DES Weak Keys - Double Encryption
If you don't get the expected result, then you are doing it wrong; most probably, use wrong mode of operation and/or wrong padding. You can get the expected result with openssl as

openssl enc -e -des-ecb -in plain.txt -out cipher1.txt -nopad -K 0101010101010101 -iv 0
openssl enc -e -des-ecb -in cipher1.txt -out cipher2.txt -nopad -K 0101010101010101 -iv 0


plain.txt file size should be multiple of 8 (8 bytes is DES block size), and plain.txt and cipher2.txt files should be identical.