What causes "cp: cannot flush the created file %s: %s" in ipfs/kubo?

Check disk space and datastore health (`ipfs repo stat`, daemon logs)

cp: cannot flush the created file %s: %s

Error message

cp: cannot flush the created file %s: %s

What it means

After successfully placing the node, `ipfs files cp --flush` (flush is enabled by default) flushes the created file via mfs.FlushPath; this error wraps a failure flushing dst itself. The node was placed but its data could not be committed from the in-memory MFS to the DAG service/datastore.

Source

Thrown at core/commands/files.go:601

		if force {
			if err = unlinkNodeIfExists(nd, dst); err != nil {
				return fmt.Errorf("cp: cannot unlink existing file: %s", err)
			}
		}

		flush, _ := req.Options[filesFlushOptionName].(bool)

		if err := updateNoFlushCounter(nd, flush); err != nil {
			return err
		}

		err = mfs.PutNode(nd.FilesRoot, dst, node)
		if err != nil {
			return fmt.Errorf("cp: cannot put node in path %s: %s", dst, err)
		}
		if flush {
			if _, err := mfs.FlushPath(req.Context, nd.FilesRoot, dst); err != nil {
				return fmt.Errorf("cp: cannot flush the created file %s: %s", dst, err)
			}
			// Flush parent to clear directory cache and free memory.
			parent := gopath.Dir(dst)
			if _, err = mfs.FlushPath(req.Context, nd.FilesRoot, parent); err != nil {
				return fmt.Errorf("cp: cannot flush the created file's parent folder %s: %s", dst, err)
			}
		}

		return nil
	},
}

func getNodeFromPath(ctx context.Context, node *core.IpfsNode, api iface.CoreAPI, p string) (ipld.Node, error) {
	// A content path or native IPFS URI (/ipfs/cid, ipfs://cid, /ipns/name, ...)
	// is resolved through the DAG. Anything else is treated as an MFS path.
	if pth, err := path.NewPathFromURI(p); err == nil {
		return api.ResolveNode(ctx, pth)
	}

View on GitHub (pinned to 329838acdf)

Solutions

Check disk space and datastore health (`ipfs repo stat`, daemon logs)
Re-run the copy; if dst was concurrently removed, serialize concurrent MFS writers
Run `ipfs files flush /` to reconcile MFS state, then retry
Investigate datastore errors in daemon logs (`GOLOG_LOG_LEVEL=debug ipfs daemon`)

Example fix

null

Defensive patterns

Strategy: retry

Validate before calling

// check repo headroom before large copies
run("ipfs", "repo", "stat") // verify free space / quota

Try / catch

err := ipfsFilesCp(src, dst)
if err != nil && strings.Contains(err.Error(), "cannot flush the created file") {
    time.Sleep(backoff)
    run("ipfs", "files", "flush", "/")
    err = ipfsFilesCp(src, dst)
}

Prevention

Monitor disk space for the repo datastore
Serialize MFS writes; avoid concurrent writers to the same path
Run `ipfs files flush /` after bulk operations and check daemon logs

When it happens

Trigger: Running `ipfs files cp` with flush enabled where mfs.FlushPath on dst fails — e.g. underlying blockservice/datastore write errors, disk full, or the just-placed path was concurrently removed by another operation.

Common situations: Full disk or datastore quota during a large copy; concurrent MFS operations from another CLI/API client removing dst between put and flush; datastore (e.g. badger) corruption.

Related errors

AI-assisted analysis of ipfs/kubo@329838acdf (2026-09-03). Data as JSON: /api/errors/e05981d0f69e368c. Report an issue: GitHub.