Chapter 21. Installation Phase 1: Configuring a Network Device

After the kernel boot, you will configure one network device using the linuxrc program. This network device is needed to complete the installation. If you are installing interactively (with the default parameter file generic.prm), you will be asked questions about your network. It is a good idea to have your data ready in the form of a datasheet or similar. If you want to automate this step, supply the information for each option in your parameter file or CMS configuration file.
As an example, let us look at how to configure an OSA network adapter under z/VM. When linuxrc starts, you see the following message: 
Starting the zSeries initrd to configure networking. Version is 1.2
Starting udev...
Network devices are sensed and listed. The list of devices depends on the cio_ignore kernel parameter used. If no devices are found because of cio_ignore, as in the example below, you can clear the list of ignored devices. Note that this might take some time and result in a long list when there are many devices, such as on an LPAR. 
Scanning for available network devices...
Autodetection found 0 devices.
Note: There is a device blacklist active! (Clearing might take long)
c) clear blacklist, m) manual config, r) rescan, s) shell:
c
Clearing device blacklist...
Scanning for available network devices...
Autodetection found 14 devices.
 
NUM CARD CU CHPID TYPE DRIVER IF DEVICES
 1 OSA (QDIO) 1731/01 00 OSD qeth eth 0.0.f500,0.0.f501,0.0.f502
 2 OSA (QDIO) 1731/01 01 OSD qeth eth 0.0.f503,0.0.f504,0.0.f505
 3 OSA (QDIO) 1731/01 02 OSD qeth eth 0.0.1010,0.0.1011,0.0.1012
 4 HiperSockets 1731/05 03 IQD qeth hsi 0.0.1013,0.0.1014,0.0.1015
 5 OSA (QDIO) 1731/01 04 OSD qeth eth 0.0.1017,0.0.1018,0.0.1019
 6 CTC adapter 3088/08 12 ? ctcm ctc 0.0.1000,0.0.1001
 7 escon channel 3088/1f 12 ? ctcm ctc 0.0.1002,0.0.1003
 8 ficon channel 3088/1e 12 ? ctcm ctc 0.0.1004,0.0.1005
 9 OSA (QDIO) 1731/01 76 OSD qeth eth 0.0.f5f0,0.0.f5f1,0.0.f5f2
 10 LCS OSA 3088/60 8a OSE lcs eth 0.0.1240,0.0.1241
 11 HiperSockets 1731/05 fb IQD qeth hsi 0.0.8024,0.0.8025,0.0.8026
 12 HiperSockets 1731/05 fc IQD qeth hsi 0.0.8124,0.0.8125,0.0.8126
 13 HiperSockets 1731/05 fd IQD qeth hsi 0.0.8224,0.0.8225,0.0.8226
 14 HiperSockets 1731/05 fe IQD qeth hsi 0.0.8324,0.0.8325,0.0.8326
 
<num>) use config, m) manual config, r) rescan, s) shell:
Enter the number of the configuration you want to use, for example 9. Selecting from the table provides the installer with information for the type of network device and the device addresses for its subchannels. Alternatively, you can enter m and proceed to enter the network type (qeth), the read, write, data channels, and the OSA port. Accept defaults by pressing Enter; under z/VM you might need to press Enter twice. 
m
 
* NOTE: To enter default or empty values press enter twice. *
 
 
Network type (qeth, lcs, ctc, ? for help). Default is qeth:
qeth
 
Read,write,data channel (e.g. 0.0.0300,0.0.0301,0.0.0302 or ? for help).
0.0.f5f0,0.0.f5f1,0.0.f5f2
 
Portname (1..8 characters, or ? for help). Default is no portname:
 
 
Relative port number for OSA (0, 1, or ? for help). Default is 0:
 
 
 
Activating network device...
Detected: OSA card in OSD mode, Gigabit Ethernet
Then questions pertaining to your Linux instance are displayed: 
 Hostname of your new Linux guest (FQDN e.g. s390.redhat.com or ? for help):
host.subdomain.domain

IPv4 address / IPv6 addr. (e.g. 10.0.0.2 / 2001:0DB8:: or ? for help)
10.0.0.42
 
IPv4 netmask or CIDR prefix (e.g. 255.255.255.0 or 1..32 or ? for help). Default is 255.0.0.0:
24
 
IPv4 address of your default gateway or ? for help:
10.0.0.1
Trying to reach gateway 10.0.0.1...
 
IPv4 addresses of DNS servers (separated by colons ':' or ? for help):
10.1.2.3:10.3.2.1
Trying to reach DNS servers...
 
