In some high-availability setups, root and boot disks of a Linux
installation are copied to remote sites that can take over execution
of a Linux workload in case of an outage of the original site.
A site in this context is an execution environment such as an LPAR
or z/VM guest.
Each site may provide a different set of devices, or require different
parameters to be applied per device. chzdev supports site-specific
device configuration for up to 10 sites. Each site is identified by
a number in the range 0 to 9. You can provide a separate set of persistent
device configuration for each site. The IPL Load parameter value specified
during boot determines the currently active site. Only the device
configuration of the active site is applied during boot and when new
devices become available. A common configuration can be provided that is
applied when no site-specific configuration is available for a device in
the active site.
User can use the --site parameter to configure devices for a specific
site only. Configuration actions without a site parameter apply to the
common configuration.
During the boot, the active site configuration is chosed based on the
IPL LOADPARM variable. If the LOADPARM contains no valid site-id (0 to 9),
the fallback-site id will be used. The fallback-site-id can also be
configured with the zdev tools by not specifying the --site parameter.
Some of the new chzdev/lszdev commands with site-parameter can be as
follows
1. chzdev -ep f001 --site 3
This command is used to configure the device f001 for the site 3. During
boot, if the LOADPARM value is S3, this device configuration will be
used.
2. lszdev --site 3
This command lists all the devices which are configured for site 3.
3. chzdev -ep f001
Above command does not have a --site parameter. This device settings
will be used for the following conditions
1. When the loadparm specifies a site, (e.g S3), and the device does not
have an associated config-set, zdev uses fallback config set.
2. When the loadparm does not specify any site information, then the
fallback config set will be used.
When the loadparm specifies a site, and the device does not have an
associated config set, nor a fallback site, nothing is configured for this
device.
Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Vineeth Vijayan <vneethv@linux.ibm.com>
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
This commit is based on the s390-tools-1.39.0 version.
Changes on top of s390-tools-1.39.0:
- Add MIT license to all source files
- Add LICENSE file
- Transform REAMDE to README.md (markdown)
- Add AUTHORS.md file
- Add CONTRIBUTING.md file
- Move changelog from README to CHANGELOG.md file
Reviewed-by: Stefan Haberland <sth@linux.vnet.ibm.com>
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
