7.43. dracut

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Updated dracut packages that fix several bugs and add two enhancements are now available for Red Hat Enterprise Linux 6.
The dracut packages include an event-driven initramfs generator infrastructure based on the udev device manager. The virtual file system, initramfs, is loaded together with the kernel at boot time and initializes the system, so it can read and boot from the root partition.

Bug Fixes

Previously, dracut could not handle uppercase MAC addresses for the PXE "BOOTIF=" parameter. As a consequence, a machine with a dracut generated initramfs could not boot over the network, when the "BOOTIF=" parameter contained uppercase MAC addresses. With this update, dracut converts internally the MAC addresses to lowercase. Now, a machine with a dracut generated initramfs can boot over the network successfully when the "BOOTIF=" parameter contains uppercase MAC addresses.
Previously, the default mount option of the /proc/ directory during boot up was "mount -t proc -o nosuid,noexec,nodev proc/proc". This resulted in inaccessible device nodes in the /proc/ directory for some kernel drivers. The default mount option of the /proc directory has been changed to "mount -t proc proc /proc" and all kernel modules now load successfully.
Previously, dracut could not use the Internet Small Computer System Interface (iSCSI) and dmsquash-live module together. As a consequence, it was not possible to boot from a live medium over iSCSI. After this update, a dracut-generated initramfs, which contains the iSCSI and dmsquash-live modules, is able to boot a live medium via iSCSI. This can be done using the kernel command "root=live:LABEL=<partition-or-iso-label> netroot=iscsi: ".
Previously, the new Brocade switch firmware took longer to complete the BCBx negotiation and a dracut-generated initramfs did not wait long enough for the DCBx negotiation. Now, the initramfs sleeps for three seconds after loading the "802q" kernel module and the DCBx negotiation with the new Brocade switch firmware completes successfully.
When using the "live_ram" parameter for booting from live media, the dracut-generated initramfs ejected the medium. After this action, a reboot caused the machine to not boot from the medium again, even if it was intended. After this update, dracut honors the "no_eject" kernel command-line parameter. Now, if "no_eject" is given on the kernel command-line, the dracut-generated initramfs no longer ejects the live medium after copying it to the RAM.
In FIPS mode, the kernel image has to be validated by a checksum. The sha512hmac tool reads the absolute path of the file to check from the checksum file. Previously, if "/boot" was not on a separate file system, dracut mounted the root file system to "/sysroot". The "/sysroot/boot" partition was not accessible with the "/boot" path and the sha512hmac tool could not access the file in "/boot" to check for. The check failed and the boot process was cancelled. Consequently, the boot processes did not succeed in FIPS mode if "/boot" was not on a separate file system. Now, dracut creates a symbolic link from the "/sysroot/boot" partition to the "/boot" partition in the initramfs and the sha512hmac tool can check the kernel image and the machine can continue booting, if the check was successful.
Previously, the kernel module "scsi_dh_alua" was not included in the initramfs and as a consequence, "scsi_dh_alua" could not be preloaded via the "rdloaddriver" kernel command. The "scsi_dh_alua" kernel module is now included in the initramfs and "scsi_dh_alua" can be preloaded successfully using "rdloaddriver".
Previously, dracut did not strip the kernel modules as mentioned in the man page. Consequently, initramfs size grew very big if the customer had kernel modules with a lot of debug info. The dracut utility now strips the kernel modules, except when in FIPS mode, and as a result, the initramfs size is smaller and can be loaded on machines with small memory.


Documentation for the "rd_retry=" boot option has been added to the dracut(8) man page.
The dracut utility can now boot from iSCSI on a network with virtual LANs configured, where the virtual LAN settings are stored in the iSCSI Boot Firmware Table BIOS.
Users of dracut are advised to upgrade to these updated packages, which fix these bugs and add these enhancements.
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