Translation will be done soon.

First install Ubuntu Server.
Next add openssh-server
Next install Docker:

curl -sSL https://get.docker.com/ | sh

Verify docker is installed and ok:

sudo docker run hello-world

if everything is okay proceed to installation of OnlyOffice: DocumentServer MailServer CommunityServer

Installing Document Server:

sudo docker run -i -t -d --name oo-doc onlyoffice/documentserver

where oo-doc is choosed name for the container
Same procedure for the Mail Server (this step can be skipped):

sudo docker run --privileged -i -t -d --name oo-mail -p 25:25 -p 143:143 -p 587:587 -h oo.feoschool12.edu.ru onlyoffice/mailserver

And Community Server:

sudo docker run -i -t -d -p 80:80 -p 443:443 --name oo-comm --link oo-mail:mail_server --link oo-doc:document_server onlyoffice/communityserver

Actually, Mail Server installation can be skipped so Community Server installtion may look like:

sudo docker run -i -t -d -p 80:80 -p 443:443 --name oo-comm --link oo-doc:document_server onlyoffice/communityserver

When you want to stop the servers use the following commands (based on the container names above):
sudo docker stop oo-comm
sudo docker stop oo-doc
sudo docker stop oo-mail

To start them again you need to start the linked servers first (before the community server) as follows:

sudo docker start oo-mail
sudo docker start oo-doc
sudo docker start oo-comm