At CMU we have used Sun OS 3.5 as a starting point to boot Mach, so our installation notes are based on that. We have received the following advice on dealing with Sun OS 4 from other sites. Date: Mon, 14 May 90 17:44:31 MDT From: "Glenn P. Davis" To: info-mach@CS.CMU.EDU Subject: Sharing disks with Sun OS 4.1 Hi. I have the following configuration : Sun 3/60 monochrome disk 0 - 1355 disk 2 - CDC Wren IV Mach is loaded on the 1355 and SunOS is loaded on sd2. Both share some "user" files (home directories, local source). The purpose of this note is to warn others of some gotcha's I hit in upgrading to SunOS 4.1. --- The first thing is that the new sun 'boot' code won't boot mach, so don't do /usr/mdec/installboot from SunOS 4.1 targeting your mach disk. What happens is as follows: Boot: sd()vmunix # Mach on sd0 Size x+y+z bytes Invalid Page Bus Error: Vaddr: 0E09D4D4, Paddr: 000014D4, Type: 0, Write, FC 5, Size 4 at 0x0E00407C Go figure. Note, the 4.0.3 and 3.5 SunOS boot code work. I tar'ed SunOS 3.5 /usr/mdec/ onto my mach disk, did a chroot to the mach root and did 3.5 installboot to recover. --- The second thing is that file systems created by SunOS 4.1 'newfs' can be created with more than 2048 inodes per cylinder group, which would preclude their use under Mach 2.5 or earlier releases of Sun OS. Sun OS 4.1 can use filesystems created in the older format. So, if you want a partition to be usable under both, be sure to use the older format. This is detailed in the Sun OS 4.1 Release Manual, page 7. Good luck Glenn P. Davis UCAR / Unidata PO Box 3000 1685 38th St. Boulder, CO 80307-3000 Boulder, CO 80301 (303) 497 8643 The following is a change to the sample session for installing Mach that is included in the Mach 2.5 Sun 3 Installation Notes on page 6. Sample session for installing Mach on Sun 4 on the network with a formatted Priam 638 disk, a 1/4" Mach tape distribution, and a SunOS 4.X boot tape. Session output Comments Start with a halted machine >b st() Boot from the 1/4" tape Boot: st(0,0,0) Boot:st(0,0,2) Load the copy program Standalone Copy From:st(0,0,3) Copy mini-unix To:sd(0,0,1) into the b partition Boot:sd(0,0,1)vmunix -asw Boot mini-unix [... about 20 lines of mini-unix messages ...] root filesystem type (4.2 nfs): 4.2 root device (disk%d[a-h]): sd0b swap filesystem type (spec 4.2 nfs): spec swap device (disk%d[a-h]): sd0b Swapping on root device? y [... more mini-unix messages ...]