Webmail search, caching and large message lists can raise request time and memory use.
Power users with large mailboxes.متطلبات أجهزة Roundcube: ذاكرة الوصول العشوائي، وحدة المعالجة المركزية، PHP وقاعدة البيانات
خطط لمواصفات أجهزة Roundcube لتشغيل PHP وقاعدة البيانات وIMAP وSMTP والمرفقات وDocker، مع توصيات عملية للتثبيت المخصّص على ZimaOS.
Roundcube requirements at a glance
Roundcube is a webmail client, not a mail server. The IMAP/SMTP server handles the actual mailbox workload.
- RAM
- No numerical whole-host RAM minimum published. The installation guide suggests PHP memory_limit=64M, but that is a PHP process setting, not server RAM.
- CPU
- No numerical official core minimum. Normal webmail use is lightweight; plugins, search and large attachments add load.
- PHP
- Roundcube 1.7 requires PHP 8.1 or newer and currently supports up to PHP 8.5.
- Database
- Roundcube 1.7 supports MySQL/MariaDB, PostgreSQL and SQLite through PDO; current Docker guidance commonly uses MySQL for production-style deployments.
- Mail backend
- An IMAP server and SMTP server are required; Roundcube does not replace them.
- Best Zima starting point
- ZimaBoard 2 832 is vastly more than enough for Roundcube itself; size the host primarily for the mail server if it is co-located.
From official requirements to the right setup
Size Roundcube as a lightweight PHP frontend and keep mail-server requirements separate.
-
Official requirements
Use Roundcube 1.7 with PHP 8.1–8.5 and point the web server document root at public_html as required by the 1.7 release.
-
Confirm your needs
Provide a supported database and external IMAP/SMTP services. Do not count the IMAP mailbox server's CPU/RAM/storage as Roundcube's own requirement.
-
Leave room to grow
Set PHP upload/memory limits according to attachment sizes and persist the Roundcube database/configuration when using Docker.
-
Run it on ZimaOS
On ZimaOS, use Install Custom App with the official Roundcube container, persist /var/roundcube/db or use an external MySQL/PostgreSQL database, and map the web port behind HTTPS.
Check every playback client
- PHP 8.1–8.5
- IMAP server
- SMTP server
- Database choice
- Attachment size
- Persistent database
- HTTPS/reverse proxy
- Plugins
Official minimum requirements
Roundcube publishes software requirements and PHP settings rather than numerical whole-host hardware minimums.
Do not convert PHP memory_limit values into server RAM requirements. Roundcube itself is light; IMAP/SMTP services and mailbox storage are separate workloads.
| Requirement | Official minimum | What this supports |
|---|---|---|
| Whole-host RAM minimum | No numerical official minimum published | PHP memory_limit is not equivalent to host RAM. |
| CPU minimum | No numerical official minimum published | Normal webmail frontend load is light. |
| PHP | 8.1–8.5 | Current Roundcube 1.7 support range. |
| Database | MySQL/MariaDB, PostgreSQL or SQLite | Supported through PDO in current 1.7 code. |
| PHP memory_limit example | 64M | Installation guide suggestion, not a host RAM minimum. |
| Mail backend | IMAP + SMTP required | Roundcube is a client frontend, not the mail server. |
When to upgrade your hardware
Roundcube itself rarely justifies larger hardware; scale when the database, plugins or co-located mail server become heavier.
Large mailboxes and search increase PHP/IMAP work
Plugins and attachment handling grow
The mail backend shares the same host
Image processing, LDAP, Sieve and larger uploads add PHP and network work.
Feature-rich webmail deployments.IMAP storage, spam filtering and SMTP can dwarf Roundcube's own footprint.
All-in-one mail servers.Plan hardware growth with confidence
Scale Roundcube around the broader mail stack rather than the frontend alone.
Keep Roundcube on ZimaBoard 2 832
The webmail frontend is lightweight and does not need high-end compute.
