Postings by Volker Wysk

LVM: How to access a foreign volume group


I'm about to set up an LVM cache (for my encrypted root file system). This involves attaching a cache pool LV to the origin LV to be cached, as the last step:

lvconvert --type cache --cachepool kubuntu-vg/cachedatalv kubuntu-vg/root

I've got it working in a virtual machine, but I'm hesitant to apply the procedure to my production system. It would be bad, if I had to restore it from a backup, because I have installed and configured a lot of things.

So, in case something goes wrong, I want to be able to start a rescue system and undo the attaching of the cache pool LV to the origin LV.

Kubuntu-PPAs for Artful


I've done a "do-release-upgrade" from 17.04 to 17.10, and I got the message
"Paketquellen von Drittanbietern deaktiviert" ("package sources for thrid
party providers deactivated").

It turns out, that it has rewritten my Kubuntu PPAs in /etc/apt/
sources.list.d/ from "zesty" to "artful", and at the same time commented out
these lines:

# deb <a href="" title=""></a> artful main


# deb <a href="" title=""></a> artful main

How do I configure the new Kubuntu PPAs, for Artful?

(Solved) It's All Text vs. Textern in Firefox 57


I'm writing this message for folks, which encounter the same problem with Firefox 57, that I did.

You heard of it: There is a big retrofit to Firefox in Version 57. This means that many addons don't work any longer and need to be ported to the new firefox version. (Addons now need to use the WebExtensions API).

There's the It's All Text addon, which I've used up to firefox version 56. It has been used to launch an external text editor for editing text areas. It doesn't work with Firefox 57.

(Solved) Internet is dying


I've connected my desktop to the router with the new cable, for some
17 hours now. (Had to squeeze the cable....) The laptop isn't involved
now, and there habe been no occurrences in the output of ping at all.

I don't know, what had been wrong. Is it the cable? The cable only?
It seemed like the router was broken.

I'll leave it at that, although there are unanswered questions, and

Thank you, to Xen and Colin Law, amongst others, who helped me.


Internet is dying - or is it..?


I'ts stupid. When you want things to work, they're broken. When you want them
to be broken, they work! Well, mostly.

I've purchased a new network cable, and am running ping on both of my machines
(desktop and laptop), for some 14 hours now. Both are connected by cable, with
the desktop (with broken internet connection before) using the new cable, and
the laptop using the old one.

I've written a little program which executes a command and prefixes each line
of its output with a timestamp. The command is "ping -i20".

slow ubuntu-users list


This list seems to have gotten very slow. It took almost an hour, before I
received Xen's last message. It showed up in the archives, before I received
it, which seem to be updated every half hour.

- Something should be done about it.
- It's probably not an error on your side.

Keep hacking,

Re: Re: Internet is dying - diagnostics

Am 21.10.2017 um Uhr haben Sie geschrieben:
I've put this in my resolv.conf for now:

# Dynamic resolv.conf(5) file for glibc resolver(3) generated by

This should be enough for trying it. If it works, I'll need to place
that (google's DNS) there permanently. My machine (my desktop)
is a Kubuntu 16.04.

Re: Re: Re: Internet is dying - diagnostics

Am 21.10.2017 um Uhr haben Sie geschrieben:
No, I've used traceroute6, that's different.

The connection isn't broken now, and now I get:

desktop ~ $ traceroute
traceroute to (, 30 hops max, 60 byte
1 ( 0.068 ms 0.025 ms 0.025 ms

desktop ~ $ traceroute
traceroute to (, 30 hops max, 60 byte
1 ( 0.068 ms 0.034 ms 0.025 ms

desktop ~ $ host

Re: Re: Internet is dying - diagnostics

Am 21.10.2017 um Uhr haben Sie geschrieben:
That's funny. No, I am not, and I wonder what that address
could be. It isn't listed in my router's web interface.

Internet is dying - diagnostics


Now the connection is down again. I'm writing this with my laptop and
webmail... Here are the diagnostics:



Internet is dying


The output of ifconfig:

enp2s0 Link encap:Ethernet Hardware Adresse 60:a4:4c:4e:17:47
inet Adresse: Bcast:
inet6-Adresse: fe80::967a:55d6:22b8:8659/64
RX-Pakete:11192 Fehler:0 Verloren:0 Überläufe:0 Fenster:0
TX-Pakete:12444 Fehler:0 Verloren:0 Überläufe:0 Träger:0
Kollisionen:0 Sendewarteschlangenlänge:1000
RX-Bytes:3562092 (3.5 MB) TX-Bytes:2277867 (2.2 MB)

lo Link encap:Loka

Internet is dying


My internet connection has become fickle. It happens that there suddenly is no
more internet connection at all. When I "ping" some site, then there is no
output at all. KDE say that the IP of my machine can't be acquired. Then I
can't contact my laptop, which is connected to the same router, either. Not
even my dynamic DNS address (same machine) can be accessed.