DNS search domains (separated by colons ':' or ? for help):
subdomain.domain:domain
 
DASD range (e.g. 200-203,205 or ? for help). Default is autoprobing:
eb1c
Activated DASDs:
0.0.eb1c(ECKD) dasda : active, blocksize: 4096, 1803060 blocks, 7043 MB

Important

The installer requires the definition of a DASD. For a SCSI-only installation, enter none. This satisfies the requirement for a defined DASD parameter, while resulting in a SCSI-only environment.
If you make a mistake, the dialog either notices the error and asks you to re-enter the parameter, or you can go back later to restart the dialog: 
 Incorrect ... (<OPTION-NAME>):
0) redo this parameter, 1) continue, 2) restart dialog, 3) halt, 4) shell
When you restart the dialog, it remembers what you entered before: 
 Network type
0) default is previous "qeth", 1) new value, ?) help
At the end of the configuration, you see the message Initial configuration completed: 
 Initial configuration completed.
 
c) continue, p) parm file/configuration, n) network state, r) restart, s) shell
You can now check your network configuration by entering n: 
 n
eth0 Link encap:Ethernet HWaddr 02:00:00:AB:C9:81
 inet addr:10.0.0.42 Bcast:10.0.0.255 Mask:255.255.255.0
 UP BROADCAST RUNNING MULTICAST MTU:1492 Metric:1
 RX packets:64 errors:0 dropped:0 overruns:0 frame:0
 TX packets:4 errors:0 dropped:0 overruns:0 carrier:0
 collisions:0 txqueuelen:1000
 RX bytes:3334 (3.2 KiB) TX bytes:336 (336.0 b)
 
lo Link encap:Local Loopback
 inet addr:127.0.0.1 Mask:255.0.0.0
 UP LOOPBACK RUNNING MTU:16436 Metric:1
 RX packets:0 errors:0 dropped:0 overruns:0 frame:0
 TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
 collisions:0 txqueuelen:0
 RX bytes:0 (0.0 b) TX bytes:0 (0.0 b)
 
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
127.0.0.1 0.0.0.0 255.255.255.255 UH 0 0 0 lo
10.0.0.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0
0.0.0.0 10.0.0.1 0.0.0.0 UG 0 0 0 eth0
 
c) continue, p) parm file/configuration, n) network state, r) restart, s) shell
If you want to change something, enter r to restart the dialog. To show the parameters as specified in a parameter or configuration file or interactively enter p. You can then copy the output from your terminal and paste it into an editor to save it to disk on your local workstation. You can use the copy as a template for a parameter or configuration file for future installations: 
 p
 
NETTYPE=qeth
IPADDR=10.0.0.42
NETMASK=255.255.255.0
GATEWAY=10.0.0.1
HOSTNAME=host.subdomain.domain
SUBCHANNELS=0.0.f5f0,0.0.f5f1,0.0.f5f2
LAYER2=1
MACADDR=02:00:00:AB:C9:81
PORTNAME=OSAPORT
DNS=10.1.2.3:10.3.2.1
SEARCHDNS=subdomain.domain:domain
DASD=eb1c
 
c) continue, p) parm file/configuration, n) network state, r) restart, s) shell
Again, to change something, restart the dialog with r. Finally, if all is in order, enter c to continue: 
 c
 
Starting sshd to allow login over the network.
 
Connect now to 10.0.0.42 and log in as user 'install' to start the
installation.
E.g. using: ssh -x install@10.0.0.42
For VNC or text mode, disable X11 forwarding (recommended) with 'ssh -x'.
For X11, enable X11 forwarding with 'ssh -X'.
 
You may log in as the root user to start an interactive shell.
The preliminary network setup is now complete and the installer starts an SSH daemon. You can log into your Linux instance over SSH. If you are using RUNKS=1 with kickstart and cmdline mode, linuxrc automatically starts the loader.

21.1. A Note on Terminals

During the installation, the installation program displays messages on a line-mode terminal. This is the HMC Operating System Messages applet if you install under LPAR, or a 3270 terminal if you install under z/VM.
Linuxrc provides a rescue shell on the line-mode terminal. Press the Enter key (twice under z/VM) to start the shell. You cannot use full-screen applications such as the vi editor on the line-mode terminal. Switch to line-mode based editors such as ed, ex, or sed to edit text files if necessary.
Be aware that long-running commands might not be interruptible with the escape sequence Ctrl+C. Call commands with options that make them return in time voluntarily. The shell on the 3270 terminal is available throughout the whole installation process until the point where the system needs to reboot.
Once the shell has been provided, you may exit with an error level of zero to get a new shell instance replacing the old one, or you may exit with an error level different from zero to force a shutdown of the installation system.
Connect to the installed system using user root to get a root shell without automatically starting the installer. For problem determination, you might connect with many ssh sessions.