Vor einem Update von WordPress wollte ich wie gewohnt meine Datenbank sichern:

# mysqldump -u username -p wordpress > wordpress.sql
# mysql -u username -p wordpress_bu_20191113 < wordpress.sql

Leider brach der Import mit der Fehlermeldung "ERROR 1118 (42000) at line 2239: Row size too large (> 8126). Changing some columns to TEXT or BLOB may help. In current row format, BLOB prefix of 0 bytes is stored inline." ab.
Nach kurzer Recherche entschied ich mich für folgenden Workaround:
Setzen der Variable innodb_strict_mode auf OFF in der Datei /etc/mysql/mariadb.conf.d/50-server.cnf:

…
# This group is only read by MariaDB servers, not by MySQL.
# If you use the same .cnf file for MySQL and MariaDB,
# you can put MariaDB-only options here
[mariadb]
# Rana
# Kommentarzeichen entfernen wenn der Fehler
# "ERROR 1118 (42000) at line 2239: Row size too large (> 8126). Changing some columns to TEXT or BLOB may help. In
# current row format, BLOB prefix of 0 bytes is stored inline." auftritt:
#
innodb_strict_mode=OFF

Nach der Änderung nicht auf den Neustart der Datenbank-Daemon vergessen!

# systemctl restart mysqld.service

Danach funktionierte der Import ohne Probleme.
Ich habe nach dem Import die Variable in der Konfigurationsdatei /etc/mysql/mariadb.conf.d/50-server.cnf wieder auskommentiert und den Daemon neu gestartet.
Weitere Infos zu dem Thema sind in der Knowledgebase zu MariaDB unter Troubleshooting Row Size Too Large Errors with InnoDB zu finden.

Erzeugen neuer Zertifikate

Installation von certbot

# apt-get install python-certbot-apache

Erzeugen der Zertifikate

# /etc/letsencrypt/live# sudo certbot certonly --manual -d *.rana.at --agree-tos --no-bootstrap --manual-public-ip-logging-ok --preferred-challenges dns-01 --server https://acme-v02.api.letsencrypt.org/directory
Saving debug log to /var/log/letsencrypt/letsencrypt.log
Plugins selected: Authenticator manual, Installer None
Obtaining a new certificate
Performing the following challenges:
dns-01 challenge for rana.at

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Please deploy a DNS TXT record under the name
_acme-challenge.rana.at with the following value:

dfpLiD95pF30KpwyBt_E1nnpjQy5mjJbUZIuqW7nF1s

Before continuing, verify the record is deployed.
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Press Enter to Continue
Waiting for verification...
Cleaning up challenges

IMPORTANT NOTES:
 - Congratulations! Your certificate and chain have been saved at:
   /etc/letsencrypt/live/rana.at/fullchain.pem
   Your key file has been saved at:
   /etc/letsencrypt/live/rana.at/privkey.pem
   Your cert will expire on 2020-05-26. To obtain a new or tweaked
   version of this certificate in the future, simply run certbot
   again. To non-interactively renew *all* of your certificates, run
   "certbot renew"
 - If you like Certbot, please consider supporting our work by:

   Donating to ISRG / Let's Encrypt:   https://letsencrypt.org/donate
   Donating to EFF:                    https://eff.org/donate-le

Die aktuellen Zertifikate sind im Verzeichnis /etc/letsencrypt/live/rana.at/ zu finden.

Apache-Konfiguration

/etc/apache2/sites-available/rana.at.conf:

…
    SSLEngine On
    SSLCertificateFile /etc/letsencrypt/live/rana.at/fullchain.pem
    SSLCertificateKeyFile /etc/letsencrypt/live/rana.at/privkey.pem

Update des Zertifikate

# certbot certonly --server https://acme-v02.api.letsencrypt.org/directory --manual --preferred-challenges dns -d 'example.org'
Saving debug log to /var/log/letsencrypt/letsencrypt.log
Plugins selected: Authenticator manual, Installer None
Obtaining a new certificate
Performing the following challenges:
dns-01 challenge for example.org

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
NOTE: The IP of this machine will be publicly logged as having requested this
certificate. If you're running certbot in manual mode on a machine that is not
your server, please ensure you're okay with that.

Are you OK with your IP being logged?
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
(Y)es/(N)o: Y

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Please deploy a DNS TXT record under the name
_acme-challenge.example.org with the following value:

sadkljfs87q80493rdsn.kadlsf89aeduicasiodfuap

Before continuing, verify the record is deployed.
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Press Enter to Continue
Waiting for verification...
Cleaning up challenges

IMPORTANT NOTES:
 - Congratulations! Your certificate and chain have been saved at:
   /etc/letsencrypt/live/example.org-0001/fullchain.pem
   Your key file has been saved at:
   /etc/letsencrypt/live/example.org-0001/privkey.pem
   Your cert will expire on 2020-02-04. To obtain a new or tweaked
   version of this certificate in the future, simply run certbot
   again. To non-interactively renew *all* of your certificates, run
   "certbot renew"
 - If you like Certbot, please consider supporting our work by:

   Donating to ISRG / Let's Encrypt:   https://letsencrypt.org/donate
   Donating to EFF:                    https://eff.org/donate-le

Wöhrend der Ausführung nach dem ersten Y den TXT-Record nach Aufforderung anpassen und die DNS-Zonendatei neu laden!