Chapter 10. Configuring a persistent qeth device on IBM Z
Channel-based network interfaces on the IBM Z platform are virtualized and not automatically visible to RHEL when attached to your logical partition (LPAR) or z/VM guest. Before you can use the device in a network configuration, you must manually group subchannels into a single logical qeth device and activate it.
Prerequisites
- You defined the I/O subchannels and attached them to your LPAR or z/VM guest.
-
You installed the
s390utils-basepackage.
Procedure
Unmask the device IDs of the
qethdevice:If you know the device IDs, unmask these IDs. For example:
cio_ignore --remove 0.0.0600,0.0.0601,0.0.0602
# cio_ignore --remove 0.0.0600,0.0.0601,0.0.0602Copy to Clipboard Copied! Toggle word wrap Toggle overflow Specify the device IDs comma-separated as shown or as a range, for example
0.0.0600-0.0.0602.If you do not know the device IDs, you can unmask all IDs:
cio_ignore --remove-all
# cio_ignore --remove-allCopy to Clipboard Copied! Toggle word wrap Toggle overflow
Display the available
qethdevices:lszdev qeth
# lszdev qethCopy to Clipboard Copied! Toggle word wrap Toggle overflow TYPE ID ON PERS NAMES qeth 0.0.0600:0.0.0601:0.0.0602 no no
TYPE ID ON PERS NAMES qeth 0.0.0600:0.0.0601:0.0.0602 no noCopy to Clipboard Copied! Toggle word wrap Toggle overflow The output contains the following columns:
-
TYPE: Displays the device type. If you ranlszdev qeth, the command returns onlyqethdevices. -
ID: Displays the subchannel addresses of the hardware. This is a triplet of three hexadecimal addresses used for read, write, and data transfers. -
ON: Indicates the current operational state of the device wherenomeans that the driver has not yet grouped the channels and created a functional network device. -
PERS: Indicates the persistence status of the configuration wherenoconfirms that noudevdevice manager rule exists and, therefore, the device is not automatically be enabled after a reboot. -
NAMES: Displays the network interface name you can use in NetworkManager. If the field is empty, the channels have not been grouped or set online yet.
-
Create a
udevrule and activate theqethdevice:chzdev qeth 0.0.0600 -e
# chzdev qeth 0.0.0600 -eCopy to Clipboard Copied! Toggle word wrap Toggle overflow You can specify only the first address of a triplet, and the
chzdevutility automatically detects the associated write and data channels.
Verification
Verify the hardware state, and display the assigned interface name:
lszdev qeth TYPE ID ON PERS NAMES qeth 0.0.0600:0.0.0601:0.0.0602 yes yes enc600
# lszdev qeth TYPE ID ON PERS NAMES qeth 0.0.0600:0.0.0601:0.0.0602 yes yes enc600Copy to Clipboard Copied! Toggle word wrap Toggle overflow Ensure that both the
ONandPERScolumn returnyesfor your device. Note the interface name displayed in theNAMEScolumn. You require the name when you create a network configuration that uses this device.
Next steps
-
Use the
qethdevice in a network configuration, such as an Ethernet connection.