Working with DASDs

You might have to prepare DASD for use, configure troubleshooting functions, or configure special device features for your DASDs.

Most of the following tasks involve writing to and reading from device attributes in sysfs. This method is useful on a running system where you want to make dynamic changes. For changes that persist across IPLs, use the configuration file /etc/zipl.conf for DASDs that are part of the root file system and /etc/dasd.conf for data disks. An example of how to define a DASD device persistently is in Red Hat Enterprise Linux 7.5 Installation Guide. For a general discussion of configuration files, see Red Hat Enterprise Linux 7.5 System Administrator's Guide.

See Working with newly available devices to avoid errors when you are working with devices that have become available to a running Linux instance.