Hello fellow LUGODians, I wanted to share my experience with EXT3. I was able to upgrade my existing RH7.1 install to ext3 across the board and it was decidedly painless. I believe EXT3 is not built into the default RH 7.1 kernel, so I rebuilt the kernel (using the kernel-source 2.4.9-12 package) not only to support ext3 but to enable the DEVFS as well. As per Pete's presentation, DEVFS was easy to install. Migrating to ext3 was easy as well (a la tune2fs).
I had downloaded the Redhat 7.2 ISO images a couple of weeks ago, burned the two CDRs and began upgrading a different RH7.1 system RH7.2. It was there I ran into problems. RH7.2 comes with ext3 precompiled into the kernel (of course, in order to get kernel 2.4.9-13, I had to get the update RPM package). Once again, "tuning" my ext2 partitions to ext3 was easy. All I had to do was change my fstab entries and reboot. Voila--instant ext3. Now I wanted to convert the system to DEVFS. I had to get the latest RH7.2 kernel sources (2.4.9-13) and rebuild the kernel, making sure to include the ext3 and DEVFS modules, since RH7.2 does not come with DEVFS support built in. I also checked the "mount /dev filesystem at boot". Then I compiled then kernel and modules, installed everything, crossed my fingers, and rebooted. I got the message "kernel panic--no init image found." I had noticed as well that during the boot process, I was getting a wierd error "mknod failed: 17". I discovered that, since I use LILO, the new installation had a "initrd=" line. I tried to reboot, typing in "linux root=/dev/hda5 initrd= single" but to no avail--the same panic message ensued. Arg. Rebooting with the old stock kernel, I remarked off the "initrd=" image line in the lilo.conf file, re-ran lilo, then rebooted. Lo and behold, my new kernel finally booted correctly. After looking at the mkinitrd script, dmesg output, and the linuxrc script in the initrc image, I finally determined what the cause was: when using DEVFS, and with the "mount /dev filesystem at boot" option checked in the kernel build, the /dev filesystem is mounted right before the initrd image is loaded and linuxrc is run. linuxrc attempts to "mknod" the entries in a temporary filesystem and attempts to remount it (with the /dev filesystem mounted, this is where the wierd "mknod" error came from). This requires an entry for /dev/root, which doesn't exist. Since devfsd is not running, it cannot be created on demand. Further, the pivot_root command really messes things up--it seems to make the initial /dev mounting "go away". The solution was to prohibit /dev mounting on boot (I added an 'append="devfs=nomount"' line to /etc/lilo.conf). Then, the initrd image could run correctly. I then added at the top of /etc/rc.sysinit the following lines: # Find this at # http://www.atnf.csiro.au/~rgooch/linux/docs/devfs.html#persistence # echo -en "Mounting dev filesystem: " /bin/mount --bind /dev /dev-state /bin/mount -n -t devfs none /dev echo /sbin/devfsd /dev The "mount --bind..." keeps a persistent state of the /dev filesystem--this allows one to change permissions and ownership of items in the /dev filesystem and have them preserved across reboots. The "mount -n -t..." command actually mounts the /dev filesystem. The "devfsd..." line starts the DEVFS daemon. Doug (aka Dooglio) BTW: It would be nice to rework the linuxrc file in a DEVFS-only initrd image so it could take advantage of the devfs filesystem. The trouble is that pesky remounting and pivot_root stuff. I must admit that I'm in the dark as to the need for a boot image at all--what are the advantages? Why do we need it? On my RH7.1 system I have the image disabled (this is why I never ran into the DEVFS problem before). In fact, I can run my RH7.2 system just fine with the "initrd=" line in /etc/lilo.conf remarked off. EXT3 and DEVFS seem to be happy in both instances. On Mon, 24 Dec 2001, Peter Jay Salzman wrote: > [major snipage] > > pete -- R. Douglas Barbieri [EMAIL PROTECTED] www.dooglio.net _______________________________________________ vox-tech mailing list [EMAIL PROTECTED] http://lists.lugod.org/mailman/listinfo/vox-tech
