FeministWiki:Server setup

Revision as of 15:56, 23 February 2023 by Technician (talk | contribs)

These are the steps required to set up a new FeministWiki Debian or Ubuntu server. The guide assumes that you're comfortable connecting to a host with SSH and using the shell for various administration tasks, such as using systemctl, editing configuration files, installing packages, setting up SSH keys, and so on.

Initial setup of the new server

This section describes various initialization tasks for the new server that are independent of the old server.

Configure reverse DNS

In the settings of the VPS host (e.g. Strato AG), you can configure reverse-DNS for the IP address of the server. Set the FQDN for the IP address to feministwiki.org. It's good to do this early since it can take some time to propagate.

Make feministwiki.dev point to the new server

During setup and testing of the new server, we want to make it accessible under the feministwiki.dev domain. So change A entries of the feministwiki.dev DNS settings to point to the IP address of the new server.

Update & upgrade

First of all, let's make sure the system is up to date.

apt-get update
apt-get upgrade
apt-get dist-upgrade

Tighten security of SSH access

Port 22 will get lots of malicious login attempts. It's a good idea to change the SSH port, and also to disable password authentication in favor of key-based authentication. Both can be done by editing /etc/ssh/sshd_config.

Before restarting the SSH service, make sure you've actually added your public key (the contents of ~/.ssh/id_rsa.pub on your computer) to /root/.ssh/authorized_keys on the server, or you'll lock yourself out.

Some shell commands below reference the variable ${SSH_PORT}. This variable doesn't actually exist, unless you set it in your shell session. So either set the variable, or just replace it with the actual value of the SSH port you've configured.

Copy SSH key from old server

Copy over ~/.ssh/id_rsa and ~/.ssh/id_rsa.pub from the old server onto the new one. Make sure to set the permissions for the private key correctly: chmod 600 ~/.ssh/id_rsa

Set up firewall

For now, block everything but SSH.

apt-get install ufw
ufw allow proto tcp to 0.0.0.0/0 port ${SSH_PORT}
ufw enable

Install miscellaneous tools

Some of these are needed further down, some are just good to have.

apt-get install automysqlbackup \
                certbot \
                curl \
                dnsutils \
                emacs-nox \
                git \
                imagemagick \
                mg \
                moreutils \
                net-tools \
                nmap \
                rsync \
                software-properties-common \
                tree

Fetch scripts & config repo

Set up GitHub ssh access by copying the .ssh/id_rsa from the old server. After that:

cd ~
git clone git@github.com:FeministWiki/FeministWiki.git repo
cp -a repo/root/* repo/root/.??* .
sh repo/decrypt-pwd.sh

The decryption script will prompt you for a password the first time it's used. Enter the password stored in /root/pwd/meta on the old server.

Enable extra repositories

We might want to add some additional package repositories so we can use the latest version of some of the used software.

Backports is always OK to add since the packages don't get priority over the stable ones:

# Debian
echo deb http://deb.debian.org/debian $(lsb_release -sc)-backports main > /etc/apt/sources.list.d/backports.list

# Ubuntu
echo deb http://archive.ubuntu.com/ubuntu $(lsb_release -sc)-backports main universe > /etc/apt/sources.list.d/backports.list

PHP repo only if a very new version is needed:

wget -O /etc/apt/trusted.gpg.d/sury-php.gpg https://packages.sury.org/php/apt.gpg
echo "deb https://packages.sury.org/php/ $(lsb_release -sc) main" > /etc/apt/sources.list.d/sury-php.list

MariaDB repo only if a very new version is needed:

wget https://mariadb.org/mariadb_release_signing_key.asc
apt-key add mariadb_release_signing_key.asc
rm mariadb_release_signing_key.asc
echo "deb http://mirror.23media.de/mariadb/repo/10.4/debian $(lsb_release -sc) main" > /etc/apt/sources.list.d/mariadb.list

Create vmail user

groupadd -g 5000 vmail
useradd -u 5000 -g vmail -s /usr/sbin/nologin -d /home/vmail -m vmail

Install server components

Now we can install all the software used for the various FeministWiki services:

apt-get install apache2 \
                dovecot-core \
                dovecot-imapd \
                dovecot-ldap \
                dovecot-pop3d \
                ejabberd \
                fail2ban \
                inspircd \
                mailman \
                mariadb-server \
                opendkim \
                postfix \
                postfix-ldap \
                slapd

If any installation asks you for a password, remember that most passwords are found in /root/pwd.

