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Ubuntu keeps sending DNS queries to daisy

12 December 2014 Leave a comment

Recently I noticed that my Linux desktop (Ubuntu 14.04.1 LTS)  sends a DNS query to daisy.ubuntu.com about every 8 seconds. I do not want that, so I did some googling. Turns out that it is a known issue for more than 2 years.

What is happening

A service called whoopsie is actively doing those repeated queries to check if your system is on-line. A misconfiguration in the combination of network manager and dnsmask makes the query to always go to the internet instead of caching the query result for some time. There are several workarounds that stop this, see e.g. https://bugs.launchpad.net/whoopsie/+bug/991481/comments/19

On my desktop computer, I have statically configured my network, so it is not that useful to have the network manager active. I decided to permanently stop this service.

sudo -s
initctl stop network-manager
echo 'manual' > /etc/init/network-manager.override

That should make the query seems less often, it should prevent disabling caching. Unfortunately I see the queries as much as before. So, even as I do see some usefulness in reporting errors, the error reporting should only go on-line after I allow it to go on-line, and not every few seconds, so whoopsie has to go..

Removing whoopsie

The solution to this constant DNS traffic is to switch-off whoopsie. I decided that uninstalling it was the easiest way, and you can undo it by installing it again. So uninstall it, like this:

sudo dpkg --remove whoopsie

After that, no DNS queries to daisy.ubuntu.com anymore!

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Categories: Linux Tags: , ,

webserver experimenten

7 July 2013 Leave a comment

Aangemoedigd door een serie blogs op ArsTechnica en ook omdat er hier eens nginx werd gebruikt en niet apache, heb ik op mijn thuis linux web browse machine de stappen gevolgd om deze tools te bouwen.

De PPA repository voor nginx in het artikel geeft een oudere versie uit de 1.5.x reeks. Intussen is er ook een officiele repository op de nginx site zelf. Ook voor mariaDB is de repository link intussen veranderd.

Ik heb hierbij het certificaat deel met het aanvragen van een echt trusted certificaat overgeslagen en een Self Signed Certificate gebruikt volgens deze instructie, maar ook hier iets, met het idee om later toch nog eens een ‘echt’ certificaat te regelen dat wel door iedereen ‘trusted’  is.

De genoemde instructies waren niet duidelijk m.b.t. welke file nu wat precies bevat en die dan waar gebruikt moet worden in de nginx configuratie. Na wat proberen en testen wel werkend gekregen. Is goed voor een latere blogpost. Het netjes configureren van IPv6 in nginx was een uitdaging, maar uiteindelijk niet moeilijk (als je de oplossing weet). Belangrijk is dat je in de listen regel alleen een poortnummer opgeeft en , maar geen dns-naam. De dns naam (als je z.g. hostheaders gebruikt en meerdere ‘vhosts’) komt in de server_name regel. De betreffende stukjes configuratie zien er nu zo uit:

server {
#listen 80 default_server; #deze staat standaard aan
listen [::]:80 default_server ipv6only=on;
server_name _www.roheve.nl;
….
}
server {
listen 0.0.0.0:443 ssl;
listen [::]:443 ssl ipv6only=on;
server_name _www.roheve.nl;
….
}

In dit blog nog wat uitleg over bijzonderheden over ipv4 en ipv6 onder linux (iets met hybrid en separate)

M.i. een aanrader om de serie installatie-stappen eens te doen op zo’n regenachtige vakantie dag. De echte aanleiding was echter dat (de voeding) van m’n Acer H324 homeserver het een tijdje terug begeven had en ik daarop ook een miniwebsite had draaien en ik wilde dat speeltje herstellen.

Categories: Linux, Things Tags: , ,

Linux Samba with CIFS and Windows Home Server

7 October 2012 Leave a comment

Last year I experimented with a borrowed NAS  and wanted to use it as a backup for my windows home server. At home most of my computers run linux and I wanted to map those shares automatic on my main desktop. Not wanting to re-invent a wheel again, I did a google search and found this:

http://www.digiplace.nl/2011/01/27/hoe-verbind-je-ubuntu-automatisch-met-een-samba-share-op-een-qnap-nas/

So I needed to put the following lines in  /etc/fstab, or for testing, something similar after the sudo mount command

my Nas (all on the same line):
//nas/data /media/nas cifs credentials=/root/.naslogin, rw,iocharset=utf8,dir_mode=0777,file_mode=0777 0 0

My Homeserver (all on the same line):
//whs/ebooks /media/whs/ebooks cifs credentials=/root/.whslogin, rw,iocharset=utf8,dir_mode=0777,file_mode=0777 0 0

This worked for my NAS but not for my windows home server.  Mounting the share from the home server  failed . It just trow an error: “mount error(5): Input/output error“, that pointed to the right solution. NOT!

After some searching, I found the reason. I was not using the netbios name for the windows server, but an alias.

http://lists.samba.org/archive/linux-cifs-client/2005-January/000649.html

What happened.

Mounting the share failed because windows refused the connection. The internal netbios name of my home server did not match the name in the mount command.

Remember that for windows, the computer name is also the netbios name, and the home server is running Windows Home Server (i.e. Windows 2003). I decided to have a dns name for my home server different than the internal computer name, so there was a mismatch.

Once I knew the cause, the solution to this was easy. Just use the same computer name as the computer thinks it has, and not something else 🙂 even through that other name resolves to the same computer. After adding the netbios name of my home server to the hosts file on linux and using the netbios name in the mount command, it worked.

sudo mount -t cifs //roheve/ebooks /media/whs/ebooks -o credentials=/root/.whslogin,iocharset=utf8,dir_mode=0777,file_mode=0777,nounix

And now it ‘just works’.

PS: I need to remember these to (copy_n_paste is easy)

sudo mount -t cifs //sw-hy1.testlab.local/c$/data /media/testlab/hy1 -o credentials=/root/.testlab,iocharset=utf8,dir_mode=0777,file_mode=0777,nounix

sudo mount -t cifs //sw-hy2.testlab.local/data /media/testlab/hy2 -o credentials=/root/.testlab,iocharset=utf8,dir_mode=0777,file_mode=0777,nounix

Categories: Linux, Windows Tags: , , ,

Dual boot Windows7 and Ubuntu on my Netbook

17 July 2011 Leave a comment

Added Linux to my Netbook that came with Windows pre-installed.

As I use mostly Linux at home, but occasionaly need Windows (e.g my plugwise gadgets came with a windows only software). As I do not want to install ‘home’ software on my Windows 7  ‘work’  laptop, I decided to keep this Windows on a small partition, as I paid for it’s license anyway, and could be usefull.

This Windows 7 is a ‘starter edition’, i.e. cheap, but did not encounter a real limitation. Well I can not ‘RDP’  into it, but that is also not possible with the Windows 7 home versions.

Well, next step was to get Ubuntu Linux on it (I use that version on my ‘main’ home desktop computer). To not re-invent the wheel while making it dual-boot, I looked for and found a nice tutorial for this. Must say it works well that way.

The basic steps involved are:

  • Shrink the windows partition to a workable minimum to make room for the linux partitions.
  • Install EasyBCD in windows to configure the windows bootmanager
  • Install ubuntu, make sure to put ‘grub’ in the linux bootpartition, not the disk bootsector
  • Add ubuntu to the windows bootmanager (and make it the default)

Job done…

I made this entry, so I can find the tutorial again, just in case I need it.

 

PS.

A restriction in Excel 2010 Starter I bumbed into was that there is no option to connect to an SQL or Access database. Well this is ‘advanced’  usage, so logical it is missing.

Categories: Linux, Windows