Storix Software SBAdmin Linux System Recovery Guide - Manual (Page 10)

Storix System Backup Administrator 10 Version 8.2 Linux System Recovery Guide
The product will work quite well on systems with Devfs implemented as long as the system maintains the
classic device naming conventions as well. This is the default for most Linux implementations using Devfs.
All functions of the product will work the same on a Devfs system as for those not using Devfs, but all
references to disks, partitions and tape devices will use the classic names. SBAdmin also attempts to
cross-references the devfs names to the classic names whenever the system configuration files use the
devfs names (as occurs automatically when some Linux distros are installed). System configuration files
which may use either devfs or classic names include:
•
/etc/fstab – Filesystem definitions
•
/etc/raidtab – Software RAID device definitions
•
/etc/mtab – Mounted filesystem table (automatically updated by the system)
To avoid any potential problems if you are using Devfs, you should make sure these files reference the
classic disk and partition names, such as /dev/sda (first SCSI disk) and /dev/hdc3 (third partition on the
third IDE disk) whenever possible. If you attempt to perform a
System Backup with SBAdmin and are
informed that the root filesystem, or any other filesystem, is either not found or not mounted, then SBAdmin
may have been unable to determine the devfs names, and you probably need to put the classic names in
the /etc/fstab file.
Boot Loaders
SBAdmin will attempt to determine which boot loader the system is currently using when performing a
system backup. If the backup process is unable to determine the boot loader used, the backup will fail.
Initial Ramdisk (initrd/initramfs) Support
One of the most difficult issues with any system recovery product is trying to figure out how to make the
system bootable. The configuration files restored from the backup may no longer be applicable if changes
to the hardware or storage configuration have been made. After a SBAdmin System Installation is
completed, the boot loader is configured to make the system bootable based on that kernel and the root
filesystem. This is often not enough information to make everything available at system startup that is
required. For example, if your root filesystem resides on a SCSI disk, and the SCSI adapter support is not
built into your kernel, then your system probably loads an Initial Ram Disk (initrd/initramfs) containing the
SCSI adapter support, which allows the adapter to be configured before attempting to mount the root
filesystem. SBAdmin will determine if an initrd is necessary and create one automatically. If not required,
SBAdmin will configure the system to boot from your kernel without an initrd image. If your kernel has built-
in support for any devices or filesystems required to mount your root filesystem, you should have no
problems. If an initrd image is required, you are given the opportunity at the end of the system recovery
process to configure your own boot loader, or modify the boot loader configuration file to handle any
potential problems. Note that SBAdmin does not support systems using monolithic kernels (no loadable
kernel modules).
More specific information creating an Initial Ramdisk Image is provided later in this document.