11.2. Understanding the Device Renaming Procedure
The device name procedure in detail is as follows:
- A rule in
/usr/lib/udev/rules.d/60-net.rules
instructs the udev helper utility, /lib/udev/rename_device, to look into all/etc/sysconfig/network-scripts/ifcfg-suffix
files. If it finds anifcfg
file with aHWADDR
entry matching the MAC address of an interface it renames the interface to the name given in theifcfg
file by theDEVICE
directive. - A rule in
/usr/lib/udev/rules.d/71-biosdevname.rules
instructs biosdevname to rename the interface according to its naming policy, provided that it was not renamed in a previous step, biosdevname is installed, andbiosdevname=0
was not given as a kernel command on the boot command line. - A rule in
/lib/udev/rules.d/75-net-description.rules
instructs udev to fill in the internal udev device property values ID_NET_NAME_ONBOARD, ID_NET_NAME_SLOT, ID_NET_NAME_PATH, ID_NET_NAME_MAC by examining the network interface device. Note, that some device properties might be undefined. - A rule in
/usr/lib/udev/rules.d/80-net-name-slot.rules
instructs udev to rename the interface, provided that it was not renamed in step 1 or 2, and the kernel parameternet.ifnames=0
was not given, according to the following priority: ID_NET_NAME_ONBOARD, ID_NET_NAME_SLOT, ID_NET_NAME_PATH. It falls through to the next in the list, if one is unset. If none of these are set, then the interface will not be renamed.
Steps 3 and 4 are implementing the naming schemes 1, 2, 3, and optionally 4, described in Section 11.1, “Naming Schemes Hierarchy”. Step 2 is explained in more detail in Section 11.6, “Consistent Network Device Naming Using biosdevname”.