Parameter and Configuration Files - Red Hat Enterprise Linux Manual

Chapter 26. Parameter and Configuration Files

26.1. Required parameters
26.2. The z/VM configuration file
26.3. Installation network parameters
26.4. VNC and X11 parameters
26.5. Loader parameters
26.6. Parameters for kickstart installations
26.7. Miscellaneous parameters
26.8. Sample parameter file and CMS configuration file

The IBM System z architecture can use a customized parameter file to pass boot parameters to the kernel and the installer. This section describes the contents of this parameter file.

You need only read this section if you intend to change the shipped parameter file. You need to change the parameter file if you want to:

automate the user input for linuxrc or the loader (refer to Chapter 21, Installation Phase 1: Configuring a Network Device and Chapter 22, Installation Phase 2: Configuring Language and Installation Source).
install unattended with kickstart.
choose non-default installation settings that are not accessible through the installer's interactive user interface, such as rescue mode.

The parameter file can be used to set up networking non-interactively before the installation program (loader and anaconda) starts.

The kernel parameter file is limited to 895 characters plus an end-of-line character. The parameter file can be variable or fixed record format. Fixed record format increases the file size by padding each line up to the record length. Should you encounter problems with the installer not recognizing all specified parameters in LPAR environments, you can try to put all parameters in one single line or start and end each line with a space character.

For more details on kernel parameters and different possibilities of specifying them, see the chapter on booting Linux and the chapter on kernel parameters in Linux on System z Device Drivers, Features, and Commands on Red Hat Enterprise Linux 6.

The parameter file contains kernel parameters, such as root=/dev/ram0 or ro, and parameters for the installation process, such as vncpassword=test or vnc.

26.1. Required parameters

The following parameters are required and must be included in the parameter file. They are also provided in the file generic.prm in directory images/ of the installation DVD:

root=file_system: where file_system represents the device on which the root file system can be found. For installation purposes, it must be set to /dev/ram0, which is the ramdisk containing the Red Hat Enterprise Linux installation program.
ro: mounts the root file system, which is a ramdisk, read-only.
ip=off: disables automatic network configuration.
ramdisk_size=size: modifies the memory size reserved for the ramdisk to ensure that the Red Hat Enterprise Linux installation program fits within it. For example: ramdisk_size=40000.

The file generic.prm also contains the additional parameter cio_ignore=all,!0.0.0009. This setting speeds up boot and device detection on systems with many devices. The installer transparently handles the activation of ignored devices.

Important - adapt the cio_ignore parameter to your system

To avoid installation problems arising from cio_ignore support not being implemented throughout the entire stack, adapt the cio_ignore= parameter value to your system or remove the parameter entirely from your parameter file used for booting (IPL) the installer.

When installing from an FCP-attached DVD drive, and you encounter a problem with ignored devices, select the menu option clear blacklist in linuxrc (refer to Chapter 21, Installation Phase 1: Configuring a Network Device) to remove the list of ignored devices.

26.2. The z/VM configuration file

This applies only if installing under z/VM. Under z/VM, you can use a configuration file on a CMS-formatted disk. The purpose of the CMS configuration file is to save space in the parameter file by moving the parameters that configure the initial network setup, the DASD, and the FCP specification out of the parameter file (refer to Section 26.3, "Installation network parameters").

Each line of the CMS configuration file contains a single variable and its associated value, in the following shell-style syntax: variable=value .

You must also add the CMSDASD and CMSCONFFILE parameters to the parameter file. These parameters point the installation program to the configuration file:

CMSDASD=cmsdasd_address: Where cmsdasd_address is the device number of a CMS-formatted disk that contains the configuration file. This is usually the CMS user's A disk.
For example: CMSDASD=191
CMSCONFFILE=configuration_file: Where configuration_file is the name of the configuration file. This value must be specified in lower case. It is specified in a Linux file name format: CMS_file_name.CMS_file_type.
The CMS file REDHAT CONF is specified as redhat.conf. The CMS file name and the file type can each be from one to eight characters that follow the CMS conventions.
For example: CMSCONFFILE=redhat.conf

26.3. Installation network parameters

The following parameters can be used to set up the preliminary network automatically and can be defined in either the parameter file or the CMS configuration file. The parameters in this section are the only parameters that can also be used in a CMS configuration file. All other parameters in other sections must be specified in the parameter file.

