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Postings by Volker Wysk

Lots of kworkers

Hi

Every few days, I get a lot of kworkers (some 50) in the process list. The hard disk clatters all the time. From the web I've found that those are kernel threads. Since I have an SSD (apart from the harddisk, set up as a cache for the HD), this doesn't make my system unresponsive. But still...

What's going on here? And how to get rid of all those kworkers?

Bye
Volker

(solved) KDE root programs' fonts very small

Hi!

I've had the problem, that graphical programs (or program parts), which run as root, had a very small font size - such as systemsettings5 or muon's settings->configure software sources window.

I've investigated it, and I found that the following has to be added to /etc/environment:

XDG_CURRENT_DESKTOP=KDE

That is, the XDG_CURRENT_DESKTOP environment variable needs to be set to "KDE". But this doesn't work when set in ~/.bashrc, ~/.proile or /etc/profile. Looks like these scripts aren't called by kdesudo.

Tiny font in Synaptic

Hi!

I'm running a Kubuntu 16.04.3 LTS system. Reading the mailing list kubuntu-users (and ubuntu-users), made me want to try Synaptic. But the font is so small, you can hardly read it.

Is there a straightforward way to make the font bigger?

Bye
Volker

Comprehension question with sftp connection in konqueror

Hi!

I've had ssh installed, and configured it to allow authentification with public keys only. Password authentification is turned off. I've set the SSH port to 3322.

It all worked fine (including sftp in konqueror). It still does, with the exception of sftp in konqueror. I can access my laptop from my desktop machine via ssh, scp and sftp, and vice versa.

Kontact bug (?): Can't synchronize with CardDAV ressource

Hi

I've edited a contact in the addressbook, but I can't get the changes synchronized with my Nextcloud server (via CardDAV).

When I click on "Update addressbook folder" in the menu in the "Contacts" section of Kontact, then I get this message:

Before syncing folder "Kontakte" it is necessary to have the resource online. Do you want to make it online?

I click on Yes, but then the dialog closes and nothing happens. Next time, the same question comes again. The changes don't make it to the CardDAV server, what can be seen in its web interface.

Any ideas?

Volker

Brieftasche kaputt

Hallo!

Ich weiß nicht, was passiert ist, doch plötzlich ist der KWallet-Dienst nicht
mehr verfügbar. Wenn ich mich in Plasma einloggen, bekomme ich Fenster, die
Paßwörter abfragen. Und zwar eins für KMail und eins für den
Nextcloud-desktop-client.

Kwallet broken

Hi

I don't know, what has happened, but suddenly Kwallet is no longer available.
When I log in to plasma on my desktop, I get two windows, each asking me to
enter a password - one for KMail and one for the Nextcloud-desktop-client.
(I'm writing this on my laptop.)

There is this error message: "Couldn't open wallet:
org.freedesktop.DBus.Error.NoReply; Message recipient disconnected
disconnected from message bus without replying"

When I open the KWalletManager, the wallet is empty.

What happened, and how to fix this?

Bye
Volker

Kwallet broken

Hi

I don't know, what has happened, but suddenly Kwallet is no longer available.
When I log in to plasma on my desktop, I get two windows, each asking me to
enter a password - one for KMail and one for the Nextcloud-desktop-client.
(I'm writing this on my laptop.)

There is this error message: "Couldn't open wallet:
org.freedesktop.DBus.Error.NoReply; Message recipient disconnected
disconnected from message bus without replying"

When I open the KWalletManager, the wallet is empty.

What happened, and how to fix this?

Bye
Volker

Grub error: "will not proceed with blocklists."

Hello

I'm afraid I have broken something. grub-install outputs this message:

desktop ~ % LANG=C grub-install /dev/sda
Installing for i386-pc platform.
grub-install: warning: this GPT partition label contains no BIOS Boot Partition; embedding won't be possible.
grub-install: warning: Embedding is not possible. GRUB can only be installed in this setup by using blocklists.

How to recover with a full backup?

Hi!

I'm making preparations for the case when I can no longer boot my machine, and I'm not able to recover with the GRUB recovery mode.

I have a full backup, which includes the system as well as personal data.

When I can't recover, I would install the system anew, from the Kubuntu installation ISO. Then I would unpack my backup, in some directory /backup. Now, how to get a running system again, from that? Could I just replace the top level directories with ones from the backup? Such as:

cd /
mv /bin bin.tmp
bin.tmp/mv backup/bin bin
rm -r bin.tmp

Now, how to make it bootable?

LVM: How to access a foreign volume group

Hi!

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

Hi!

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="http://ppa.launchpad.net/kubuntu-ppa/backports/ubuntu" title="http://ppa.launchpad.net/kubuntu-ppa/backports/ubuntu">http://ppa.launchpad.net/kubuntu-ppa/backports/ubuntu</a> artful main

and

# deb <a href="http://ppa.launchpad.net/kubuntu-ppa/ppa/ubuntu" title="http://ppa.launchpad.net/kubuntu-ppa/ppa/ubuntu">http://ppa.launchpad.net/kubuntu-ppa/ppa/ubuntu</a> artful main

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

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

Hi!

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

Hi

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
contradictions.

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

Bye
Volker

Internet is dying - or is it..?

Hi!

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 193.99.144.80".

slow ubuntu-users list

Hi

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,
Volker

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
resolvconf(8)
# DO NOT EDIT THIS FILE BY HAND -- YOUR CHANGES WILL BE OVERWRITTEN
nameserver 127.0.1.1
search 8.8.8.8
#search fritz.box

This should be enough for trying it. If it works, I'll need to place
that 8.8.8.8 (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 192.168.122.1
traceroute to 192.168.122.1 (192.168.122.1), 30 hops max, 60 byte
packets
1 192.168.122.1 (192.168.122.1) 0.068 ms 0.025 ms 0.025 ms

desktop ~ $ traceroute 192.168.178.20
traceroute to 192.168.178.20 (192.168.178.20), 30 hops max, 60 byte
packets
1 desktop.fritz.box (192.168.178.20) 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 192.168.122.1 address
could be. It isn't listed in my router's web interface.

Internet is dying - diagnostics

Hi

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

1.

Inte

Internet is dying

Hi

The output of ifconfig:

enp2s0 Link encap:Ethernet Hardware Adresse 60:a4:4c:4e:17:47
inet Adresse:192.168.178.20 Bcast:192.168.178.255
Maske:255.255.255.0
inet6-Adresse: fe80::967a:55d6:22b8:8659/64
Gültigkeitsbereich:Verbindung
UP BROADCAST RUNNING MULTICAST MTU:1500 Metrik:1
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

Hello

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)

Hi!

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

Hi!

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?

Bye
Volker

GRUB question

Hi!

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="https://www.thomas-krenn.com/de/wiki/LVM_Caching_mit_SSDs_einrichten" title="https://www.thomas-krenn.com/de/wiki/LVM_Caching_mit_SSDs_einrichten">https://www.thomas-krenn.com/de/wiki/LVM_Caching_mit_SSDs_einrichten</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

Hi!

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?

Cheers
Volker

Two ubuntu bugs

Hi

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)

Hi!

I'm trying to install Nextcloud. I'm following the instructions in the
Nextcloud 12 Server Administration Manual, Installation on Linux:
<a href="https://docs.nextcloud.com/server/12/admin_manual/installation/" title="https://docs.nextcloud.com/server/12/admin_manual/installation/">https://docs.nextcloud.com/server/12/admin_manual/installation/</a>
source_installation.html#installation-on-linux

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

(OT) Google: "Somebody knows your password"

Hi

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.