---
title: "VAST SyncEngine 3.4.1 Release Notes"
slug: "vast-syncengine-3-4-1-release-notes-3-4"
updated: 2026-11-04T11:57:42Z
published: 2026-11-04T11:57:42Z
canonical: "docs.vastdata.com/vast-syncengine-3-4-1-release-notes-3-4"
---

> ## Documentation Index
> Fetch the complete documentation index at: https://docs.vastdata.com/llms.txt
> Use this file to discover all available pages before exploring further.

# VAST SyncEngine 3.4.1 Release Notes

VAST SyncEngine 3.4.1 has been released in November, 2026. The release includes: ​

## New Features

​​

### Sync Catalog for NFS Migrations

SyncEngine 3.4.1 lets you use a dedicated Postgres database to keep track of items being migrated from an NFS export to VAST NFS. The sync catalog is optional; it is created in addition to the migration scan index. To create a sync catalog:

1. Create an index connector (use **Postgres** connector type).
2. Attach the connector to the NFS migration.

## Enhancements

### NFS

You can set NFS RPC rate limits for the NFS connector. To do so: - In SyncEngine UI, use the **API calls per second** and/or **Bytes per second** fields in the **Rate limits** step of the connector creation wizard. - In SyncEngine CLI, include the `--api-calls-per-second` and/or `--bytes-per-second` options on the `connector create` command.

### NFS and POSIX

​Exclude lists used in NFS and POSIX migrations no longer accept patterns with relative paths. All paths specified for the exclude list must be absolute.

### VAST S3 Rate Limits

This release supports VAST S3 connector rate limits. To set the rate limits:

- In SyncEngine UI, use the **API calls per second** and **Bytes per second** fields in the VAST S3 connector settings.
- In SyncEngine CLI, include the `--api-calls-per-second` and`--bytes-per-second` options on the `connector create` command.

### SyncEngline CLI for Rate Limits

Rate limits can now be configured via SyncEngine CLI. To do so, include the `--api-calls-per-second` and `--bytes-per-second` options on the `connector create` command.

> **Note:** The `--bytes-per-second` option is not available for the index connector.

### Aborting Migration Jobs

You can abort a running migration job as follows: - In SyncEngine UI, use the abort control in the **Migrations** page. - In SyncEngine CLI, run the `migration abort --migration-id <migration ID>` command.

### Batch Sizing via CLI

The **Batch sizing** step has been removed from migration settings in the SyncEngine UI. To configure batch sizing, use the `--scan-batch-size-gb` and `--scan-batch-file-count` options on the `connector create` command in SyncEngine CLI.