/usr/share/systemd/write_persistent_net_s390x_virtio is in udev 237-3ubuntu10.
This file is owned by root:root, with mode 0o755.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 | #!/bin/sh
set -e
#
# udevd since 232-20 learned to generate stable interface names for network
# interfaces in kvm/qemu. However, existing machines upgrading will be using
# the ethX names instead. The most risk-averse action is to encode
# "persistent-net-rules" like rules to keep the ethX names on upgrades, since
# the interface names (ethX) may be in use not only in /etc/network/interfaces
# but in other configurations too (daemons, firewalls, etc).
#
# This is a one time action, and can be removed after the next stable & LTS
# releases. (~ May 2018)
#
rulesfile=/etc/udev/rules.d/70-persistent-net.rules
if [ `uname -m` != 's390x' ]
then
exit 0
fi
if [ `systemd-detect-virt` != 'kvm' ]
then
exit 0
fi
if [ -f $rulesfile ]
then
exit 0
fi
for interface in /sys/class/net/eth*
do
[ -d $interface ] || continue
name=$(basename $interface)
address=$(cat $interface/address)
cat <<EOF >>$rulesfile
SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="$address", KERNEL=="eth*", NAME="$name"
EOF
done
|