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7.41. dracut

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, the dracut utility incorrectly printed an error message if the /tmp/net.$netif.override file did not exist. With this update, dracut verifies whether /tmp/net.$netif.override exists before it attempts to read it, which prevents the described error from occurring.
Prior to this update, the dracut logrotate configuration determined that the "time" option had priority over the "size" option. Consequently, the dracut logs were rotated only yearly regardless of their size. This update removes the "time" option of the logrotate configuration, and the dracut logs now rotate when the size exceeds 1 MB.
If "ip=ibft" was specified as a kernel command-line argument, but the "ifname=<iface>:<mac>" parameter was not, dracut did not handle network interfaces correctly. As a consequence, iSCSI disks were not connected to the system, and thus the system failed to boot. With this update, dracut handles "ip=ibft" as a kernel command-line argument, even without "ifname=<iface>:<mac>", and iSCSI disks are now connected to the system successfully resulting in successful system boot.
If the /etc/crypttab file did not contain a new line as the last character, dracut failed to parse the last line of the file, and the encrypted disk could not be unlocked. This update fixes dracut to handle /etc/crypttab without a new line at the end, and the encrypted disk specified on the last line is now handled as expected, requesting a password and unlocking the disk.
If the /etc/lvm/lvm.conf file had host tags defined, the initramfs virtual file system did not insert the /etc/lvm/lvm_hostname.conf file during kernel upgrade, which previously led to a boot failure. This update adds /etc/lvm/lvm_hostname.conf along with /etc/lvm/lvm.conf, and the system now boots with host tags as intended.
Previously, dracut did not parse the kernel command line correctly for some iSCSI parameters, which led to iSCSI disks not being connected. With this update, dracut parses the kernel command-line parameters for iSCSI correctly, and iSCSI disks are now connected successfully.
Due to an internal change in the nss-softokn-freebl package, dracut could not build an initramfs file in FIPS mode. To fix this bug, nss-softokn-freebl delivers its own dracut module and dracut now requires nss-softokn-freebl as a dependency. As a result, dracut can build FIPS-enabled initramfs with all files.
When network parameters were specified on the kernel command line, dracut only attempted to connect to iSCSI targets provided the network could be brought up. Consequently, for misconfigured networks, iSCSI firmware settings or iSCSI offload connections were not explored. To fix this bug, dracut now attempts to connect to the iSCSI targets even if after a certain timeout no network connection can be brought up. As a result, iSCSI targets can be connected even for misconfigured kernel command-line network parameters.
Due to changes in FIPS requirements, a new deterministic random-byte generator (drbg) was added to the kernel for FIPS purposes. With this update, dracut loads drbg as other kernel modules in FIPS mode.


With this update, dracut can boot from iSCSI on a network with VLANs configured, where the VLAN settings are stored in the iBFT BIOS.
LVM thin volumes are now supported in initramfs.
Users of dracut are advised to upgrade to these updated packages, which fix these bugs and add these enhancements.