Chapter 10. Filesystems and Disks

Managing Unix filesystems is one of the system administrator's most importanttasks. You are responsible for ensuring that users have access to the files they need and that these files remain uncorrupted and secure. Administering afilesystem includes tasks such as:

• Making local and remote files available to users

• Monitoring and managing the system's disk resources

• Protecting against file corruption, hardware failures, and user errors via a well-planned backup schedule

• Ensuring data confidentiality by limiting file and system access

• Checking for and correcting filesystem corruption

• Connecting and configuring new storage devices when needed

Some of these tasks—such as checking for and correcting filesystem corruption—are usually done automatically at boot time, as part of the initial system startup. Others—like monitoring disk space usage and backups—are often done manually, on a periodic or as-needed basis.

This chapter describes how Unix handles disks and filesystems. It covers such topics as mounting and dismounting local and remote filesystems, the filesystem configuration file, making local filesystems available to remote Unix and Windows users, checking local filesystem integrity with the fsck utility, and adding new disks to the system. It also looks at some optional filesystem features offered in some Unix implementations.

We looked at file ownership and protection in Section 2.1. This chapter considers filesystem protection for network shared filesystems. Other related topics considered elsewhere in this book include the discussions in Chapter 15 of managing disk space with disk quotas (Section 15.6), disk I/O performance (Section 15.5), and planning for swap space (Section 15.4), and the discussion of planning and performing backups in Chapter 11.