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microvm exec

Run one command in a MicroVM that is already running

Terminal window
microvm exec [command] [options]
Parameter Kind Type Required Default Choices Help
command positional string no none any A shell command to run in the VM. Omitted only with --poll
--timeout flag string no 300 any How long to wait for the command, in seconds
--cwd flag string no none any Working directory
--env flag string no none any Set one environment variable for the command, as KEY=VALUE. Repeatable
--user flag string no none any Numeric uid to run the command as. Omitted runs as the daemon’s own user
--group flag string no none any Numeric gid to run the command as. Omitted keeps the daemon’s own group
--exec-id flag string no none any Use this exec id instead of a fresh one, making a retry idempotent
--poll flag string no none any Read an existing exec’s status and output instead of starting anything
--detach flag boolean no none any Start the command and return immediately, without waiting and without acking
--stream flag boolean no none any Stream output as it arrives rather than waiting for the whole thing
--from-offset flag string no none any Resume a stream at this byte offset. Only with --stream
--stdin flag boolean no none any Give the command a stdin pipe and feed it this process’s stdin, then close it
--reap flag boolean no none any Signal the command’s whole process group once its own child exits
--kill-on-timeout flag boolean no none any On ERR_TIMEOUT, stop the exec rather than leaving it running
--endpoint flag string no none any The VM’s endpoint, as reported by run
--agent-token flag string no none any The agent token delivered to the VM at launch
--microvm-id flag string no none any The MicroVM id, needed to mint the endpoint proxy token
--name flag string no none any The name run --keep --vm-name registered, standing in for the whole triple
--port flag string no none any The daemon’s port inside the guest
--state-dir flag path no none any Where the local state lives — the name registry, and exec’s per-VM history. Defaults to $MICROVM_STATE_DIR or ~/.microvm/runs
--region flag enum no none us-east-1, us-east-2, us-west-2, eu-west-1, ap-northeast-1 AWS region. Defaults to $AWS_REGION, then $AWS_DEFAULT_REGION, then us-east-1
--unlisted-region flag string no none any Use a region this client has not seen carry MicroVMs. Costs you the diagnostic

The 3 global flags (--json, --dense, --quiet) are accepted here as on every command, and are left out of the table above for that reason; see Global flags.

On success stdout carries one envelope whose type is microvm.exec. Its data object carries these keys: execId, exitCode, stdout, stderr, truncated, phase.

The envelope describes the fields around data. Response types lists every type the CLI emits and which commands share each one.

--stream changes what stdout carries: ndjson — one event object per line, then this envelope as the final line. The documented exception to the one-envelope rule: stream chunks are the command’s output, not progress, so they cannot go on stderr.

The final line is an envelope whose type is microvm.exec.stream, with these keys in data: execId, events, bytes, nextOffset, exitCode, truncated, gaps.

A failure exits with one of the statuses on Exit codes and writes the error shape on The envelope: a stable code to branch on, an exitCode that matches the process status, a human-readable error, and suggestions.

Where a failure is one this project has measured on the platform, the envelope’s finding names the section of the platform notes that documents it. The exit-code table links each one.

This page is generated from docs/manifest.json, the output of microvm manifest, which the CLI derives from its own argument tree. This page reads the exec entry of data.commands. site/scripts/gen-reference.mjs writes it into the site’s content directory on every pnpm run sync, so an edit made here is overwritten by the next run.

To change the page, change the source. Regenerate the source with mise run manifest from the repository root; mise run manifest:check fails when the committed file no longer matches what the binary emits.