Example for installing ejabberd from backports instead:

apt-get install ejabberd/$(lsb_release -sc)-backports # e.g. ejabberd/buster-backports

Install PHP and modules

This should really be part of the last section, but due to the sheer number of PHP modules we want to install, it's in its own section:

php_version=8.1 # or whatever version we're on

apt-get install php${php_version} \
                php${php_version}-apcu \
                php${php_version}-bcmath \
                php${php_version}-cli \
                php${php_version}-curl \
                php${php_version}-fpm \
                php${php_version}-gd \
                php${php_version}-gmp \
                php${php_version}-imagick \
                php${php_version}-intl \
                php${php_version}-ldap \
                php${php_version}-mbstring \
                php${php_version}-mysql \
                php${php_version}-opcache \
                php${php_version}-readline \
                php${php_version}-xml \
                php${php_version}-zip

Copy over certificates

Copy over the certs from the old server:

tar -czPf- /etc/fw-certs | ssh feministwiki.dev -p ${SSH_PORT} 'tar -xzf-'

The /etc/fw-certs directory is owned by the group ssl-cert, and files that contain the private key can only be read by group members. To allow certain services to read those files, add them to the group:

adduser ejabberd ssl-cert
adduser irc ssl-cert

Put config files in place

The principle is simple: take all the config files from /root/repo/etc and put them where they belong in /etc. However, since a new server might mean much newer software, it's possible that some config files aren't compatible anymore, or that some new sensible defaults might be overwritten by the old config. Sadly figuring out these incompatibilities is a manual process: compare the new default config with the old default config and to our current config, to figure out what our new config should look like.

There's a number of things important to remember however:

  • Don't forget to revert the redactions of sensitive information. Search files for [REDACTED].
  • After copying in the new /etc/aliases file, run newaliases for the changes to take effect.
  • After copying something into /etc/apache2/conf-available, don't forget to enable it via a2enconf.
  • After populating /etc/letsencrypt/renewal-hooks, remember to chmod +x all the scripts.
  • Likewise, don't forget chmod +x for /etc/cron.{hourly,daily,weekly,monthly} and /etc/boot.d.

Apache modules, config, and sites

Enable PHP FPM:

a2enmod proxy_fcgi
a2enconf php${php_version}-fpm

We need a number of Apache modules to be enabled which might not be enabled by default:

a2enmod expires headers macro rewrite ssl
a2enconf 99-local
a2ensite fw-account fw-blogs fw-chat fw-files fw-forum fw-mail fw-wiki fw-xmpp

Copying over live data

We want to make a first run of this copy process purely for testing purposes. Note that although some of the steps described in this section take a long time to finish, they can be done in parallel.

Some of the commands here assume that you've set up ssh access from the old server into the new server. For this to work, copy the contents of /root/.ssh/id_rsa.pub on the old server, and append them as an additional line onto /root/.ssh/authorized_keys on the new server.

LDAP databases

Stop the LDAP server and delete the existing configuration and data on the new server (careful!):

# Commands to run on the NEW (fresh) server:
systemctl stop slapd
rm -r /etc/ldap/slapd.d/*
rm /var/lib/ldap/data.mdb

Then copy over the config and data by running these commands from the old server:

slapcat -n 0 | ssh feministwiki.dev -p ${SSH_PORT} 'sudo -u openldap slapadd -n 0 -F /etc/ldap/slapd.d'
slapcat -n 1 | ssh feministwiki.dev -p ${SSH_PORT} 'sudo -u openldap slapadd -n 1'

Breaking changes in OpenLDAP

There might be incompatible changes between OpenLDAP (aka slapd) versions which require manual editing of the slapcat output before it's read in on the new server with slapadd.