NETTYPE='type'

Where type must be one of the following: qeth, lcs, or ctc. The default is qeth.

Choose lcs for:

OSA-2 Ethernet/Token Ring
OSA-Express Fast Ethernet in non-QDIO mode
OSA-Express High Speed Token Ring in non-QDIO mode
Gigabit Ethernet in non-QDIO mode

Choose qeth for:

OSA-Express Fast Ethernet
Gigabit Ethernet (including 1000Base-T)
High Speed Token Ring
HiperSockets
ATM (running Ethernet LAN emulation)

SUBCHANNELS='device_bus_IDs'

Where bus_IDs is a comma-separated list of two or three device bus IDs.

Provides required device bus IDs for the various network interfaces:

qeth: SUBCHANNELS='read_device_bus_id,write_device_bus_id,data_device_bus_id'lcs or ctc: SUBCHANNELS='read_device_bus_id,write_device_bus_id'

For example (a sample qeth SUBCHANNEL statement):

SUBCHANNELS='0.0.f5f0,0.0.f5f1,0.0.f5f2'

PORTNAME='osa_portname' , PORTNAME='lcs_portnumber'

This variable supports OSA devices operating in qdio mode or in non-qdio mode.

When using qdio mode (NETTYPE='qeth'), osa_portname is the portname specified on the OSA device when operating in qeth mode.

When using non-qdio mode (NETTYPE='lcs'), lcs_portnumber is used to pass the relative port number as a decimal integer in the range of 0 through 15.

PORTNO='portnumber'

You can add either PORTNO='0' (to use port 0) or PORTNO='1' (to use port 1 of OSA features with two ports per CHPID) to the CMS configuration file to avoid being prompted for the mode.

LAYER2='value'

Where value can be 0 or 1.

Use LAYER2='0' to operate an OSA or HiperSockets device in layer 3 mode (NETTYPE='qeth'). Use LAYER2='1' for layer 2 mode. For virtual network devices under z/VM this setting must match the definition of the GuestLAN or VSWITCH to which the device is coupled.

To use network services that operate on layer 2 (the Data Link Layer or its MAC sublayer) such as DHCP, layer 2 mode is a good choice.

The qeth device driver default for OSA devices is now layer 2 mode. To continue using the previous default of layer 3 mode, set LAYER2='0' explicitly.

VSWITCH='value'

Where value can be 0 or 1.

Specify VSWITCH='1' when connecting to a z/VM VSWITCH or GuestLAN, or VSWITCH='0' (or nothing at all) when using directly attached real OSA or directly attached real HiperSockets.

MACADDR='MAC_address'

When you specify LAYER2='1' and VSWITCH='0', optionally use this parameter to specify the MAC address. Linux needs six colon-separated octets and lower case hex digits. Note that this is different from the z/VM notation, so be careful if you copy and paste information from z/VM.

If you specify LAYER2='1' and VSWITCH='1', you must not specify the MACADDR, because z/VM assigns a unique MAC address to virtual network devices in layer 2 mode.

CTCPROT='value'

Where value can be 0, 1, or 3.

Specifies the CTC protocol for NETTYPE='ctc'. The default is 0.

HOSTNAME='string'

Where string is the hostname of the newly-installed Linux instance.

IPADDR='IP'

Where IP is the IP address of the new Linux instance.

NETMASK='netmask'

Where netmask is the netmask.

The netmask supports the syntax of a prefix integer (from 1 to 32) as specified in IPv4 classless interdomain routing (CIDR). For example, you can specify 24 instead of 255.255.255.0, or 20 instead of 255.255.240.0.

GATEWAY='gw'

Where gw is the gateway IP address for this network device.

MTU='mtu'

Where mtu is the Maximum Transmission Unit (MTU) for this network device.

DNS='server1:server2:additional_server_terms:serverN'

Where 'server1:server2:additional_server_terms:serverN' is a list of DNS servers, separated by colons. For example:

DNS='10.1.2.3:10.3.2.1'

SEARCHDNS='domain1:domain2:additional_dns_terms:domainN'

Where 'domain1:domain2:additional_dns_terms:domainN' is a list of the search domains, separated by colons. For example:

SEARCHDNS='subdomain.domain:domain'

You only need to specify SEARCHDNS= if you specify the DNS= parameter.

