在Ubutun 8.10 64bit server上安装了DB2 Express-C v9.5.2，将Mars服务端程序移植过去，却发现数据库怎么也连不上，出错信息如下：
ERROR:
SQL30082N Security processing failed with reason "15" ("PROCESSING FAILURE"). SQLSTATE=08001
折腾了半个小时，发现用实例拥有者db2inst1用户登录，连接数据库时将密码和用户名置空就可以成功连接，真是奇了怪了。
刚才在IBM的论坛里找到了答案（http://www.ibm.com/developerworks/forums/thread.jspa?messageID=14174958）
tamers网友提出的解决办法：
I had the same problem on Ubuntu v8.10. I replaced the following line in /etc/pam.d/common-password password success=1 default=ignore pam_unix.so obscure sha512with the line below:
password success=1 default=ignore pam_unix.so obscure md5 then, reset the passwords of the db2 users using "passwd" command. and the problem solved.
Thanks for the clue above.
STEP1 将/etc/pam.d/common-password文件中下面这行：
password success=1 default=ignore pam_unix.so obscure sha512
替换成：
password success=1 default=ignore pam_unix.so obscure md5
STEP2
在SHELL中运行 passwd命令更改密码。
OK！
为什么要这样做，_mihai_一语道破天机：
I am referring to the one the operating system is using to compute the hash for the password.
It is very likely producing a hash that is bigger than what DB2 supports and that is why you are seeing the error.
操作系统对密码采取了不同的HASH算法，很可能HASH后的密码串长度超过了DB2支持的最长密码长度。
所以，_mihai_的建议是：
You are likely using sha512, change it to sha256 or md5, it should work fine.
将sha512的HASH算法改为sha256或者md5算法。