diff --git a/install_dehydrated.sh b/install_dehydrated.sh
index 80298d3..03faf19 100755
--- a/install_dehydrated.sh
+++ b/install_dehydrated.sh
@@ -2093,7 +2093,7 @@ if [[ -n "\$_successfully_created_hosts" ]] ; then
                   printf "_%s._tcp.%s. \$ttl_301 IN TLSA 3 0 1 %s\\n" \\
                      \${_tmp_arr[1]} \\
                      \${_tmp_arr[0]} \\
-                     \$(openssl x509 -in ${DH_BASE_DIR}/certs/\${_tmp_arr[0]}/cert.pem -noout -pubkey |
+                     \$(openssl x509 -in ${DH_BASE_DIR}/certs/\${_tmp_arr[0]}/cert.pem -outform DER |
                         openssl dgst -sha256 -binary |
                         hexdump -ve '/1 "%02x"')
                )