密码策略
vi /etc/login.defs
PASS_MAX_DAYS 60
PASS_MIN_DAYS 3
PASS_MIN_LEN 8
PASS_WARN_AGE 7
vi /etc/pam.d/system-auth
minlen=12 lcredit=-1 ucredit=-1 dcredit=-1 ocredit=-1 enforce_for_root
authconfig --passminlen=12 --update
authconfig --passmaxclassrepeat=4 --update
authconfig --enablereqlower --update
authconfig --enablerequpper --update
authconfig --enablereqdigit --update
authconfig --enablereqother --update
vi /etc/security/pwquality.conf
maxsequence = 4
difok = 6
authconfig --test | grep hashing
authconfig --passalgo=sha512 --update
authconfig --test | grep hashing
vi /etc/pam.d/sshd
auth required pam_tally2.so onerr=fail deny=3 unlock_time=300 even_deny_root root_unlock_time=300
