This is correct, but does not work at all cases stefanos -----Original Message----- From: veritas-bu-boun...@mailman.eng.auburn.edu [mailto:veritas-bu-boun...@mailman.eng.auburn.edu] On Behalf Of oersted Sent: Wednesday, September 16, 2009 5:53 PM To: VERITAS-BU@MAILMAN.ENG.AUBURN.EDU Subject: [Veritas-bu] Fragment size for LTO4 on NBU 6.x
tape drive will use LOCATE BLOCK to first file to restore, then search from there. wdlb5359 wrote: > What are people using for the fragment size on LTO4 (or I guess LTO3) with > NBU 6.x? > > I ask because the default is 1TB, i.e. more or less don't fragment. > > The argument for a large fragment is that the backup doesn't have to stop > so often as it does briefly at the end of each fragment to update the > Master, and also the inter-fragment file markers waste space..though > that's hardly a consideration on such large tapes now. > > The argument for a small fragment was that the tape can position at full > speed to the file marker for the appropriate fragment for a restore, > rather than reading the tar file from the top at read speed, which for a > large tape could be a very long time. > > We used to (dating back to DLT7000) set a 2GB fragment, as back then this > was thought a good idea in case you wanted to dd the tape to disk and read > it without NetBackup. UNIX file systems did not take files > 2GB. Well I > can't say we ever tried it and it's a silly small size now. > > But what are people using - 100GB? 200GB? Does it really make a > difference... > > William D L Brown > > > ----------------------------------------------------------- > This e-mail was sent by GlaxoSmithKline Services Unlimited > (registered in England and Wales No. 1047315), which is a > member of the GlaxoSmithKline group of companies. The > registered address of GlaxoSmithKline Services Unlimited > is 980 Great West Road, Brentford, Middlesex TW8 9GS. > ----------------------------------------------------------- > > _______________________________________________ > Veritas-bu maillist - Veritas-bu < at > mailman.eng.auburn.edu > http://mailman.eng.auburn.edu/mailman/listinfo/veritas-bu +---------------------------------------------------------------------- |This was sent by sola...@cablespeed.com via Backup Central. |Forward SPAM to ab...@backupcentral.com. +---------------------------------------------------------------------- _______________________________________________ Veritas-bu maillist - Veritas-bu@mailman.eng.auburn.edu http://mailman.eng.auburn.edu/mailman/listinfo/veritas-bu _______________________________________________ Veritas-bu maillist - Veritas-bu@mailman.eng.auburn.edu http://mailman.eng.auburn.edu/mailman/listinfo/veritas-bu