Tivoli is going to deliver Check Sum support in a future release. But, you have no way to read the tape back to verify the tape is good based on my understanding of the solution provided. The checksum is verified during the restore process or a copy from one storage pool to another. So, if you create a primary tape and then perform a backup command against the storage pool it is in to create another copy I suspect the checksum will be checked.
If you use a high end drive there is parity and checksum already built in. -----Original Message----- From: William SO Ng [mailto:[EMAIL PROTECTED]] Sent: Thursday, March 07, 2002 9:15 PM To: [EMAIL PROTECTED] Subject: Re: Tape backup verification I'm new to TSM, so please be patient with me. Let say I backup directly from clients to tape, so my primary pool is tape and I do not use a disk pool. Since I cannot find "verify" command in TSM, so I wonder how TSM do the verification ? Is the data already been verified when it writes to tape ? If yes, by whom e.g. tape driver, OS, TSM ? If it is by tape driver or OS, this mean that it is OS or tape driver dependent. So some of the OS or tape driver MAY NOT verify the writing process, so there is no guarentee the data that backup is good ? If the verification is done by TSM, then how does TSM do the verfication, is it by checksum or read after write ? Thanks, Regards William Tivoli Software, IBM Software Group, IBM China/Hong Kong Limited 11/F, PCCW Tower, Taikoo Place, 979 King's Road, Hong Kong Internet : [EMAIL PROTECTED] Tel: 2825-7613 Fax: 2825-0022 Bill Mansfield <WMansfield@SOLUTIONTECHN To: [EMAIL PROTECTED] OLOGY.COM> cc: Sent by: "ADSM: Dist Stor Subject: Re: Tape backup verification Manager" <[EMAIL PROTECTED]> 03/08/02 07:29 AM Please respond to "ADSM: Dist Stor Manager" When you backup the primary storage pool to the copy storage pool, it will read the primary pool tape. In the event the primary tape is bad, you'll get a bunch of errors in the activity log. _____________________________ William Mansfield Senior Consultant Solution Technology, Inc William SO Ng <[EMAIL PROTECTED]> Sent by: "ADSM: Dist Stor Manager" <[EMAIL PROTECTED]> 03/07/2002 03:14 AM Please respond to "ADSM: Dist Stor Manager" To: [EMAIL PROTECTED] cc: Subject: Tape backup verification Hello everyone, I have some questions about backup verification and would like to seek some advice. When I backup using TSM, how can I verify that the backup is good ? What I mean is when TSM write to tape, how do I verify that the write-to-tape process is good. I come from VMS backup. In VMS, it has a command: BACKUP /VERIFY, which will write the file to tape, rewind the tape and read the backup file. This will ensure that the file I wrote to the tape is good. The disadvantage is backup time is much longer. How does TSM do backup verification ? By checksum, by rewind and read ? Is it possible to specifiy the verification method ? Regards William Tivoli Software, IBM Software Group, IBM China/Hong Kong Limited 11/F, PCCW Tower, Taikoo Place, 979 King's Road, Hong Kong Internet : [EMAIL PROTECTED] Tel: 2825-7613 Fax: 2825-0022