ZimaBoard 2 832.Use a server database for larger shared use
MySQL/PostgreSQL provides a more robust shared-database path than container-local SQLite.
Any Zima host with SSD-backed database storage.Use 16 GB if the full mail server shares the host
Extra RAM is for IMAP, SMTP, spam filtering and database services, not Roundcube alone.
ZimaBoard 2 1664.Use ZimaCube when mailbox storage dominates
Large mail retention and backups may justify multi-drive capacity.
ZimaCube 2 Standard.Can it run on ZimaOS?
No public official ZimaOS one-click Roundcube App Store page was verified for this guide. Roundcube can be deployed through Install Custom App using the official Roundcube container.
Custom install Roundcube in ZimaOS
Use Install Custom App with roundcube/roundcubemail, persist the database/configuration, and point it to your existing IMAP and SMTP services.
Custom install Roundcube in the ZimaOS app ↗Use Roundcube's official Docker project
The official Docker repository defaults to SQLite for metadata and supports MySQL or PostgreSQL for more production-oriented deployments.
Review Roundcube Docker image ↗Follow Roundcube 1.7 requirements
Roundcube 1.7 requires PHP 8.1+ and a public_html document root in manual web-server deployments.
Review Roundcube installation ↗Choose Zima hardware for Roundcube
Roundcube is one of the lightest apps in this batch; hardware choice should follow the mail backend, not the frontend.
Is Roundcube just a frontend to an external mail server or part of an all-in-one mail host?
External IMAP/SMTP backend
Use the smallest current ZimaBoard 2; Roundcube needs very little compute.
- Best starting pointZimaBoard 2 832
Full mail stack on one host
Add RAM and storage for the actual mail server services.
- More RAM headroomZimaBoard 2 1664
- Mailbox-storage platformZimaCube 2 Standard
These recommendations apply to Roundcube itself; IMAP/SMTP server requirements can be much larger.
| Zima hardware | Best for | Example workload | Core configuration | Recommended boundary | Next step |
|---|---|---|---|---|---|
| ZimaBoard 2 832 | Roundcube with external IMAP/SMTP. | Roundcube PHP frontend, small database and plugins. |
|
The mail server is the real workload; Roundcube alone uses little of this hardware. | Get Now |
| ZimaBoard 2 1664 | Roundcube on a broader all-in-one mail host. | Roundcube plus IMAP/SMTP, database and filtering services. |
|
Extra RAM is for the mail stack, not Roundcube. | Get Now |
| ZimaCube 2 Standard | Mailbox-heavy self-hosted mail systems. | Roundcube plus large mail storage and backups. |
|
Choose it for mailbox capacity rather than the Roundcube frontend. | Get Now |
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Frequently asked questions
These answers cover Roundcube RAM, CPU, PHP, databases, IMAP/SMTP and ZimaOS deployment.
How much RAM does Roundcube need?
Roundcube does not publish a numerical whole-server RAM minimum.
Is Roundcube's PHP memory_limit the same as host RAM?
No. The installation guide's 64M suggestion is a PHP process setting, not a server hardware minimum.
Which PHP version does Roundcube 1.7 require?
Roundcube 1.7 supports PHP 8.1 through 8.5.
Which databases does Roundcube support?
Current 1.7 code supports MySQL/MariaDB, PostgreSQL and SQLite through PDO.
Does Roundcube include an IMAP or SMTP server?
No. It requires external IMAP and SMTP services.
Does Roundcube need a GPU?
No dedicated GPU is required.
Can ZimaBoard 2 run Roundcube?
Yes. The 8 GB model is far more than enough for the Roundcube frontend.
When should I choose larger Zima hardware?
When the co-located mail server, mailbox storage or other services—not Roundcube—need it.
What sources informed this Roundcube hardware guide?
Current Roundcube 1.7 release, installation and official Docker documentation plus current Zima product pages.
