Content of dracut.conf
# additional kernel modules to the default
add_drivers+="cciss"

omit_drivers+="hpsa"
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[root@localhost boot]# lsinitrd initramfs-4.4.176-1.el7.elrepo.x86_64-cciss.img | grep cciss
Image: initramfs-4.4.176-1.el7.elrepo.x86_64-cciss.img: 31M
-rwxr--r--   1 root     root       179088 Mar  4 04:42 usr/lib/modules/4.4.176-1.el7.elrepo.x86_64/kernel/drivers/block/cciss.ko
[root@localhost boot]# lsinitrd initramfs-4.4.176-1.el7.elrepo.x86_64-cciss.img | grep hpsa

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