systemd-udevd: Could not generate persistent MAC address for br0: No such file or directory
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SUSE Linux Enterprise Server 15
journalctl -b0 -u systemd-udevd | grep MAC May 11 11:09:16 server15 systemd-udevd: Could not generate persistent MAC address for br0: No such file or directory May 11 11:09:16 server15 systemd-udevd: Could not generate persistent MAC address for bond1: No such file or directory
Create a systemd link file called /etc/systemd/network/98-default.link. Which matches on drivers and set the MACAddressPolicy to none.
Use ethtool -i <device> to expose the driver.
server15:~ # ethtool -i br0 driver: bridge version: 2.3 firmware-version: N/A expansion-rom-version: bus-info: N/A supports-statistics: no supports-test: no supports-eeprom-access: no supports-register-dump: no supports-priv-flags: no server15:~ # ethtool -i bond1 driver: bonding version: 3.7.1 firmware-version: 2 expansion-rom-version: bus-info: supports-statistics: no supports-test: no supports-eeprom-access: no supports-register-dump: no supports-priv-flags: no
In this example the file will look as follows:
server15:~ # cat /etc/systemd/network/98-default.link [Match] Driver=bonding bridge [Link] MACAddressPolicy=none
For interfaces that doesn't have a persistent MAC address (most hardware should) a new MAC address is generated which is guaranteed to be the same on every boot for the given machine and the given device, but which is otherwise random. The option MACAddressPolicy=persistent enables this by default in /usr/lib/systemd/network/99-default.link.
This feature depends on ID_NET_NAME_* properties to exist for the link. On virtual interfaces (such as bridges, bonds, etc...) these properties are not set hence the generation of a persistent MAC address will fail with:
"Could not generate persistent MAC address for $name: No such file or directory"See for more information "man systemd.link"
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- Document ID:000020260
- Creation Date: 02-Jun-2021
- Modified Date:02-Jun-2021
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