DASD=

Defines the DASD or range of DASDs to configure for the installation. For a detailed description of the syntax, refer to the dasd_mod device driver module option described in the chapter on the DASD device driver in Linux on System z Device Drivers, Features, and Commands on Red Hat Enterprise Linux 6.

Linuxrc supports a comma-separated list of device bus IDs or of ranges of device bus IDs with the optional attributes ro, diag, erplog, and failfast. Optionally, you can abbreviate device bus IDs to device numbers with leading zeros stripped. Any optional attributes should be separated by colons and enclosed in parentheses. Optional attributes follow a device bus ID or a range of device bus IDs.

The only supported global option is autodetect. This does not support the specification of non-existent DASDs to reserve kernel device names for later addition of DASDs. Use persistent DASD device names (for example /dev/disk/by-path/...) to enable transparent addition of disks later. Other global options such as probeonly, nopav, or nofcx are not supported by linuxrc.

Only specify those DASDs that you really need to install your system. All unformatted DASDs specified here must be formatted after a confirmation later on in the installer (refer to Section 23.6.1.1, "DASD low-level formatting"). Add any data DASDs that are not needed for the root file system or the /boot partition after installation as described in Section 25.1.3.2, "DASDs that are not part of the root file system".

For FCP-only environments, specify DASD='none'.

For example:

DASD='eb1c,0.0.a000-0.0.a003,eb10-eb14(diag),0.0.ab1c(ro:diag)'

FCP_n='device_bus_ID WWPN FCP_LUN'

Where:

n is typically an integer value (for example FCP_1 or FCP_2) but could be any string with alphabetic or numeric characters or underscores.
device_bus_ID specifies the device bus ID of the FCP device representing the host bus adapter (HBA) (for example 0.0.fc00 for device fc00).
WWPN is the world wide port name used for routing (often in conjunction with multipathing) and is as a 16-digit hex value (for example 0x50050763050b073d).
FCP_LUN refers to the storage logical unit identifier and is specified as a 16-digit hexadecimal value padded with zeroes to the right (for example 0x4020400100000000).

These variables can be used on systems with FCP devices to activate FCP LUNs such as SCSI disks. Additional FCP LUNs can be activated during the installation interactively or by means of a kickstart file. There is no interactive question for FCP in linuxrc. An example value may look similar to the following:

FCP_1='0.0.fc00 0x50050763050b073d 0x4020400100000000'

Important - values are site-specific

Each of the values used in the FCP parameters (for example FCP_1 or FCP_2) are site-specific and are normally supplied by the FCP storage administrator.

The installation program prompts you for any required parameters not specified in the parameter or configuration file except for FCP_n.

26.4. VNC and X11 parameters

The following parameters can be defined in a parameter file but do not work in a CMS configuration file. With these parameters you control what interface will be used for anaconda.

To use an X11 user interface without X11 forwarding, specify the following X11 parameter:

display=IP/hostname:display: Sets the hostname or IP address and the X11 display where the installer should connect to and display its graphical user interface.

To use a VNC server instead of an X11 user interface, specify the following VNC parameters:

vnc: Specify vnc to use the VNC graphical user interface later in the installation process.
vncpassword=: This parameter sets the password used to connect to the VNC server. The password parameter is optional. If not used, the VNC server does not use a password and anybody can connect to the VNC server.
vncconnect=IP/hostname[:port]: When used in addition to vnc and vncpassword=, this optional parameter specifies the hostname or IP address (and optionally, a TCP port) where a VNC client is running in listening mode. The installer connects to and displays its graphical user interface on this VNC client.

26.5. Loader parameters

The following parameters can be defined in a parameter file but do not work in a CMS configuration file.

To automate the loader screens, specify the following parameters:

lang=language: Sets the language of the installer user interface, for example, en for English or de for German. This automates the response to Choose a Language (refer to Section 22.3, "Language Selection").
repo=installation_source: Sets the installation source to access stage 2 as well as the repository with the packages to be installed. This automates the response to Installation Method (refer to Section 22.4, "Installation Method").

