HP 12000 HP VLS Solutions Guide Design Guidelines for Virtual Library Systems - Page 150

configuration details and examples. HP recommend setting stinit to load via an init file (for example, /etc/rc.local on Redhat) to ensure it is loaded properly. ◦ NetWorker supports Linux udef device naming. See the EMC whitepaper Persistent Binding and udef Changes for EMC NetWorker for details (document h5795, available at https:// powerlink.emc.com). • UNIX device configuration: The following guidelines apply to Networker on UNIX: ◦ AIX - Ensure that variable block mode is enabled. AIX does not have a persistent naming option, although the ODM database generally tracks device links properly across reboots. ◦ Solaris - Ensure that the tape drive is supported in the kernel. This is most easily done by running strings /kernel/drv/sparcv9/st |grep -i LTO (for LTO) and comparing this to the tape drive string found in /var/adm/ messages. If tape drive is unsupported by the kernel, configure st.conf to allow variable block mode. For Solaris Persistent Naming, see Section 8, Persistent Binding for Tape Devices available at http:// docs.sun.com/source/819-0139/. ◦ HPUX - An issue exists when EMC NetWorker uses tape library SCSI commands via activation of a Common Device Interface (CDI) with the HPUX 11.31. Operating CDI is activated by default in EMC NetWorker. When CDI is activated, HPUX estape driver has a problem distinguishing between EOT and BOT, thus causing job failures. The EMC messages log may contain the following as symptom: Oct 22 13:30:29 nairobi: NetWorker media: (warning) rd=suzanne.ebs.net:/dev/rmt/c8t2d0BESTnb writing: continuation, No space left on device, at file 2 record 0Oct 22 13:30:29 nairobi: NetWorker media: (emergency) continuation, No space left on device, at file 2 record 0 Media is marked as full and the application selects another tape and progresses through the same until all tapes are listed as "full." The recommended action is to obtain and install HPUX 11.31 patch PHKL_36312. Networker Deduplication Guidelines In addition to the NetWorker general guidelines, the following guidelines apply to a VLS with deduplication enabled: • Tape Retention Planning: Create media pools based on retention period. Mixing retention periods will prevent cartridge expiration reclamation and leads to poor storage utilization. Space used for the shorter retention backup is not reclaimed until all backups on the tape are expired. That is, the backup application cannot reuse/reformat the tape until all backups have exceeded their protection period. The backup application will not reuse expired cartridges until all spare formatted virtual cartridges are used, so in this case HP recommends either removing unneeded virtual cartridges or creating a script on the cell server to automatically reformat expired cartridges on a regular basis. • Enable auto-ejection: Enable auto-ejection by setting the idle device timeout parameter in the NetWorker autochanger (tapes will not be deduplicated until they are ejected from the virtual tape drive). • Oracle RMAN Scripting: See Oracle RMAN Scripting for details. • Lotus Notes: for deduplication to work you must set parallelism to 1 for Lotus Notes backups. • Disable multiple streams per data file for SQL database backups: Multiple streams from a given data file will reduce deduplication effectiveness. For some database backups, NetWorker can create multiple savestreams per database file. Disabling this feature is critical when using deduplication. Multiple savesets from a database is not an issue, only multiple streams from a data file. Disable the "Striped Backup" feature in the NetWorker Module for Microsoft SQL Server because this creates multiple streams from each data file. To disable this for a scheduled 150 VLS Configuration and Backup Application Guidelines