SynologyとVirtual Machine Manager vs VMM Pro：無料版で既にできること

Virtual Machine Manager is the free hypervisor Synology ships for its NAS, and it does far more than most buyers expect before they spend anything on VMM Pro. It runs Windows, Linux and Virtual DSM guests, takes snapshots, and can even join up to seven NAS units into one cluster. VMM Pro is the paid license that turns that cluster into something that protects itself: live migration, high availability, scheduled replication to another host and a much higher snapshot ceiling. This guide compares the two editions of Virtual Machine Manager using Synology’s own specification sheet, explains how VMM Pro is licensed, and shows how to test it for 30 days before you decide.

SynoPower Clubポイント： When I worked on the support side of Synology, the most common VMM Pro question was not what it does, it was whether someone needed it at all. Half the people asking owned one NAS and would never use a single Pro feature. The other half had already lost a weekend restoring a guest by hand and were ready to pay anything. Virtual Machine Manager on its own is a genuinely capable hypervisor. The moment you own a second NAS and want your guests to outlive the first one, that is when the Pro license starts paying for itself.

What Synology Virtual Machine Manager Does for Free #

Virtual Machine Manager installs from Package Center on any compatible NAS with a Btrfs volume, and the free edition is not a trial or a demo. It runs production workloads with no time limit.

• Runs Windows, Linux and Virtual DSM guests side by side on one NAS.
• Takes up to 32 snapshots per virtual machine for quick rollback.
• Includes one Virtual DSM license per host, free for as long as you use it.
• Allows up to 4 virtual switches, and 2 share links per host.
• Joins up to 7 Synology NAS hosts into a single cluster you manage from one console.

That last point surprises many people. Clustering itself is not a Pro feature. What the free edition cannot do is move or protect guests across the hosts in that cluster, and that is exactly the gap VMM Pro fills.

Virtual Machine Manager vs VMM Pro: The Specification Sheet #

Synology publishes the split between the two editions in the Virtual Machine Manager technical specifications. This table summarises it; check the official page before buying, because Synology does revise it between DSM releases.

能力	Free edition	VMM Pro
Hosts in one cluster	Up to 7	Up to 7
Snapshots per virtual machine	32	255
Virtual switches	4	4,096
Share links per host	2	16
Live migration between hosts	いいえ	はい
High availability	いいえ	はい
Protection plans with scheduled replication	いいえ	はい
Run a guest or migrate storage to a remote host	いいえ	はい
Free Virtual DSM licenses	1 per host	1 per host

Read the table from the bottom up and a pattern appears. Everything that happens inside one NAS is available in both editions. Everything that happens between two NAS units, moving a running guest, restarting it elsewhere after a failure, or copying its snapshots to another box on a schedule, needs VMM Pro.

Three Myths About VMM Pro Worth Clearing Up #

A lot of what circulates about the Pro edition is out of date or simply wrong. These three come up most often in questions we receive.

It is not a perpetual license. VMM Pro is sold as a 3-node or 7-node pack with a fixed term of one, three or five years, and Synology states that licenses cannot be refunded once activated.

It does not unlock more Virtual DSM instances. Each host runs one Virtual DSM free in either edition. Additional Virtual DSM guests need Virtual DSMライセンス, which are a separate product. Our guide on adding and mapping Virtual DSM licenses covers how those work.

It is not required to build a cluster. The free edition already manages up to seven hosts. Pro adds the cross-host features on top of a cluster you may already have.

Try VMM Pro in Virtual Machine Manager in 4 Steps #

Every compatible Synology NAS is eligible for a one-time 30-day VMM Pro trial, started from inside Virtual Machine Manager. Use it on the hardware you actually own, with the guests you actually run.

Which Pro Features Matter Most in Practice #

Not every Pro feature carries equal weight. In the environments we see, the value lands in this order.