26.6. Parameters for kickstart installations

The following parameters can be defined in a parameter file but do not work in a CMS configuration file.

ks=URL: References a kickstart file, which usually resides on the network for Linux installations on System z. Replace URL with the full path including the file name of the kickstart file. This parameter activates automatic installation with kickstart. Refer to Section 28.4, "Automating the Installation with Kickstart" and Section 32.10, "Starting a Kickstart Installation" for more details.]
RUNKS=value: Where value is defined as 1 if you want to run the loader automatically on the Linux console without having to log in over the network with SSH. To use RUNKS=1, the console must either support full-screen or the cmdline option below should be used. The latter applies for the 3270 terminal under z/VM or the operating system messages console for LPAR. We recommend RUNKS=1 for fully automatic installations with kickstart. When RUNKS=1 is set, linuxrc automatically continues in case of parameter errors and does not interrupt unattended installations by prompting for user interaction.
Leave out the parameter or specify RUNKS=0 otherwise.
cmdline: When cmdline is specified, output on line-mode terminals (such as 3270 under z/VM or operating system messages for LPAR) becomes readable, as the installer disables escape terminal sequences that are only applicable to UNIX-like consoles. This requires installation with a kickstart file that answers all questions, since the installer does not support interactive user input in cmdline mode.

Ensure that your kickstart file contains all required parameters before you use either the RUNKS or cmdline options. Refer to Chapter 32, Kickstart Installations for details.

26.7. Miscellaneous parameters

The following parameters can be defined in a parameter file but do not work in a CMS configuration file.

askmethod: Do not use an automatically detected DVD as installation source but ask for the installation method to manually specify the installation source. This parameter is useful if you booted from an FCP-attached DVD but want to continue with another installation source, for example on the network or on a local hard disk.
mediacheck: Turns on testing of an ISO-based installation source; for example, when booted from an FCP-attached DVD or using repo= with an ISO on local hard disk or mounted with NFS.
nompath: Disables support for multi-pathing devices.
proxy=[protocol://][username[:password]@]host[:port]: Specify a proxy to use with installation over HTTP, HTTPS, or FTP.
rescue: Boot into a rescue system running from a ramdisk that can be used to fix and restore an installed system.
stage2=URL: Specifies a path to an install.img file instead of to an installation source. Otherwise, follows the same syntax as repo=. If stage2 is specified, it typically takes precedence over other methods of finding install.img. However, if anaconda finds install.img on local media, the stage2 URL will be ignored.
If stage2 is not specified and install.img cannot be found locally, anaconda looks to the location given by repo= or method=.
If only stage2= is given without repo= or method=, anaconda uses whatever repos the installed system would have enabled by default for installation.
syslog=IP/hostname[:port]: Makes the installer send log messages to a remote syslog server.

The boot parameters described here are the most useful for installations and trouble shooting on System z, but only a subset of those that influence the installer. Refer to Chapter 28, Boot Options for a more complete list of installer boot parameters.

26.8. Sample parameter file and CMS configuration file

To change the parameter file, begin by extending the shipped generic.prm file.

Example of generic.prm file:

root='/dev/ram0' ro ip='off' ramdisk_size='40000' cio_ignore='all,!0.0.0009'CMSDASD='191' CMSCONFFILE='redhat.conf'vnc

Example of redhat.conf file configuring a QETH network device (pointed to by CMSCONFFILE in generic.prm):

NETTYPE='qeth'SUBCHANNELS='0.0.0600,0.0.0601,0.0.0602'PORTNAME='FOOBAR'PORTNO='0'LAYER2='1'MACADDR='02:00:be:3a:01:f3'HOSTNAME='foobar.systemz.example.com'IPADDR='192.168.17.115'NETMASK='255.255.255.0'GATEWAY='192.168.17.254'DNS='192.168.17.1'SEARCHDNS='systemz.example.com:example.com'DASD='200-203'

Installation Guide

Chapter 26. Parameter and Configuration Files

26.1. Required parameters

26.2. The z/VM configuration file

26.3. Installation network parameters

26.4. VNC and X11 parameters

26.5. Loader parameters

26.6. Parameters for kickstart installations

26.7. Miscellaneous parameters

26.8. Sample parameter file and CMS configuration file

Chapter 27. IBM System z References

27.1. IBM System z Publications

27.2. IBM Redbooks publications for System z

27.3. Online resources