Most failed OnlyOffice installs were lost before the first command was typed — the server was too small, or the address was an afterthought. Fifteen minutes of honest planning makes the actual install boring, which is exactly what you want.
The Document Server runs a full office suite rendering engine, a conversion service, a database and a cache — for every user, at the same time. It is honest to say it plainly: this is not a light service, and squeezing it onto an already busy tiny VPS is the most common cause of a slow, crashing editor. This page covers the planning decisions that matter — resources, address, and where it should live — so the install itself becomes a formality.
OnlyOffice's own documentation asks for a few gigabytes of RAM as a floor for the Document Server, and real-world use agrees: the more people edit at once, the more memory the document services consume. Plan for the server to have comfortable spare RAM after Nextcloud itself is counted. If the machine starts swapping, the editor does not get a little slower — it falls over for everyone at the same time.
Opening and converting documents is CPU work, so a multi-core processor matters more than a slightly higher clock speed. The Document Server also keeps a working cache of open documents, so give it a fast SSD and honest free space rather than the last corner of a nearly full disk. Old spinning disks make large spreadsheets feel broken even when everything is configured correctly.
Two honest options. Same machine as Nextcloud — simpler, cheaper, fine for a small team, and Docker keeps the services tidy. Its own VM or server — more moving parts, but the editor can grow without fighting Nextcloud for memory, and you can restart one without touching the other. For an office where documents are edited all day, the separate machine earns its keep. For a home lab or a handful of users, one good machine is perfectly respectable.
Decide the addresses now: Nextcloud keeps its name, and the Document Server gets its own subdomain such as office.example.com with a DNS record pointing at the right machine. The Document Server listens on port 80 by default, or 443 when HTTPS is configured — make sure those ports are free on the host and reachable through the firewall. Discovering at install time that another service already owns port 80 is a silly way to lose an evening.
One comforting fact for planning backups: your documents stay in Nextcloud. The Document Server holds settings, certificates, logs and a cache of documents currently being edited — important for the service to run, but it is not your file archive. Back up the volume folders so you can restore the service quickly, and keep your real backup effort on Nextcloud where the files actually live.
The full OnlyOffice Document Server install and Nextcloud integration, shown live step by step.
▶️ Watch Full VideoVendor documentation lists a few gigabytes as the floor, but comfortable real-world use starts higher, especially when Nextcloud shares the machine. Plan generous headroom and monitor actual usage — simultaneous editors are what consume memory.
Yes, and for small teams it is a sensible, common layout. The Document Server runs in its own Docker container with its own subdomain. The trade-off is shared resources: a busy editing session and a busy Nextcloud will compete for the same RAM and CPU.
No. Your files live in Nextcloud. The Document Server keeps a temporary cache of documents while they are being edited, plus its own settings and logs. Your document backup strategy stays centred on Nextcloud.