On Jan 30, 2020, at 04:48 PM, Bob Weber <bobrweber@gmail.com> wrote:"Example 3. Debugging NamePolicy= assignments" near the bottom of the page at "https://www.freedesktop.org/software/systemd/man/systemd.link.html"Yeah. That's one I looked at. The one with the table of the Ethernet speeds and duplexity. And the list and descriptions of data that're sometimes needed in the file. I'll look at this again tomorrow, Bob, but I'm really not impressed with the way systemd is setting up the Ethernet interfaces. Like I said before, "Counting Ethernet interfaces isn't rocket science." But it can be made so if you make things complex and spread the config over several dirs and several files, some of which are explained in the dox but turn out not to exist on my Buster disk. Somehow, back in the eth days, the data in Debian's /etc/network/interfaces file was enough to get networking going. Then, on an Ethernet network, the Ethernet chips pretty well figured out the best speed and duplex all by themselves as soon as they connected to something.This nameing configuration has worked on 5 Debian systems all running updated testing.And counting interfaces has worked for me for a couple decades, on many systems and several OSs. But I'll find your earlier email and try systemd one more time. It'd be nice for the interface names to be, as systemd calls it, 'consistent.' And, FWIF, I appreciate your help and advice...
I just ran a test on a VM that I installed last week so it is
pretty much up to date. I ran the command "ip a" which gave me
the current undesirable name "enp1s0" and MAC address.
First I created /etc/systemd/network/10-eth0.link using the MAC address and the name eth0. If the MAC changes then there are other characteristics to add to the [Match] section to uniquely define the port (see above link).
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root@debian-ZFS ~ # cat /etc/systemd/network/10-eth0.link
[Match]
MACAddress=52:54:00:ea:e3:53
[Link]
Name=eth0
Second I linked the default to /dev/null.
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link -s /dev/null /etc/systemd/network/99-Default.link
Next I ran the test command from Example 3 at the above link to see what udevadm thinks.
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SYSTEMD_LOG_LEVEL=debug udevadm test-builtin net_setup_link
/sys/class/net/enp1s0
Trying to open "/etc/systemd/hwdb/hwdb.bin"...
Trying to open "/etc/udev/hwdb.bin"...
Trying to open "/usr/lib/systemd/hwdb/hwdb.bin"...
Trying to open "/lib/systemd/hwdb/hwdb.bin"...
Trying to open "/lib/udev/hwdb.bin"...
=== trie on-disk ===
tool version: 244
file size: 10287564 bytes
header size 80 bytes
strings 2145012 bytes
nodes 8142472 bytes
Load module index
Found container virtualization none.
timestamp of '/etc/systemd/network' changed
Parsed configuration file /usr/lib/systemd/network/99-default.link
Skipping empty file: /etc/systemd/network/99-Default.link
Parsed configuration file
/usr/lib/systemd/network/73-usb-net-by-mac.link
Parsed configuration file /etc/systemd/network/10-eth0.link
Created link configuration context.
ID_NET_DRIVER=virtio_net
enp1s0: Config file /etc/systemd/network/10-eth0.link is applied
ethtool: autonegotiation is unset or enabled, the speed and duplex
are not writable.
enp1s0: Device has name_assign_type=4
Using default interface naming scheme 'v243'.
enp1s0: Policies didn't yield a name, using specified Name=eth0.
ID_NET_LINK_FILE=/etc/systemd/network/10-eth0.link
ID_NET_NAME=eth0
Unload module index
Unloaded link configuration context.
Notice the ID_NET_NAME=eth0 is what I wanted. Also option to the
udevadm command /sys/class/net/enp1s0 contains the current
undesirable name of the interface (enp1s0).