Here's one example that occurs when updating from OpenLDAP 2.4.42 or earlier to 2.4.43 or later: the ppolicy overlay has a new attribute in the newer version, so if you simply run the commands above, the first one (the one that copies the config database) will produce the following error message:

User Schema load failed for attribute "pwdMaxRecordedFailure". Error code 17: attribute type undefined

The solution is as follows:

  1. On the new server, open /etc/ldap/schema/ppolicy.ldif and search for pwdMaxRecordedFailure. You will note that there is a olcAttributeTypes: ... entry that defines it, and also it's listed in the MAY attributes block of the olcObjectClasses: ... entry that defines the pwdPolicy object class.
  2. On the old server, save the output of slapcat -n 0 to a file, open the file, and search for the block where the ppolicy schema is defined. It should start with the line dn: cn={4}ppolicy,cn=schema,cn=config (the {4} part might contain a different integer, that's OK). There, note that the olcAttributeTypes: ... entry for pwdMaxRecordedFailure is missing, and also it's not listed in the MAY list of the pwdPolicy object class definition. Copy over the attribute type definition from the ppolicy.ldif file on the new server, and amend the MAY list to include it.

The above is explained only for instructive purposes, since this particular fix will already have been applied by the time someone reads this guide. It's meant to give you an idea as to how backwards incompatible changes in OpenLDAP schema files can be amended when migrating to a newer version. (Also, no such clear explanation of the fix seems to be found anywhere on the web, so maybe someone who searches the error message above will come upon this guide and be happy!)

Contents of /var/www

This is very simple but takes a lot of time to finish. Run it from the old server:

rsync -e "ssh -p ${SSH_PORT}" -az --delete /var/www/ root@feministwiki.dev:/var/www

Note that the trailing slash in /var/www/ is important; if not provided, it will copy the directory to /var/www/www on the new server.

SQL databases

Run the following command from the old server:

mysqldump -u root -p"$(cat /root/pwd/mysql)" \
  --add-drop-database \
  --databases blogs \
              feministfiles \
              feministforum \
              feministmail \
              feministwiki \
              feministwiki_de \
              feministwiki_es \
              feministwiki_fr \
              feministwiki_it \
              feministwiki_pt \
              fff \
  | gzip | ssh root@feministwiki.dev -p ${SSH_PORT} 'gunzip | /root/bin/sql'

You can use the show databases; command in the SQL console to make sure that the list of databases is complete. Unfortunately they have to be listed manually, because using the --all-databases option includes system databases that we don't want to copy.

Emails

This is a simple one. Run this command from the old server:

rsync -e "ssh -p ${SSH_PORT}" -az --delete /home/vmail/ root@feministwiki.dev:/home/vmail

Note that the trailing slash in /home/vmail/ is important.

Mailman data

GNU Mailman uses a filesystem-based "database" so we can transfer over its data as follows; run this from the old server:

cd /var/lib/mailman
rsync -e "ssh -p ${SSH_PORT}" -az --delete archives data lists root@feministwiki.dev:/var/lib/mailman

And then this on the new server:

check_perms -f

The check_perms command, which is part of GNU Mailman, will take care of fixing file ownership and permissions.

Recreate SQL users

If the versions of MariaDB on the old and new server are compatible enough, you might be able to dump the mysql.user table and import it on the new server, but it's safer to recreate the users from scratch. To do so, run this on the new server:

/root/bin/sql << EOF
create user blogs@localhost identified by '$(cat ~/pwd/mysql-blogs)';
create user feministfiles@localhost identified by '$(cat ~/pwd/mysql-files)';
create user feministforum@localhost identified by '$(cat ~/pwd/mysql-forum)';
create user feministmail@localhost identified by '$(cat ~/pwd/mysql-mail)';
create user feministwiki@localhost identified by '$(cat ~/pwd/mysql-wiki)';
create user fff@localhost identified by '$(cat ~/pwd/mysql-fff)';
EOF

Now grant them access to their corresponding databases. Remember that this has to be done after the databases have been copied over:

/root/bin/sql << EOF
grant all on blogs.* to blogs@localhost;
grant all on feministfiles.* to feministfiles@localhost;
grant all on feministforum.* to feministforum@localhost;
grant all on feministmail.* to feministmail@localhost;
grant all on feministwiki.* to feministwiki@localhost;
grant all on feministwiki_de.* to feministwiki@localhost;
grant all on feministwiki_es.* to feministwiki@localhost;
grant all on feministwiki_fr.* to feministwiki@localhost;
grant all on feministwiki_it.* to feministwiki@localhost;
grant all on feministwiki_pt.* to feministwiki@localhost;
grant all on fff.* to fff@localhost;
EOF

Test

It's important to test the new server to make sure everything works well!

