[kde-linux] Display of network activity quit working.

[Duncan]

James Tyrer posted on Tue, 25 Jun 2013 14:22:44 -0700 as excerpted:

> I am just finishing up with updating to 4.10.3 if that matters.
> Somewhere before that, the display of my network activity quit working.
>   I think that it might have been exactly when my Ethernet ports were
> assigned new and strange names.  I now have two named:
> 
> 	enp5s12 enp0s18

Umm... you can thank systemd's udev for that.  (Whether Lennart actually 
had anything to do with it or not I'm not sure, but it does feel like the 
sort of stuff he tends to do.)

They apparently "decided" that the traditional/default-kernel style eth* 
and wlan* interface names weren't confusing enough, and that names that 
looked like some sort of ascii-armored encryption were far more useful.

The official explanation is that the new names are more stable or at 
least predictable, which they arguably could be for people who have 
several such interfaces and keep swapping them out.  What they apparently 
forgot is the vast numbers of people who only have a single ethernet 
interface and/or a single wlan interface, who are unlikely to ever change 
it unless it breaks and they replace it, in which case the names stayed 
the same before (eth0, wlan0), but are now likely to change.

http://www.google.com/search?q=systemd+network+interface+names

As several of those first-page google hits should point out, the names 
above stand for en=ethernet, p#=pci-bus-number, s#=slot-number.

And at least it's relatively easy to either disable the new naming and go 
back to the old naming, or assign your own stable names as desired:

Something like this as /etc/udev/rules.d/70-persistent-net.rules should 
assign your chosen name (as one line):

SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}
=="00:01:02:03:04:05", ATTR{dev_id}=="0x0", ATTR{type}=="1", 
KERNEL=="eth*", NAME="eth00"

* address is the MAC address, the operational selector in the above.  
Obviously change it as necessary.

* name is the chosen name, DO NOT DUPLICATE A DEFAULT KERNEL NAME (so 
eth0 is out, thus eth00 in the above example).


Alternatively, simply disable the new-style udev names and let the kernel 
assign default kernel names as it would without udev.  To do this, create 
a file of the same name as the default udev rule (AFAIK shipped as
80-net-name-slot.rules), but in a location (like /etc/udev/rules.d) that 
overrides the shipped-default rule (often in (/usr)?/lib/udev/rules.d), 
without any active rules to replace the ones being overridden so the the 
kernel names get activated.


So a file /etc/udev/rules.d/80-net-name-slot.rules

... that's empty except for #-comment lines should return to kernel 
defaults (note that the freedesktop.org link wraps as posted, fix that if 
pasting into a file of your own):


# /etc/udev/rules.d/80-net-name-slot.rules

# This file blocks udev-197+ default predictable network interface names.
# mv to ! *.rules or rm and reboot to activate.

# http://www.freedesktop.org/wiki/Software/systemd/
PredictableNetworkInterfaceNames

# To check new udev-default net ifnames:
# udevadm test-builtin net_id /sys/class/net/<ifname>
# example: enp4s0 (ethernet, pci-bus 4 slot 0)



> as well as a name:
> 
> 	sit0
> 
> which I am guessing is the loop back.
> 
> "Network History" in "System Monitor" indicates that it has
> automatically configured itself to show all three, but it shows nothing
> -- no activity on any of them.  The Plasma Widget has a choice and I
> think that I have the correct one selected but it shows nothing also.
> 
> I am especially puzzled as to how the "System Monitor" found these but
> doesn't display them.

Probably the code knows where to look for the names using kernel 
functionality, but has a filter based on the old names that doesn't 
recognize the new ones yet, so they show up but don't actually register 
any activity.

Simply reverting to more traditional names using one of the two above 
options so the filter recognizes them, will hopefully do the trick.  
Alternatively, a patch shouldn't be /too/ difficult to hack up if indeed 
the only problem is a name-pattern filter as I suspect is likely.  I'd 
guess/hope they've done that already for 4.11, but meanwhile...

-- 
Duncan - List replies preferred.   No HTML msgs.
"Every nonfree program has a lord, a master --
and if you use the program, he is your master."  Richard Stallman