Server/horror/Technical documentation

Pagina legata al server ⚙️ horror

Public technical documentation for the server ⚙️ horror, dedicated to off-site backups.

Server access

Server administrators can be authorized to enter with a dedicated account using SSH.

You need

A good reason.

Instructions

ssh name-surname@horror.wikimedia.it

Be sure to be authorized before trying. Do not try random attempts or you will be blocked.

Request access policy:

• https://wiki.wikimedia.it/wiki/Infrastruttura

Overview

A system administrator with #Server access and enough privileges can login in the server via SSH.

You need

sysadmin experience with GNU/Linux.

Instructions

All recent backups are here:

/var/backups/wmi

Older copies can be obtained adding a numeric suffix. For example the 2-days-old backups are here:

/var/backups/wmi.2

Note that all sub-directories can be accessed only if you are its dedicated user.

For example all of these are owned by the user lessema:

/var/backups/wmi/lessema.wikimedia.it
/var/backups/wmi.1/lessema.wikimedia.it
/var/backups/wmi.2/lessema.wikimedia.it
/var/backups/wmi.3/lessema.wikimedia.it

So to get these copies do something like this:

rsync lessema@horror.wikimedia.it:/var/backups/wmi/lessema.wikimedia.it .

If it does not work, make sure to have the right #Server access privileges.

Filesystem policies

Here is a summary of the main filesystem pathnames

Path	owner:group	Permissions	Description
/var/backups/wmi	root:root	755	Everyone should be allowed to list its sub-directories to list the available latest backups. Note: You may be allowed to list sub-directories but you are not allowed to access them as default.
/var/backups/wmi.*	root:root	750	Everyone should be allowed to list its sub-directories to know the available old backups. Note: You may be allowed to list sub-directories but you are not allowed to access them as default.
/var/backups/wmi/project	project:project	750	The user project must be the only one allowed to access in its sub-directory.

Add a project under the backup umbrella

You need

• a GNU/Linux server (foo) with some files to be saved
• SSH access to server foo
• SSH access to server ⚙️ horror (#Server access) and sudo
• knowledge of SSH keys
• knowledge of data transfers over SSH (e.g. using rsync)

Instructions

In short you just need to create a directory on server ⚙️ horror and a dedicated user able to read/write in that directory. Then, you can push backups on that directory.

Some pseudo-instructions to be executed from server ⚙️ horror to create a new project foo to be added under its backup umbrella:

USERNAME=foo
PROJECT=foo.wikimedia.it

sudo adduser --disabled-password $USERNAME

sudo mkdir --parents           /var/backups/wmi/"$PROJECT"
sudo chown $USERNAME:$USERNAME /var/backups/wmi/"$PROJECT"

The final purpose is to execute this command daily from you server foo:

rsync /my/important/pathname foo@horror.wikimedia.it:/var/backups/wmi/foo.wikimedia.it

For example using a crontab.

It's that simple.

If want to have don't want to manually run an rsync to push backups but you want some syntax sugar or you want to also do dumps or start/stop services, here some useful backup scripts which can be used to make on-site backups, and then send the copy to server ⚙️ horror:

• https://gitpull.it/source/micro-backup-script/
• ...