Reboot

We could restart a lot of services manually to ensure they've read their new config, but it's easiest to just reboot. (The new server, obviously.)

Open ports

We need to open all the ports used by the various FeministWiki services:

for port in 25 80 443 465 587 993 995 5222 5223 5269 5270 5443 6697 7777
do ufw allow proto tcp to 0.0.0.0/0 port $port
done

Test!

At this point you should test everything using the feministwiki.dev domain name.

Some things may not work correctly because they're hard-coded to work as "feministwiki.org" and not under the "feministwiki.dev" name. Here's a list of known issues related to this:

  • WordPress normally redirects clients to the canonical address of a blog if it's visited through an alternative domain name. This means we get redirected back to the old server if we try to visit blogs.feministwiki.dev. To work around this, we use RequestHeader set Host in the Apache2 site configuration, which fools WordPress into believing it's being accessed through the canonical domain name. Still, the HTML/CSS/JS sent back to the browser refers to some resources on the .org domain, which then fail to load due to CORS violation.

If you want to be extra thorough, you can edit your /etc/hosts file to make feministwiki.org, various *.feministwiki.org subdomains, and maybe even other aliases (such as fem.wiki) point to the new server, and then test the few stubborn services that won't otherwise play nice.

Deactivate again

After we're done testing, we can "deactivate" the new server again to prepare it for the final switch-over:

for port in 25 80 443 465 587 993 995 5222 5223 5269 5270 5443 6697 7777
do ufw delete allow proto tcp to 0.0.0.0/0 port $port
done

systemctl stop apache2
systemctl stop dovecot
systemctl stop ejabberd
systemctl stop inspircd
systemctl stop mailman
systemctl stop postfix
systemctl stop slapd

Finishing up

Now, all services on the old server should be stopped, because we will begin the final transfer of live data.

Stop services on the old server

Stop all the services that interface with users and/or are responsible for modifying live data:

systemctl stop apache2
systemctl stop dovecot
systemctl stop ejabberd
systemctl stop inspircd
systemctl stop mailman
systemctl stop postfix
systemctl stop slapd

Close all the relevant ports just to be double-sure:

for port in 25 80 443 465 587 993 995 5222 5223 5269 5270 5443 6697 7777
do ufw delete allow proto tcp to 0.0.0.0/0 port $port
done

Copy over the live data one more time

Simply repeat the whole section Copying over live data.

The techniques and commands described above in the section Copying over live data are idempotent, meaning you can simply repeat them and they will make sure that the new copy of the live data is fresh and doesn't leave any outdated data on the new server. For instance, the --delete argument to the rsync command and the --add-drop-database argument to the mysqldump command help to make sure of this.

So just repeat the steps from that section exactly one more time.

Reboot the new server

At this point we can reboot the new server again, to make sure all services are properly restarted.

Open ports on the new server

Now we can open the ports again on the new server:

for port in 25 80 443 465 587 993 995 5222 5223 5269 5270 5443 6697 7777
do ufw allow proto tcp to 0.0.0.0/0 port $port
done

Update DNS entries

You have to change the configuration of the following domains:

  • feministwiki.org
  • feministwiki.net
  • feministwiki.de
  • fem.wiki
  • feminism.wiki
  • feminist.wiki
  • fffrauen.de

feministwiki.org

You only have to change three DNS entries, since most of the subdomains work via CNAME entries:

  • The main A entry for @ (self-reference i.e. feministwiki.org)
  • The A entry for smtp since this is not allowed to be a CNAME
  • The A entry for xmpp since this is not allowed to be a CNAME

Other domains

For these, you only have to change the main A entry, since they don't use SMTP or XMPP.

Configure LetsEncrypt

Since we changed the DNS settings, we can now set up certbot:

certbot register -n --agree-tos -m technician@feministwiki.org
letsencrypt-refresh

Finishing up

At this point, everything should be functional. If not, it's time for some debugging!