The next several entries in the Implementers blog are going to concentrate on using tape devices in Linux partitions implemented in an IBM i environment. In this first entry, I'll show how physical tape devices can be used in PowerLinux.
I've recently had several IBM i customers request assistance with setting up PowerLinux to use physical tape devices. Since this seems to be becoming a prevalent configuration, I thought I would take this blog entry to share some information on the process for establishing connectivity to physical tape devices.
Three packages are required for Linux support of IBM tape drivers and libraries:
- lin_tape—Device driver for managing IBM libraries and IBM drives
- lin_taped—Daemon program used to automatically create or delete special files under the /dev directory that correspond to the attached or detached tape devices.
- itdt—Tape utility to access various functions of the Linux device driver
These packages can be downloaded from FixCentral:
The above selection from Fix Central will provide access to the lin_tape and lin_taped packages. For the itdt package, select tape diagnostic tool ITDT for the tape drivers and software selection. Also, make sure to select the correct platform (in this case, Linux 64-bit.pSeries for Linux running on the POWER platform). The packages presented after selecting <Continue> will be segmented based on Linux distribution and version—make sure to select the packages from the distribution and version that you have installed.
Installation of the lin_tape package is a little different from normal package installations in that it's distributed as a source rpm that needs to be built into a binary rpm. The ability to build the rpm has a number of dependencies that vary based on the distribution. As an example, for SuSE SLES 11 the following additional packages need to be installed from the distribution media:
The following command will actually build the lin_tape binary rpm:
The result of the above command will be a binary rpm that will be located in the /usr/src/packages/RPMS/ppc64 directory. Installation of the resulting rpm can be accomplished with the following command:
Installation of the tape daemon package can be accomplished with the following command:
The tape driver itself is a kernel module that will be loaded when the kernel detects the tape drive connection. Prior to loading the module, it's necessary to modify the configuration of the modprobe command (that's the command that causes kernel modules to be loaded) to allow unsupported modules. The following entry needs to be added to the modeprobe configuration file (/etc/modproe.do/unsupported-modules):
The tape driver will be loaded automatically the next time Linux is booted. To load the module without rebooting Linux, run the following command:
As a result of the above command two new tape devices will be created:
These devices can now be used as the target for standard Linux tape commands, such as the tar and cpio commands.