IBM Tivoli Storage Manager for UNIX and Linux Backup-Archive ...

is optional. See also stub file and residentfile. For HSM clients on UNIX or Linuxsystems, contrast with premigrated file.migrate-on-close recall modeA mode that causes a migrated file to berecalled back to its originating file systemtemporarily. Contrast with normal recallmode and read-without-recall recall mode.migration jobA specification of files to migrate, andactions to perform on the original filesafter migration. See also job file.migration thresholdHigh and low capacities for storage poolsor file systems, expressed as percentages,at which migration is set to start andstop.mirroringThe process of writing the same data tomultiple locations at the same time.Mirroring data protects against data losswithin the recovery log.mode A copy group attribute that specifieswhether to back up a file that has notbeen modified since the last time the filewas backed up. See modified mode andabsolute mode.modified modeIn storage management, a backupcopy-group mode that specifies that a fileis considered for incremental backup onlyif it has changed since the last backup. Afile is considered a changed file if thedate, size, owner, or permissions of thefile have changed. See also absolute mode.mount limitThe maximum number of volumes thatcan be simultaneously accessed from thesame device class. The mount limitdetermines the maximum number ofmount points. See also mount point.mount pointOn the Tivoli Storage Manager server, alogical drive through which volumes in asequential access device class areaccessed. For removable-media devicetypes, such as tape, a mount point is alogical drive that is associated with aphysical drive. For the file device type, amount point is a logical drive that isassociated with an I/O stream. Thenumber of mount points for a device classis defined by the value of the mount limitattribute for that device class. See alsomount limit.mount retention periodThe maximum number of minutes thatthe server retains a mountedsequential-access media volume that isnot being used before it dismounts thesequential-access media volume.mount wait periodThe maximum number of minutes thatthe server waits for a sequential-accessvolume mount request to be satisfiedbefore canceling the request.MTU See maximum transmission unit.NNagle algorithmAn algorithm that reduces congestion ofTCP/IP networks by combining smallerpackets and sending them together.named pipeA type of interprocess communicationthat permits message data streams to passbetween peer processes, such as betweena client and a server.NAS See network-attached storage.NAS nodeA client node that is a network-attachedstorage (NAS) file server. Data for theNAS node is transferred by a NAS fileserver that is controlled by the networkdata management protocol (NDMP). ANAS node is also called a NAS file servernode.native file systemA file system that is locally added to thefile server and is not added for spacemanagement. The hierarchical storagemanager (HSM) client does not providespace management services to the filesystem.native formatA format of data that is written to astorage pool directly by the Tivoli StorageManager server. Contrast with non-nativedata format.NDMPSee Network Data Management Protocol.NetBIOSSee Network Basic Input/Output System.550 IBM Tivoli Storage Manager for UNIX and Linux Backup-Archive Clients Version 6.1: Installation and User’s Guide