Features/PostcopyRecovery

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Revision as of 10:42, 5 June 2019 by Peterx (talk | contribs) (Postcopy Recovery Procedures)

QMP handshake

{"execute": "qmp_capabilities"}
{"return": {}}

Enable postcopy

{"execute": "migrate-set-capabilities", "arguments": {"capabilities": [{"state": true, "capability": "postcopy-ram"}]}}
{"return": {}}

Start precopy migration

{"execute": "migrate", "arguments": {"uri": "unix:/tmp/migration-test-12K6jV/migsocket"}}
{"return": {}}

Start postcopy migration

{"execute": "migrate-start-postcopy"}
{"return": {}}
{"timestamp": {"seconds": 1559730429, "microseconds": 585575}, "event": "STOP"}
{"timestamp": {"seconds": 1559730429, "microseconds": 613592}, "event": "RESUME"}

Manually pause the postcopy migration before it completes. This emulates a network failure.

{"execute": "migrate-pause"}
{"return": {}}

Check the status of migration, should be "postcopy-paused"

{"execute": "query-migrate"}
{"return": {"status": "postcopy-paused", "socket-address": [{"path": "/tmp/migration-test-12K6jV/migsocket", "type": "unix"}]}}

Try to continue the previous postcopy migration, until it finishes

{"execute": "migrate-recover", "arguments": {"uri": "unix:/tmp/migration-test-12K6jV/migsocket-recover"}, "id": "recover-cmd"}
{"timestamp": {"seconds": 1559730429, "microseconds": 620072}, "event": "MIGRATION", "data": {"status": "setup"}}
{"return": {}, "id": "recover-cmd"}

Wait until migration completes (status becomes "completed")

{"execute": "query-migrate"}
{"return": {"postcopy-blocktime": 89, "status": "completed", "postcopy-vcpu-blocktime": [90]}}