Converting .crt to .pfx

Late answer but its still not now documented correctly i think (https://support.f5.com/csp/article/K31936122).
(edit LiefZimmerman to clarify the KB article was updated)

The problem is that the certificate files are stored as DER format and have to be converted to PEM format first while the key files already are in PEM format:

copy files:

cp /config/filestore/files_d/Common_d/certificate_d/:foo_1: /var/tmp/foo.der
cp /config/filestore/files_d/Common_d/certificate_key_d/:foo_2: /var/tmp/foo.key

check if DER:

openssl x509 -in /var/tmp/foo.der -inform DER -text

 if DER, convert to pem:

openssl x509 -inform DER -outform PEM -text -in /var/tmp/foo.der -out /var/tmp/foo.crt

create pfx:

openssl pkcs12 -export -out /var/tmp/foo.pfx -inkey /var/tmp/foo.key -in /var/tmp/foo.crt

remove files after exported pfx to another machine:

rm /var/tmp/foo.der
rm /var/tmp/foo.crt
rm /var/tmp/foo.key
rm /var/tmp/foo.pfx

greets

Irre