Postings by Dave Stevens

OT? hardware recommendation?

I'd like to connect an ethernet 10GB port to en external usb3 hub and
can't see a bit on ebay to do this, anyone have a pointer?

Overall I have only a rj-45 socket for i/o to an external HD with a
usb3 connection, that's the issue I want to address. Seems as if it
should be cheap and easy but I can't seem to find one.



OT - driver maintainer details?

In the article below about kernel updates is a reference to a driver for
a Plantower PMS7003 particulate matter sensor. I'm using this series in
air pollution monitoring and its usual interface to the computer
is over a serial line. I consequently am very curious about how and why
it would need a specific kernel module.

Can anyone refer me to more information about the originator of this
patch? I'd rather ask directly but don't know how to go about it.



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can't find asus wifi after wiping W10 for mint

my friend said sure go ahead and wipe windows 10 and install mint just
so you save my files and put them back on. all of that was routine and
worked ok except that the wifi quit. I plugged a little usb wifi radio
in and it was recognized and works fine. I've looked in dmidecode and
in dmesg for hints.

OT: pingdom workalike?

I've been using pingdom for some years to get outage alerts. It gave
lots of false positives but seemed better than nothing. They're
monetizing the previously free service and I'm curious if people have a
recommendation about a similar program.


This is done by ensuring that the web server can write to these locations.

I want to set up a folder so that I can use a plugin in wordpress, the
instructions work up to the point where I get this direction, but I
don't know how to ensure that the apache instance has write access to
the folder. I have admin rights. Suggestions? Reference?



OT: reference to a wordpress resource??

I've got a ubuntu server and wordpress site. I want to upload hundreds
of files to the WP media library and have them found by interested
users using the built in WP search function. Can anyone refer me to a
reference for this? I've gone through the WP plugins and have not found
what I want. Also a WP mailing list as opposed to forum would be useful.



how much space are my .isos taking up?

I was surprised when I ran "locate .iso" to see twenty or so in the
list. Does anyone know a handy way to get a listing with file sizes?



who maintains mailman 2.1 for ubuntu 18.04.1?

I installed webmin-virtualmin-mailman and mailman in that order. I
have a problem with the installation and asked on the mailman list and
was referred to the maintainer of the distribution's version. I don't
know a) who that is or b) how to find out (apart from asking here).



evolution error on first start

I've installed evolution and on first running it, from a terminal, I

(evolution:3870): e-data-server-WARNING **: e_module_load_all_in_directory: Error opening directory '/usr/lib/evolution-data-server/credential-modules': No such file or directory

I've looked in /usr/lib/evolution-data-server/ and sure enough there
isn't a file or directory called credential-modules. I'm not surprised
in a way because I haven't provided any credentials. My understanding
is that a first run wizard will start up to solicit such information
but this has not happened. Ideas?


help with serial i/o from a device?

I've got a Plantower PMS5003 particle counter that reports
over a serial (RS-232) cable. Inline to my USB port is a uart, acting
as a level shifter. Node.js has a module that allows me to read
successfully from the device (or, strictly speaking, from the USB port).
It is, however, a bit large and clumsy, a lot of overhead to just copy
serial data (at a low rate, about 200 bits per second, into a file.

cron issue

I've set up a cron job to run logwatch at night.

Output from command /usr/sbin/logwatch --mailto=....


/var/cache/logwatch No such file or directory at /usr/sbin/logwatch
line 634.

and line 634 is:

opendir(TMPDIR, $Config{'tmpdir'}) or die "$Config{'tmpdir'} $!";

I don't understand what file is missing. I can confirm
that /var/cache/logwatch doesn't exist. Should I just arbitrarily make
one? Is it an install error? I've just installed the system, U18.04, up
to date.

Ideas welcome.



I've got an Acer laptop that came with Windows 10 installed and I'd
like to make it dual boot with Ubuntu, don't much care what version.
I've prepared a bootable usb stick. It boots fine with other computers
but not on the Acer. I've disabled secure boot in the BIOS and have no
option to change the boot order, Windows Boot Manager is the only

Can anyone point me to an information source for this issue? Off-list
is fine.



module issue?

I want to configure nat and I get this:

sudo iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE -v
iptables v1.6.0: can't initialize iptables table `nat': Table does not
exist (do you need to insmod?) Perhaps iptables or your kernel needs to
be upgraded.

uname -r


ls -l /lib/modules
total 8
drwxr-xr-x 3 root root 4096 May 24 03:32 4.14.34+
drwxr-xr-x 3 root root 4096 May 24 03:32 4.14.34-v7+

I think I understand that /lib/modules will need to have an entry for
4.9.80+ but doesn't.
I've run sudo apt upgrade so I don't think that's a problem .But I
don't see how to proceed.

OT?: break up an incoming data stream into fixed length lines? in bash?

