Veritas Storage Foundation 5.1 SP1 Cluster File System Administrator"s Guide (5900-1738, April 2011)

ACL (access control list) The information that identifies specific users or groups and their access privileges
for a particular file or directory.
agent A process that manages predefined Veritas Cluster Server (VCS) resource types.
Agents bring resources online, take resources offline, and monitor resources to
report any state changes to VCS. When an agent is started, it obtains configuration
information from VCS and periodically monitors the resources and updates VCS
with the resource status.
allocation unit A group of consecutive blocks on a file system that contain resource summaries,
free resource maps, and data blocks. Allocation units also contain copies of the
super-block.
API Application Programming Interface.
asynchronous writes A delayed write in which the data is written to a page in the system’s page cache,
but is not written to disk before the write returns to the caller. This improves
performance, but carries the risk of data loss if the system crashes before the data
is flushed to disk.
atomic operation An operation that either succeeds completely or fails and leaves everything as it
was before the operation was started. If the operation succeeds, all aspects of the
operation take effect at once and the intermediate states of change are invisible.
If any aspect of the operation fails, then the operation aborts without leaving
partial changes.
BLI (block-level
incremental) backup
A Veritas backup capability that does not store and retrieve entire files. Instead,
only the data blocks that have changed since the previous backup are backed up.
boot disk A disk that is used for the purpose of booting a system.
boot disk group A private disk group that contains the disks from which the system may be booted.
buffered I/O A mode of I/O operation (where I/O is any operation, program, or device that
transfers data to or from a computer) that first transfers data into the Operating
System buffer cache.
bootdg A reserved disk group name that is an alias for the name of the boot disk group.
cluster mounted file
system
A shared file system that enables multiple hosts to mount and perform file
operations on the same file. A cluster mount requires a shared storage device that
can be accessed by other cluster mounts of the same file system. Writes to the
Glossary