Commands for Copying File Systems

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When you want to copy or move individual files, portions of file systems, or complete file systems, you can use the procedures described in this chapter.

The following table describes various backup and restore commands that are available in the Oracle Solaris release. For enterprise environments, consider using a enterprise-level backup product. Information about enterprise-level backup products is available on the Oracle Technical Network.

Table 4-1 Summary of Various Backup Commands

Command Name	Aware of File System Boundaries?	Supports Multiple Volume Backups?	Physical or Logical Copy?
`volcopy`	Yes	Yes	Physical
`tar`	No	No	Logical
`cpio`	No	Yes	Logical
`pax`	Yes	Yes	Logical
`dd`	Yes	No	Physical
`zfs send and zfs receive`	Yes	N/A	Logical
`zfs snapshot`	Yes	N/A	Logical

The following table describes the advantages and disadvantages of some of these commands.

Table 4-2 Advantages and Disadvantages of tar, pax, and cpio Commands

Command	Function	Advantages	Disadvantages
`tar`	Use to copy files and directory subtrees to a single tape.	Available on most UNIX operating systems Public domain versions are readily available	Is not aware of file system boundaries Length of full path name cannot exceed 255 characters Cannot be used to create multiple tape volumes
`pax`	Use to copy files, special files, or file systems that require multiple tape volumes. Or, use when you want to copy files to and from POSIX-compliant systems.	Better portability than the `tar` or `cpio` commands for POSIX-compliant systems Multiple vendor support	Same disadvantages as the `tar` command, except that the `pax` command can create multiple tape volumes.
`cpio`	Use to copy files, special files, or file systems that require multiple tape volumes. Or, use when you want to copy files from systems running current Oracle Solaris releases systems to systems running older Solaris releases.	Packs data onto tape more efficiently than the `tar` command Skips over any bad spots in a tape when restoring Provides options for writing files with different header formats, such as ( `tar`, `ustar`, `crc`, `odc`, `bar`), for portability between different system types Creates multiple tape volumes	The command syntax is more difficult than the `tar` or `pax` commands.

The following sections describes step-by-step instructions and examples of how to use these commands.