Générer un CSR

openssl req -newkey rsa:2048 -subj /CN=example.com -nodes -keyout example.com.key -out example.com.csr

ou

CN="domain.tld"
FILE=cert-domain.tld
openssl req -newkey rsa:2048 -subj /CN=$CN -nodes -keyout $FILE.key -out $FILE.csr

CN="domain.tld"
FILE=cert-domain.tld
STATE=Val de Marne
VILLE=Joinville-le-Pont
PAYS=FR
ORGA=My Company
ORGA_UNIT=Service Informatique
openssl req -new -newkey rsa:2048 -nodes -out $FILE.csr -keyout $FILE.key -subj "/C=$PAYS/ST=$STATE/L=$VILLE/O=$ORGA/OU=$ORGA_UNIT/CN=$CN"