FeministWiki

FeministWiki:Server setup

Revision as of 20:16, 24 February 2023 by Technician (talk | contribs) (→‎Put config files in place)
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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.

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 SSH access from the old server

Some of the commands further below need SSH access from the old server to the new server, using the feministwiki.dev domain name. Since we've just copied over the public key of the old server, we can enable access from the old server with this simple command: 

# Run on new server
cat .ssh/id_rsa.pub >> .ssh/authorized_keys

Further, to make our life easier, we can edit the SSH configuration on the old server so we don't have to manually specify the custom SSH port number every time. Add a block like the following into ~/.ssh/config on the old server, replacing <SSH_PORT> with the actual port number: 

Host feministwiki.dev
    Port <SSH_PORT>

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} # Replace with actual port number
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 'tar -xzPf-'

The /etc/fw-certs directory and its contents should be owned by the group ssl-cert. Make sure this is the case on the new server after running the command above, since the group ID might be different on the new server. If the group doesn't exist at all, just create it.

Further, files in that directory which contain the private key (privkey.pem and bundle.pem) should only be readable by group members. That is, their permission mode should be 640, displayed as -rw-r----- in the output of ls -l. Make sure this really the case.

Then, to allow certain services to read those files containing the private key, add them to the ssl-cert 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/or with our own config saved in the repo, to figure out what our new config files should look like.

There's a number of things important to remember:

  • Don't forget to revert the redactions of sensitive information. Search files for [REDACTED].
  • After copying over the Postfix configuration, run newaliases to create the alias database files.
  • You may also have to run postmap on some files, like /etc/postfix/sender_access.
  • 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 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

OpenLDAP configuration database

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

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

Then copy over the configuration database, by running the following commands from the old server: 

slapcat -n 0 | ssh feministwiki.dev 'sudo -u openldap slapadd -n 0 -F /etc/ldap/slapd.d'

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. Following are two examples of this.

These particular issues won't apply anymore when you're reading this guide, since they are one-time issues related to migrating to a newer OpenLDAP version, but they serve as good examples. (Also, no such clear explanation of the first problem seems to be found anywhere on the web, so maybe someone who searches the related error message below will come upon this guide and be happy!)

OpenLDAP Migration: Example Problem 1

This problem occurs when migrating from OpenLDAP 2.4.42 or earlier, to 2.4.43 or later.

The ppolicy overlay gained a new attribute in OpenLDAP version 2.4.43, so if you simply run the command above which copies over the configuration database onto the new server, it 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 see an olcAttributeTypes: ... entry that defines it. 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 it in a text editor, 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.
OpenLDAP Migration: Example Problem 2

This problem occurs when migrating to OpenLDAP 2.5, and although the change is bigger, the fix is easier. The issue is actually documented in the OpenLDAP 2.5 Administrator's Guide, Appendix B.2:

https://www.openldap.org/doc/admin25/appendix-upgrading.html

The second paragraph tells us what to do:

In OpenLDAP 2.4 the slapo-ppolicy(5) overlay relied on a separate schema file to be included for it to function. This schema is now implemented internally in the slapo-ppolicy module. When upgrading slapd.conf(5) deployments the include statement for the schema must be removed. For slapd-config(5) deployments, the config database must be exported via slapcat and the old ppolicy schema removed from the export. The resulting config database can then be imported.

In simpler terms:

  1. Save the output of slapcat -n 0 from the old server in a file: 
    slapcat -n 0 > slapcat.n0.out
  2. Open the file in a text editor and delete the block starting with the line dn: cn={4}ppolicy,cn=schema,cn=config, up to the next empty line (before the next block starting with a dn: ... line), and save the file.
  3. Feed the file to slapadd -n 1 on the new server: 
    cat slapcat.n0.out | ssh feministwiki.dev 'sudo -u openldap slapadd -n 0 -F /etc/ldap/slapd.d'

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.

LDAP database

Delete the existing database on the new server (careful!): 

rm /var/lib/ldap/data.mdb

Then copy over the database by running the following command from the old server: 

slapcat -n 1 | ssh feministwiki.dev 'sudo -u openldap slapadd -n 1'

Although there may be breaking changes that make this command fail, just as with the copying of the configuration database explained earlier, the chance is much lower for the regular "data" database, so hopefully the command will run fine.

Contents of /var/www

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

rsync -az --delete /var/www/ 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 '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 -az --delete /home/vmail/ 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 -az --delete archives data lists 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!

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