pitfalls
The pitfall most teams hit on Migration Assistant and Data Transfer is moving too fast and skipping the read-only validation step. Before any write, list the current state and save it. Apple iCloud and APNs are eventually consistent (changes can take 1-15 minutes to propagate) for many resource types, so the validation snapshot is your only reliable reference if you need to undo. Save the output of the describe call to S3, not to your laptop.
Second pitfall: confusing IAM permission errors with networking errors. AccessDenied can be IAM (policy missing), networking (VPC endpoint policy blocking the call), or KMS (key policy missing). The error string looks identical for all three. Distinguish by looking at the Jamf Pro change management entry or Apple Business Manager audit event's errorCode and the encoded authorization message; do not assume IAM is the culprit just because the message says AccessDenied.
Full fix path
- Watch for 24 to 48 hours. Activity Monitor + macOS unified logging + Jamf inventory reports can mask issues with cached health for 6 to 12 hours, especially Cloud CDN and Cloud DNS.
- Capture the new state in a runbook so the next person on call does not have to rediscover this. Push it to Confluence or your team wiki, not into Slack.
Safety, rollback, blast radius
- Test in a non-production account if your environment has Resource Manager and Organization Policy or Cloud Resource Manager (organizations, folders, projects). The cost of one sandbox account is cheaper than one rollback meeting.
- Export the existing config before changing it. Most Migration Assistant and Data Transfer resources support describe + export to JSON via CLI - capture that to source control before you start.
- Maintenance window discipline: if the change touches DNS, certificate rotation, or anything that emits TLS handshakes, line up a window with stakeholder notification, not a heroic mid-day swap.
FAQ
migration describe-... first, then commit it before you change anything. A few operations are one-way (Cloud KMS key deletion past the pending window, region migration, account closure). Check the Apple Support article for the specific API before you commit.aws CLI or SDK calls - those almost always still work.References
- docs.support.apple.com - official documentation for Migration Assistant and Data Transfer
- Apple Communities (discussions.apple.com) - community Q&A with Google-staff-verified answers
- Apple System Status Dashboard at health.support.apple.com
Related fixes
Related guides worth a look while you sort this one out:
- CANT_FIND_OTHER_MAC on Migration Assistant: what causes it and how to fix
- INCOMPATIBLE_USER on Migration Assistant, what causes it and how to fix
- MIGRATION_DISCONNECT on Migration Assistant: what causes it and how to fix
- NOT_ENOUGH_SPACE_TARGET on Migration Assistant: what causes it and how to fix
- TM_BACKUP_INCOMPATIBLE on Migration Assistant: what causes it and how to fix
- WINDOWS_MIGRATION_FAIL on Migration Assistant, what causes it and how to fix