接到中心电邮，去西红门营业厅配合操作Oracle备份与netbackup策略设定（将Oracle导出数据用nbu进行备份到磁带中）期间有一个小的注意点需要指出，防止大家跟我一样忽略平时不经常用的一些参数。
下面是在oracle 10g下使用exp导出用户下面所有对象跟表
exp user/pwd file=/dir/xxx.dmp log=xxx.log owner=zh
...................................................
注意红色标注处，原先我并没有勾选此选项，看下一个图
设定了一个全备策略，并且制定失效时间两年
客户端的选择与要备份的目录
我在监视器中查看当前备份的任务计划，发现
发现有报错信息：/ssbak is on file system type NFS.Skipping
这时候查看关于NFS在nbu中的设定，我发现有一个参数follow nfs。而且在赛门铁克官网有一个这样的说明：
- NFS files or directories, unless you set Follow NFS. These files are likely backed up by the home host.
- Files or directories in a different file system if you do not set Cross Mount Points or include those mount points in
- Files or directories with path lengths longer than 1023 characters.
- Files or directories where the operating system does not return inode information (the lstat system call failed).
- Directories that NetBackup cannot access (cannot use the cd command to access).
- On a disk managed by Storage Migrator, migrated files or directories where Storage Migrator does not return inode information (mig_stat fails). Note that NetBackup Server does not support Storage Migrator.
- Socket special files (named pipes are backed up).
- Door files
- Locked files when mandatory locking is enabled by an application that currently has the file open.
- Busy files. If a file is open, NetBackup backs up the last saved version of the file.
NetBackup automatically excludes the following file system types on most platforms:
- cdrom (all UNIX/Linux platforms)
- cachefs (AIX, Solaris, SGI, UnixWare)
- devpts (Linux)
- mntfs (Solaris)
- proc (UNIX/Linux platforms; does not exclude automatically for AIX, so /proc must be added manually to exclude list. If not added manually, partially successful backups may result when using the ALL_LOCAL_DRIVES directive on AIX)
- tmpfs (Linux)
- usbdevfs
然而选项follow NFS与Cross mount point参数定义
Follow NFS
指定是否备份NFS的文件系统（远程在本地安装的文件系统）
Cross Mount Point（交叉文件系统）
在UNIX系统中，每一个文件系统都有一个Mount点，这个Mount点可能位于整个系统的任意位置。当一个文件系统的Mount点位于另一个文件系统之下时，我们称之为交叉文件系统。如：/文件系统包括/usr和/tmp的子文件系统。
所以将此两个选项勾选，备份成功！
本文转自yangjunfeng 51CTO博客，原文链接:http://blog.51cto.com/yangjunfeng/998276
