Chapter 19. Sample Parameter Files

download PDF
The IBM System z architectures use a special parameter file to set up networking before the installation program (anaconda) can be started. This section describes the contents of the parameter file.
The parameter file has a limit of 32 total parameters. To accommodate limitations of the parameter files, a new configuration file on a CMS DASD should be used to configure the initial network setup and the DASD specification. The .parm file should contain the real kernel parameters, such as root=/dev/ram0 ro ip=off ramdisk_size=40000, and single parameters which are not assigned to variables, such as vnc. Two new parameters which point the installation program at the new configuration file need to be added to the .parm file. They are CMSDASD and CMSCONF .
Where cmsdasd_address represents the list of the device ID of the CMS DASD device which contains the configuration file. This is usually the CMS user's 'A' disk. This option is applicable only for users who have a CMS formatted disk (z/VM) available.
For example: CMSDASD=191
Where configuration_file represents the name of the configuration file. This value must be specified in lower case. It is specified in a Linux style file name format. The CMS file REDHAT CONF is specified as redhat.conf. This option is applicable only for users who have a CMS formatted disk (z/VM) available.
For example: CMSCONFFILE=redhat.conf
Where dasd-list represents the list of DASD devices to be used by Red Hat Enterprise Linux.
Although automatic probing for DASDs is done if this parameter is omitted, it is highly recommended to include the DASD= parameter, as the device numbers (and therefore the device names) can vary when a new DASD is added to the guest. This can result in an unusable system.
For example: DASD=0.0.0100,0.0201-0.0.0204
The following parameters are required to set up networking:
Provides required device bus IDs for the various network interfaces.
qeth: SUBCHANNELS="read_device_bus_id,write_device_bus_id,
lcs: SUBCHANNELS="read_device_bus_id,write_device_bus_id"
Due to the length of the qeth command line, it has been broken into two lines.


The CTC, and NETIUCV drivers have been deprecated and are no longer supported in Red Hat Enterprise Linux.
For example (a sample qeth SUBCHANNEL statement):
The following parameters are optional:
Where string is the hostname of the newly-installed Linux guest.
Where type must be one of the following: qeth or lcs.
Where IP is the IP address of the new Linux guest.
Where network is the address of your network.
Where netmask is the netmask.
Where broadcast is the broadcast address.
Where gw is the gateway-IP for your eth device.
Where mtu is the Maximum Transmission Unit (MTU) for this connection.
Where server1:server2:additional_server_terms:serverN is a list of DNS servers, separated by colons. For example:
Where domain1:domain2:additional_dns_terms:domainN is a list of the search domains, separated by colons. For example:
PORTNAME=osa_portname | lcs_portnumber
This variable supports OSA devices operating in qdio mode or in non-qdio mode.
When using qdio mode: osa_portname is the portname specified on the OSA device when operating in qeth mode. PORTNAME is only required for z/VM 4.3 or older without APARs VM63308 and PQ73878.
When using non-qdio mode: lcs_portnumber is used to pass the relative port number as integer in the range of 0 through 15.
When installing under z/VM, you can add either PORTNO=0 (to use port 0) or PORTNO=1 (to use port 1) to the CMS configuration file to avoid being prompted for the mode.
The PORTNO= setting also works on LPAR, but you must place it directly in the parmfile rather than the CMS configuration file.
Add either LAYER2=0 or LAYER2=1 to the CMS configuration file to make the mode persistent when installing on a System z guest.
Use LAYER2=0 when the OSA is in layer 3 mode, and LAYER2=1 when the OSA is in layer 2 mode.
When specifying LAYER2=1, you can also specify VSWITCH=1 when connecting to a VSWITCH, or VSWITCH=0 when connecting directly to the OSA.
When specifying LAYER2=1 and a VSWITCH is not in use, you can use this parameter to specify the MAC address in the CMS configuration file.
FCP_* (FCP_1, FCP_2, ...)
These variables can be used on systems with FCP devices to preconfigure the FCP setup (these can be changed during the installation).
Use the following samples as a guide to formatting proper parameter files.
Sample file with minimally required parameters:
root=/dev/ram0 DASD=200


The installation program prompts the user for any required parameters not specified in the parameter file.
Sample file configuring a QETH networking device:
Example of redhat.parm file:
root=/dev/ram0 ro ip=off ramdisk_size=40000
Example of redhat.conf file (pointed to by CMSCONFFILE in redhat.parm)
Red Hat logoGithubRedditYoutubeTwitter


Try, buy, & sell


About Red Hat Documentation

We help Red Hat users innovate and achieve their goals with our products and services with content they can trust.

Making open source more inclusive

Red Hat is committed to replacing problematic language in our code, documentation, and web properties. For more details, see the Red Hat Blog.

About Red Hat

We deliver hardened solutions that make it easier for enterprises to work across platforms and environments, from the core datacenter to the network edge.

© 2024 Red Hat, Inc.