Alternative tracks are actually provided for in the controller and were last used in the 3990-6. The advent of 2105 controller and emulation of it by disk arrays had no microcode to take advantage of/or use alternate tracks.
When you reformat the VTOC, this process in no way compromises any data on the volume. However, I understand that if this has not been done before now that it might appear to be a nuisance issue. Tom Moulder -----Original Message----- From: IBM Mainframe Discussion List [mailto:[EMAIL PROTECTED] On Behalf Of Michael Bradley Sent: Tuesday, July 31, 2007 11:16 AM To: [email protected] Subject: Re: EMC DMX3-1500 and REFORMAT VTOC Tom, ====================== What I have been told is that z/OS no longer uses the alternate tracks, so the reformat removes them from the VTOC. Frankly, I haven't looked into this deep enough to know how you would ever get a "bad" track since there is so little use of real 3390 disk volumes anymore to cause z/OS to try and use an alternate track in the VTOC. ====================== I can't argue the point. However, EMC requires "traditional" formatting, My recollection is that it has to do with certain IBM DASD models that DIDN'T have alternate tracks. Michael No virus found in this outgoing message. Checked by AVG Free Edition. Version: 7.5.476 / Virus Database: 269.11.0/927 - Release Date: 7/30/2007 5:02 PM ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
