1. 修改 安装目录/redmin/apps/redmine/htdocs/config/database.yml，更对对应的用户名，密码，数据库地址，端口号
production:
adapter: mysql2
database: bitnami_redmine
host: 127.0.0.1
username: root
password: ""
port: 3307
encoding: utf8
socket: /home/hyadmin/redmin/mysql/tmp/mysql.sock
development:
adapter: mysql2
database: redmine_development
host: localhost
username: root
password: ""
encoding: utf8
# Warning: The database defined as "test" will be erased and
# re-generated from your development database when you run "rake".
# Do not set this db to the same as development or production.
test:
adapter: mysql2
database: redmine_test
host: localhost
username: root
password: ""
encoding: utf8
2. 进入如下目录
cd 安装目录/redmin/apps/redmine/htdocs/script
3. 执行如下命令，进入ruby
./rails console production
4. 取得你要修改的用户对象(ruby>代表进入ruby环境）
ruby>admin_user = User.find_by_login('你要改的用户名')
5.修改admin用户对象密码
ruby>admin_user.password = '你的密码'
注: 这个密码不能太短，否则报错。
6.保存admin用户对象信息
ruby>admin_user.save!
7.退出ruby环境
ruby>quit
这样应该就可以用yourpassword这个新密码登录系统了
通常已被加密的字符串，是无法逆向解出原始字串出来。只能用另一字符串的加密后的结果来比对是不是相同的结果，
来得知密码对不对：
>>p1 = "helo".crypt(*kk*)
=>"kkILjMeWfFdKc"
>>p1 == "what".crypt(*kk*)
=>false
>>p1 == "helo".crypt(*kk*)
=>true
