initrd.img(Decompress /DIY)

=============
Decompress initrd:

#cp /boot/initrd-2.6.16.21-0.8-default ~/initrd-2.6.21.gz
#mkdir AAA
#mv initrd-2.6.21.gz AAA/
#gunzip initrd-2.6.21.gz
#cpio –idcmv < initrd-2.6.21.gz
#ls
bootsplash  etc   initrd-2.6.21      lib   root  sys
bin  dev         init    proc  sbin  tmp

=============
Create DIY-initrd:

#mkdir Hello_test/
#touch Hello_test/hello.ko
#find . | cpio -c -o > initrd-2.6.21.DIY.img
#mkdir ../CCC;cp initrd-2.6.21.DIY.img ../CCC
#cpio –idcmv < initrd-2.6.21.DIY.img

linuxzenworks:~/CCC # ls
Hello_test  dev   init-2.6.21.DIY.img    initrd-2.6.21.img  root  tmp
bin         etc   initrd-2.6.21          lib                sbin
bootsplash  init  initrd-2.6.21.DIY.img  proc               sys

=============
"init"(2.6) is alternative for linuxrc(2.4)

linuxzenworks:~/BBB # cat init|grep modprobe
modprobe ide-core $params
modprobe ide-disk $params
modprobe scsi_mod $params
modprobe sd_mod $params
modprobe piix $params
modprobe scsi_transport_spi $params
modprobe mptbase $params
modprobe mptscsih $params
modprobe mptspi $params
modprobe ide-generic $params
modprobe processor $params
modprobe thermal $params
modprobe fan $params
modprobe edd $params
modprobe reiserfs