I try to create a Certificate Signing Request (CSR) using
openssl req -new -sha256 -key domain.key -subj "/" \ -reqexts SAN -config <(cat /System/Library/OpenSSL/openssl.cnf \ <(printf "[SAN]\nsubjectAltName=DNS:foo.com,DNS:www.foo.com"))
but getting the following error message on my macbook
cat: /dev/fd/63: No such file or directory
unknown option -reqexts
Any ideas?
Your command is probably copy&paste of a multi-line command where backslashes are used to join lines, however you somehow managed to get newlines converted to spaces.
Remove all occurences of "backslash + space".