Protection plans with remote replication come first. They copy each guest’s snapshots to another host on a schedule, so a failed NAS costs you minutes of recovery instead of a restore from backup. Remote replication needs at least two hosts, both with Btrfs volumes.

Live migration is second. It moves a running guest to another host with no interruption, which turns firmware updates and disk replacements into daytime jobs instead of midnight maintenance windows.

High availability is the most powerful and the most demanding. Synology requires at least three hosts in the cluster, and the hosts must stay online to agree on cluster health. When a host fails, protected guests restart on another host automatically.

Who Needs Virtual Machine Manager Pro and Who Does Not #

The decision is less about company size than about how many NAS units you own and how you want to recover from failure.

• One NAS, happy to restore by hand: stay on the free Virtual Machine Manager. None of the Pro features apply to a single host.
• Two NAS units: VMM Pro gives you replication and live migration between them. High availability still needs a third host.
• Three or more NAS units: all Pro features are available, including automatic failover with high availability.
• Hundreds of snapshots or many virtual networks: the 255 snapshot and 4,096 switch limits alone can justify Pro on a busy host.

If you fall into the second or third group, our write-up of the three-node Synology virtual machine cluster that runs this store shows what a production setup looks like.

How VMM Pro Licensing Works #

A VMM Pro license covers a number of nodes in one cluster rather than a single NAS. Synology sells 3-node and 7-node packs, matching the seven-host cluster maximum, with terms of one, three or five years. At SynoPower Club we stock the 3-node and 7-node packs in one-year and three-year terms, delivered by email as soon as payment clears.

Two practical notes. First, count every host you want the Pro features to apply to, including a standby node that is usually powered off. Second, plan activation around the trial: licenses cannot be refunded once activated, so use the 30 days to confirm the features work on your hardware first.

Hardware Planning Before You Upgrade #

VMM Pro does not make a weak host stronger, so check capacity before paying for cross-host features. Synology’s white paper recommends an uneven number of cluster nodes so the hosts can decide cluster health by majority, a static IP on every host, and ideally a separate network or VLAN for cluster traffic.

Memory is usually the limit. A running guest’s memory is reserved on its host, so every host that might receive a failed-over guest needs enough free memory to take it. Our right-sizing walkthrough shows how we cut a production guest in half to create that headroom.

Virtual Machine Manager Limits and Caveats #

Both editions share the same hardware requirement: VMM only runs on compatible models with a Btrfs volume, and Synology’s compatibility list is the final word on which NAS units qualify.

The free edition’s 32-snapshot ceiling is easy to hit with an automatic schedule. A plan that snapshots every twelve hours reaches it in sixteen days, after which the oldest snapshots rotate out. Lock the snapshots you need to keep.

High availability is not the same as backup. It restarts a guest after hardware fails, but it will happily restart a guest whose data was damaged by mistake or malware. Keep snapshots and an off-host copy regardless of edition.

Finally, treat any feature table, including ours, as a snapshot in time. Synology has changed the edition split before, so confirm against the official specification page on the day you buy.

Where to Learn More From Synology #

Synology’s white paper on virtualization is the most complete official source on cluster design, and the knowledge center covers each Pro feature step by step. The references below link to both, and the videos show Virtual Machine Manager in use.

よくある質問 #

参考資料とビデオチュートリアル #

• Virtual Machine Manager technical specifications, the official split between the free edition and VMM Pro.
• VMM Pro License Pack, covering 3-node and 7-node packs, terms and the 30-day trial.
• Synology VMM white paper, with cluster design, quorum and network recommendations.
• High Availability in Virtual Machine Manager, the knowledge center article on automatic failover.
• Virtual Machine Manager requirements and limitations, including supported models and file systems.

An official Synology webinar on Virtual Machine Manager, followed by two independent walkthroughs of building guests on a Synology NAS.

Ready to add cross-host protection? Get a VMM Proライセンス, or browse every Synology license on SynoPower Club.