Antivirus increases the published memory floor; attachment indexing can add further RAM demand.
Full-feature mail servers.Requisitos de hardware de Mailu: RAM, memoria de intercambio, almacenamiento de correo y puertos
Planifica el hardware de Mailu con sus requisitos oficiales mínimos de 1-3 GB de RAM más 1 GB de swap, almacenamiento de correo, DNS y puertos necesarios, con orientación práctica para ZimaOS.
Mailu requirements at a glance
Mailu is a multi-container mail server. Its official stable Docker documentation gives explicit RAM/swap minimums and requires careful DNS, ports and public-IP planning.
- RAM without ClamAV
- Official minimum: 1 GB RAM plus 1 GB swap.
- RAM with ClamAV
- Official minimum: 3 GB RAM plus 1 GB swap.
- CPU
- No numerical core/frequency minimum in the stable Compose requirements. Current master warns x86_64 deployments should support SSE4.2 for Rspamd/vectorscan.
- Storage
- No universal official disk minimum. Mailboxes, indexes, attachments, logs and backups determine capacity.
- Networking
- Mailu needs a public/reachable mail host, correct DNS, and multiple mail/web ports free on the host.
- Best Zima starting point
- ZimaBoard 2 832 has ample RAM for Mailu's published minimums; real suitability depends more on public IP, DNS, port ownership and mail deliverability.
From official requirements to the right setup
For Mailu, mail-server networking and DNS are as important as hardware.
-
Official requirements
Choose whether ClamAV is enabled. Budget 1 GB RAM + 1 GB swap without antivirus or 3 GB RAM + 1 GB swap with antivirus.
-
Confirm your needs
Verify the host CPU and Linux/Docker environment. Current Mailu master documentation warns that x86_64 Rspamd/vectorscan requires SSE4.2.
-
Leave room to grow
Plan a dedicated hostname, forward/reverse DNS, public IP or correct port forwarding, and free ports for SMTP/IMAP/HTTPS/ManageSieve services.
-
Run it on ZimaOS
On ZimaOS, use Install Custom App with Mailu's generated Compose files only after resolving port/firewall/DNS conflicts; persist /mailu data and maintain tested backups.
Check every playback client
- ClamAV enabled
- 1 GB swap
- Public IP
- Forward/reverse DNS
- Mail ports free
- Mailbox capacity
- Backup retention
- SSE4.2 on x86_64
Official minimum requirements
Mailu 2024.06 publishes explicit Compose memory/swap minimums while leaving CPU and disk capacity workload-dependent.
Use 1 GB RAM + 1 GB swap without antivirus or 3 GB RAM + 1 GB swap with ClamAV as the official stable baseline. Mail data and networking requirements must be planned separately.
| Requirement | Official minimum | What this supports |
|---|---|---|
| RAM without ClamAV | 1 GB | Current stable 2024.06 minimum. |
| RAM with ClamAV | 3 GB | Current stable 2024.06 minimum. |
| Swap | 1 GB | Required in both stable configurations. |
| CPU minimum | No numerical minimum published | Current master adds SSE4.2 guidance for x86_64 Rspamd. |
| Storage minimum | No numerical minimum published | Mailboxes, indexes and backups determine capacity. |
| Compose runtime | Docker Compose v2 | Current setup guidance. |
When to upgrade your hardware
Mailu should scale when mailboxes, antivirus/search features or concurrent users create sustained memory and I/O pressure.
ClamAV or attachment indexing is enabled
Mailbox/index storage grows
Concurrent IMAP/webmail users increase
Mail data, spam-filtering indexes and backups become the long-term disk driver.
Long-running domains with many users.More active mail sessions increase the multi-container stack's memory and I/O demand.
Team mail servers.Plan hardware growth with confidence
Scale Mailu around mail storage and service concurrency while preserving correct mail-server networking.
Use SSD-backed mail/index storage
Mail indexes and database operations benefit from reliable low-latency storage.
Use SATA/NVMe with ZimaBoard 2 or SSD tiers on ZimaCube 2.Use 8 GB for comfortable small deployments
Provides substantial margin over the 3 GB antivirus-enabled baseline plus Docker overhead.
