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@mailman.eng.auburn.edu http://mailman.eng.auburn.edu/mailman/listinfo/veritas-bu