Kickstart parameter --ethtool is ignored

Solution Verified - Updated -

Environment

  • Red Hat Enterprise Linux (RHEL) 7, 8

Issue

The --ethtool parameter in network ... --ethtool="..." is ignored.
The option ETHTOOL_OPTS="..." added into the resulting /etc/sysconfig/network-scripts/ifcfg-ens1 is also ignored.

Resolution

Workaround - create a dispatcher script for NetworkManager

Excerpt of the kickstart configuration file creating the dispatcher script:

%post

ETHTOOL=/etc/NetworkManager/dispatcher.d/30-ethtool
INTERFACE=ens1

echo -e '#!/bin/bash

if [ "$1" == "'$INTERFACE'" ] && [ "$2" == "up" ]; then
    ethtool -G $1 rx 2047 tx 511
fi' > $ETHTOOL

chmod +x $ETHTOOL

%end

man NetworkManager contains more detailed information

After the first reboot, we see the output of the ethtool command:

# ethtool -g ens1
Ring parameters for ens1:
Pre-set maximums:
RX:             4096
RX Mini:        0
RX Jumbo:       0
TX:             4096
Current hardware settings:
RX:             2048
RX Mini:        0
RX Jumbo:       0
TX:             512

SELinux context is set correctly:

# ls -Z /etc/NetworkManager/dispatcher.d/
-rwxr-xr-x. root root system_u:object_r:NetworkManager_initrc_exec_t:s0 00-netreport
-rwxr-xr-x. root root system_u:object_r:NetworkManager_initrc_exec_t:s0 11-dhclient
-rwxr-xr-x. root root system_u:object_r:NetworkManager_initrc_exec_t:s0 20-chrony
-rwxr-xr-x. root root system_u:object_r:NetworkManager_initrc_exec_t:s0 30-ethtool
drwxr-xr-x. root root system_u:object_r:NetworkManager_initrc_exec_t:s0 no-wait.d
drwxr-xr-x. root root system_u:object_r:NetworkManager_initrc_exec_t:s0 pre-down.d
drwxr-xr-x. root root system_u:object_r:NetworkManager_initrc_exec_t:s0 pre-up.d

The script /etc/NetworkManager/dispatcher.d/30-ethtool created from the kickstart looks like this:

#!/bin/bash

if [ "$1" == "ens1" ] && [ "$2" == "up" ]; then
    ethtool -G $1 rx 2047 tx 511
fi

Root Cause

This is known bug currently tracked by BZ 1762749 (RHEL7).
This is known bug currently tracked by BZ 1886381 (RHEL8).

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