Network Administration

Network Backup Daemon

Apunix Computer Services

NBD consists of a SCSI driver for one of our three brands of helical-scan tape drives (Exabyte, HP DAT, and WangDat) and two main utilities: mdump and far.

NBD's mdump backs up a network of UNIX-based machines to a single high-density tape. It writes in a non-proprietary format, so standard UNIX recovery tools like ufsrestore can be used. However, it adds an index file to the beginning of the tape to simply restores; monitors dump output for errors or clients that are not reachable on the network; and sends mail to the system administrator in the event of any unexpected difficulty, thus allowing multiple backups to occur on unattended systems.

far writes data in a tar-compatible format, but also uses an index file to speed retrieval using the Quick File Access (QFA) feature of helical-scan tape drives, allowing lightning-fast extraction, 20-200 times faster than from regular tar archives.