Path: utzoo!attcan!uunet!legato!mojo From: mojo@legato (Joseph Moran) Newsgroups: comp.unix.wizards Subject: Re: Trashed Disk Labels Under Sun OS 3.5 Message-ID: <919@legato.LEGATO.COM> Date: 11 Aug 89 04:58:23 GMT References: <5253@wiley.UUCP> <18969@mimsy.UUCP> Reply-To: mojo@legato (Joseph Moran) Organization: Legato Systems, Inc., Palo Alto, CA Lines: 20 In article <18969@mimsy.UUCP> chris@mimsy.UUCP (Chris Torek) writes: >SunOS starts swap space at sector 0 of the swapon partition. The label >is in disk sector 0. Thus, SunOS will swap on top of the label if the >partition begins at disk sector 0. SunOS 3.x and earlier followed the conventions of 4.2 BSD for allocating swap space which resulted in disk labels and boot blocks getting trashed if you swapped onto a partition that started at cylinder 0 (typically `a' and `c'). SunOS 4.0 and greater has a totally different VM system. During this rewrite, code was added to skip over the first part of each swap device to prevent the "disk label overwrite" problem. Joseph Moran Legato Systems, Inc. 260 Sheridan Avenue Palo Alto, CA 94306 (415) 329-7886 mojo@Legato.COM or {sun,uunet}!legato!mojo