Again: "Somebody knows your password" (Google)


Google notifies me by mail that a log in attempt, with my password, has been
prevented, because of the device being unknown.

I've already had this problem some two months ago.

Unlocking several crypto discs during boot


I have two crypto discs in my machine: the hard drive, and an SSD, which I
want to use as a cache for the former. This means that I have to enter two
passwords at boot time, even if they are the identical.

I'd like to file a feature request. When the passwords are identical, only one
should be requested. Which package should I specify for the bug report?


GRUB question


I'm trying to set up an SSD cache for my hard disk. Just in a virtual machine,
so far.

It's for my (encrypted) root filesystem. According to the instructions
(<a href="" title=""></a>), the
following is needed when the root filesystem is to be cached. Otherwise, it
won't be able to boot:

echo "dm_cache" >> /etc/initramfs-tools/modules
echo "dm_cache_mq" >> /etc/initramfs-tools/modules
echo "dm_persistent_data" >> /etc/initramfs-tools/modules
echo "dm_bufio" >> /etc/initramfs-tools/modules

Now, how do I make this take effect?

measuring disk i/o performance


I'm about to install an SSD (as a cache for my hard disk). Does someone know a
good tool for measuring the disk i/o speed?


Two ubuntu bugs


I wanna report two bugs in (K)Ubuntu 17.04.

The first one is in the (K)Ubuntu installer. When you enter the new passphrase,
the keyboard is still in English localization. When you're German, this means
(among other things) that the keys Z and Y are interchanged. When you log in,
after the install, the keyboard has been localized.

The second one is the "ubuntu-bug" program.

Upgrade path from MySQL to MariaDB broken? (Akonadi)


I'm trying to install Nextcloud. I'm following the instructions in the
Nextcloud 12 Server Administration Manual, Installation on Linux:
<a href="" title=""></a>

According to these instructions, mariadb-server needs to be installed.

(OT) Google: "Somebody knows your password"


I've received a mail titled "Jemand kennt Ihr Passwort" ("somebody knows your
password") from Google, and a "security warning" mail, with the same contents.

Somebody tried to access my google account with my password, from an (to
google) unknown device. The login was blocked, because of the device being
unknown to google. I was then guided to change my password, which I did.

Network comprehension question: localhost vs. local IP address


The Moinmoin wiki server can be run without configuration, so you can try it,
without the hasszle of configuring everything for Apache. It starts a server at
localhost:8080. This works.

Now I want to try if it works well with my smartphone. I try the address
<a href="" title=""></a>.

What happened to ubuntu-users?

No new mail in four days, archives ending at the same point in time ... -


Shared library not found


I have a stupid question. I've compiled and installed dspam from the sources,
since I want to integrate a spam filter in my Dovecot mail server (dovecot-

Kubuntu PPA doesn't work


Of the two Kununtu PPAs, one doesn't work for me:

~ % apt update
OK:1 <a href="" title=""></a> xenial InRelease
Holen:2 <a href="" title=""></a> xenial-updates InRelease [95,7 kB]
OK:3 <a href="" title=""></a> xenial-security InRelease
OK:4 <a href="" title=""></a> xenial InRelease
Ign:5 <a href="" title=""></a> xenial InRelease
OK:6 <a href="" title=""></a> xenial-backports In

Does my machine send spam???


I've got six messages, which say, that some spam message can't be delivered.
I've attached one of them.

I've had attacks on my local Dovecot mail server, but they should have been
blocked by fail2ban - ?.

Has my machine been hijacked to send spam?? What can I do?


Volatile certificates?


I've configured fetchmail to fetch my mail from four mail servers, amongst them and I'm using SSL to secure the connection.

This means, that the two certificates of the mentioned mail servers must be
checked. I lack the necessary root and intermediate certificates, for testing
the certfificate chain. So I must trust the two presented certificates, once. I
added the fingerprints of the certificates in my fetchmairc file, using the
directive "sslfingerprint".

That worked fine, for a few days.

Einbruchversuch in meinen Rechner ...??


Ich bekomme in der /var/log/auth.log eine Menge Meldungen, die so aussehen:

Testing an SD card


I have an SD card for my smartphone which I suspect to be defect. Is there a
command to test this? (I can copy it with dd to a file, so far it works.)


Testing an SD card


I have an SD card for my smartphone which I suspect to be defect. Is there a
command to test this? (I can copy it with dd to a file, so far it works.)


"404 Not Found" when doing "apt-get update"


I'm tyring to do a "apt-get update", and it mostly works.