linux 6种随机数产生

1 echo $RANDOM

echo $RANDOM | md5sum | cut -c 1-9 (截取8位)

2 openssl rand -base64 8
openssl rand -base64 8 | md5sum | cut -c 1-9

3 date +%N%t
echo "$(date +%N%t)"

4 mkpasswd -l 8
mkpasswd -l 8 | md5sum (需 rpm -qa expect)

5 head /dev/urandom | cksum

6 cat /proc/sys/kernel/random/uuid
cat /proc/sys/kernel/random/uuid | md5sum | cut -c 1-9

将随机数排序且去重

echo $RANDOM | md5sum | cut -c 1-9 | sort | uniq -c | sort -nk1 (最前面数字为1即惟一)

20个：
for n in `seq 20`;do echo $RANDOM |md5sum|cut -c 1-9|sort|uniq -c|sort -nk1;done