On Sat, 3 May 2003, Werner Puschitz wrote: > > On Sat, 3 May 2003, Robert P. J. Day wrote: > > > so why is initrd.img necessary for LVs even when it has > > no modules? > > The initrd image is needed to run a few initial commands within the initrd > image (filesystem). The system loads the "linuxrc" file from the initrd > image. This file is a script which scans the disks for volume groups, > etc. and mounts the root filesystem. For example, on my system linuxrc > runs at the end the following command: > mount -o defaults --ro -t ext3 /dev/Volume00/LogVol01 /sysroot > > You can find the script "linuxrc" in the root directory of the initrd > image. You will also see that the linuxrc script uses the script > interpreter nash(8). This is a very small interpreter which has some > important built in commands like mount, umount, etc. See man nash(8). > You can find the nash interpreter in the bin directory of the initrd > image. > > So basically, you need the initrd image for finding and mounting the root > fileystem. Here is a printout of my linuxrc script: > > #!/bin/nash > echo "Loading lvm-mod module" > insmod /lib/lvm-mod.o > echo "Loading jbd module" > insmod /lib/jbd.o > echo "Loading ext3 module" > insmod /lib/ext3.o ... snip ... all of this makes sense. and since i still haven't had the chance to reinstall with LVM, i just want to verify what should be a fairly obvious observation -- the initial initrd.img that one finds upon booting for the first time must have been created as a result of the installation choices, right? from the excerpt werner provided above, it seems clear that that particular linuxrc corresponds to what the RH install would generate by default: ext3 and LVM supported as modules. rday