I'm using U16.04 to read data from a sensor. The incoming serial data
stream has no newlines, just continuous bytes. In the datastream the
letters B and M occur together at the start of every 24 byte
subsequence. I'm reading the data using getserial with appropriate
speed and parity parms. I don't see a simple way to break it up into
lines with each line having 24 bytes. Does anyone care to suggest a
method? I'd use a bash function if there is one.



firefox quantum saved logins export import??

I'm changing laptops and need to export saved logins (several hundred)
from the old one to the new one, both firefox 58. I can't find an
add-on to do this and it seems (although this is not really clear) that
there isn't one. Anyone have experience (especially successful) with


export wifi logins?

I'm switching laptops and would like to have a simple way to export or
otherwise copy my wifi logins to the new computer, anyone know a way?


secondary screen only works until login


I'm using 16.04 on a Toshiba laptop. I want to use a secondary display,
a Samsung SyncMaster 712n. I have it connected to the Toshiba's
external VGA port. The display powered up and showed system activity
right up until the automatic user login took place. I had the system
configured to log me in without asking for a password. When the login
took place the secondary display went blank. The system control panel
shows an unknown secondary display.

In an attempt to see where the problem lies I made a new (second) user
with a password and required a credential check at login.

root only on newly initialized sata drive?

I have booted a live 16.04 and used gparted to remove the partition
then recreate it and format it to ext4. Fine so far. When trying to
save to the the drive I can't unless I use sudo. The permissions show
the drive's only partition is owned by root. How do I change this? I
know how to chown but don't see why it's created as root-owned by


lossless compression of still images - recommendations?

I'm making a long series of exposures of a landscape where there will be
only very small (but potentially significant) changes from frame to

OT: nextcloud for ubuntu?

I'm curious to try nextcloud, which describes itself as an owncloud
fork. They don't have a ubuntu desktop client on their site. Does
anyone know of plans to include a desktop client in the ubuntu repos?


cp only files without errors

I recently had to copy an NTFS volume from a dead Windows laptop. I
mounted it and copied (using cp) about 250K files to an external
volume. There were several files for which errors were present and for
each I had to answer "skip" at a prompt. I would much rather specify
something like "skip on error" just once at the beginning but don't
see how. Anyone?


"Error splicing file: File too large"

I made a zip file of 14.1 GB and copied it to a new 16GB usb flash
drive and got this message at about the 99% mark. I didn't know there
was a file size limit and the drive properties showed enough space

Does anyone have a suggestion where I can look for more information
(and a solution?)

2GB RAM, lots of space on /dev/sda1, /dev/sdb1 (the flash drive) is
FAT32, is that an issue?


make a time lapse movie using gpu and 14.04?

I expect to have a lot of still frames and would like to make a movie
from a specified sequence reasonably quickly. I'm currently using
ffmpeg which works fine and is flexible but fairly slow. Does anyone
know of a method that could use the GPU to speed up the process? 14.04.
I haven't yet set up the final system so I could get any card in
principle if there's one that's preferred.


Convert page to original flat html page?

So the server backups were unusable, but has a good copy
of the flat html (non-do) page. I can save and edit the page to
restore the original, but does anyone know of a better routine or
facility for doing this? It must happen a lot. Using 14.04.3


little radio driver needed

I was given a teeny usb radio for wifi but no docs or drivers, want to
use it with ubuntu. I think it works, the donor says it is unused.

stop postfix on U14.04?

I want to stop postfix on my U14.04 system. I can "sudo service
postfix stop" and that works fine. But a problem is that AC power is
flaky. I'm working on that separately but in the meantime postfix
restarts when power cycles. I've looked for and found ways to remove
postfix but that's overkill - all I want is to prevent it from running
even through power cycles until explicitly restarted.

Can anyone refer me to a man page or tutorial on that?



wifi driver query

In reading about kernel 4.3 I see that the driver for the Realtek
8192e wifi radio is to be updated. I have one of these now using
kernel 3.16.0 as part of U14.04. Where can I ask if the updated driver
will be present in 16.04? I've been thinking of updating to that in
the Spring when it becomes available. I don't understand where I can
find out. Anyone?


kernel errors I don't understand

Running logwatch give this message in part, I don't understand its

EXT4-fs (sda1): re-mounted. Opts:
usrquota,grpquota,errors=remount-ro ...: 2 Time(s)


backlight utility?

I've got a samsung n220 netbook into which I recently installed a ssd.
I took advantage of the install to do a clean fresh install of U14.04.
It went well except that I can no longer adjust my backlight. The
function keys that used to do this appear to work - I get a little
slider display on-screen - but there isn't any actual difference in
screen brightness. Anyone have an idea about this one? I tried the
software centre under acpi and backlight but the hits don't seem


desktop config questions - U14.04

I have a laptop with U14.04.2 and am using Gnome Flashback (Metacity)
desktop and have several knowledge gaps.

On the top of the screen is a panel showing on the left the Apps and
Places menu headers, then various program icons as single click launchers
and on the right a wifi and language icon and then the bluetooth,
battery charge and so on icons.

Somehow (accidentally) I've got a document icon on the top panel. It
points to a file that has now been erased from the usb key that it
points to, which is itself absent.