ZimaBoard 2 832.Move to 16 GB for more users/features
Extra RAM helps antivirus, webmail, indexes and other services coexist.
ZimaBoard 2 1664.Use multi-drive storage for larger mailbox retention
Mailbox data and backups can justify a broader storage platform.
ZimaCube 2 Standard or Pro.Can it run on ZimaOS?
Mailu is not currently confirmed as a public official one-click ZimaOS App Store page in the sources checked for this guide. It can be deployed through Install Custom App, but mail-server DNS, ports and firewall requirements require careful host-level planning.
Custom install Mailu in ZimaOS
Use Install Custom App with Mailu's generated Compose configuration only after confirming all required host ports are free and DNS/public-IP requirements are satisfied.
Custom install Mailu in the ZimaOS app ↗Follow Mailu's stable Compose requirements
Mailu 2024.06 documents 1 GB RAM + 1 GB swap without ClamAV and 3 GB + 1 GB swap with ClamAV.
Review Mailu requirements ↗Generate the Mailu configuration carefully
The official setup utility creates docker-compose.yml and mailu.env and requires correct TLS/DNS/network settings.
Review Mailu setup ↗Choose Zima hardware for Mailu
Mailu's published RAM minimums fit even ZimaBoard 2 832; the harder constraints are ports, public IP/DNS and durable mailbox storage.
Is this a small private Mailu server or a larger multi-user mailbox platform?
Small private mail server
Use ZimaBoard 2 832 with SSD-backed mail storage and correct public networking.
- Best starting pointZimaBoard 2 832
More users, antivirus/search and mailbox retention
Use more RAM and expandable storage.
- More memory headroomZimaBoard 2 1664
- Storage-first platformZimaCube 2 Standard
These are practical hardware recommendations, not mail-deliverability guarantees. DNS reputation, reverse DNS and ISP/cloud SMTP policies can dominate real-world success.
| Zima hardware | Best for | Example workload | Core configuration | Recommended boundary | Next step |
|---|---|---|---|---|---|
| ZimaBoard 2 832 | Small Mailu deployments. | Mailu with antivirus enabled and modest mailbox volume. |
|
8 GB is well above Mailu's 3 GB antivirus baseline; public IP/DNS/ports remain essential. | Get Now |
| ZimaBoard 2 1664 | More users and mail services. | Larger mailbox/search/antivirus memory budget and co-hosted services. |
|
16 GB is headroom beyond the official minimum. | Get Now |
| ZimaCube 2 Standard | Mailbox-heavy deployments and broader backup needs. | Mailu plus multi-drive mail retention and backups. |
|
Choose it primarily for storage capacity. | Get Now |
What the Press Says
Highlights from trusted reviewers worldwide.
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Construí um servidor de uso pessoal. O desempenho está muito bom e funciona perfeitamente onde quer que eu esteja. A surpresa é não dependermos de grandes estruturas para termos nosso próprio servidor de dados. Como iniciante, estou gostando bastante do ZimaOS, pois ele é simples e eficiente.
Frequently asked questions
These answers cover Mailu RAM, swap, ClamAV, DNS, ports and ZimaOS deployment.
How much RAM does Mailu need without antivirus?
Mailu 2024.06 requires at least 1 GB RAM plus 1 GB swap without ClamAV.
How much RAM does Mailu need with ClamAV?
The stable requirement is 3 GB RAM plus 1 GB swap.
Does Mailu publish a CPU minimum?
The stable Compose requirements do not publish a numerical CPU minimum; current master warns x86_64 Rspamd needs SSE4.2.
How much storage does Mailu need?
No universal minimum is published; mailbox data, indexes, attachments and backups determine capacity.
Does Mailu need a GPU?
No dedicated GPU is required.
Can ZimaBoard 2 run Mailu?
Yes from a resource perspective; even the 8 GB model exceeds the published antivirus-enabled RAM minimum.
Why are DNS and ports critical for Mailu?
A mail server needs correct forward/reverse DNS, reachable SMTP/IMAP services and ports not already occupied by other host applications.
Which Mailu version is stable?
The current documentation identifies 2024.06 as the stable release branch.
What sources informed this Mailu hardware guide?
The guide uses Mailu's stable Compose requirements, setup guidance and current CPU compatibility notes plus current Zima product pages.
