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Connection for controluser as defined in your configuration

Symptom: After upgrade to Ubuntu 9.04 (Jaunty) phpmyadmin continues to work fine but shows the following error on several pages:

"Connection for controluser as defined in your configuration failed."

Software Versions:

Ubuntu Jaunty 9.04
Phymyadmin : 3.1.2deb1

Reason: The advanced features available in phpmyadmin require the installation of a database to support them and the phpmyadmin control user should have rights to modify the data in the phpmyadmindatabase

Firstly create the database for advanced features using
cd /usr/share/doc/phpmyadmin/examples/
sudo gunzip create_tables.sql.gz
mysql -u root -p < create_tables_mysql.sql

Check the values of contents of the following variables
$dbuser='phpmyadmin';
$dbpass='xxxxxxx';

in the file /etc/phpmyadmin/config-db.php

You can do this with something like:

sudo nano -w /etc/phpmyadmin/config-db.php

Finally, Log in to phpmyadmin and create create a username phpmyadmin that can connect from localhost then add add at least SELECT, INSERT, UPDATE, DELETE privelages to the newly created phpmyadmindb for the user phpmyadmin using the password identified from /etc/phpmyadmin/config-db.php

References

Posted By: admin on May 28, 2009 11:58AM Category:Ubuntu Add Comment

Remote Internet Access to Ubuntu Intrepid and Jaunty workstation

Placeholder for article which talks about using Hamachi and NX to access Ubuntu workstations over the internet.

It will usually work even when you dont have a network routable ip address and through firewalls.

There are clients for both Linux and Windows fro both NX and Hamachi, so you can control your server from either

Posted By: Admin on May 06, 2009 10:02AM Category:Ubuntu Add Comment

Swine fever and internet domain registrations

Well I just thought I would make a check of whois records for terms related to the recent outbreak of swine fever sometimes know as novel flu and more officially classed by the WHO as Influenza A H1/N1

Google insights for search shows that key search terms people are using for the current outbreak are (not necessarily in the right order)

swine flu
the swine flu
swine flu symptoms
influenza porcina
gripe porcina
mexican flu
mexican swine flu
tamiflu
flu symptoms

Looking at the domain registrations you can see

Domain Registered on:

swineflu.com 2000-03-07
theswineflu.com 2009-04-24
swineflusymptoms.com 2007-05-13
influenzaporcina.com 24-Apr-09
gripeporcina.com 24-Apr-09
mexicanflu.com 2009-04-23
mexicanswineflu.com 24-Apr-2009
tamiflu.com 28 Jun 1999
flusymptoms.com 20-mar-2002

Interesting!

Posted By: Admin on May 05, 2009 02:05PM Add Comment

Running Xen on Ubuntu Intrepid and Jaunty [12]

Step by Step guide to using Xen with Ubuntu Intrepid and Juanty - How to Set Up Xen Dom0 on Jaunty Jakalope 9.04

Introduction

Distribution: Ubuntu 9.04 (Jaunty Jackalope) 9.04 - Should also work with Ubuntu 8.10 (Intrepid Ibex)

This is tried and tested on a 32bit machine. I cannot use KVM with this machine as virtualization extensions are not supported. While this machine was built before Intel or AMD had introduced their virtualizaion extensions, I notice that even very new machines (such as laptops, netbooks and so on) are being sold with CPUs that don't have these extensions. For this reason alone KVM cannot be the only virtualization solution available on linux. For me, as I already have quite a bit of experience with Xen, Xen continues to be the best option.

Installing a Kernel Dom0 that works

To get started you will need a Debian Dom0 Kernel. There kernel I used is this one: linux-image-2.6.26-2-xen-686_2.6.26-15_i386.deb

Download from here:

Kernel: http://packages.debian.org/lenny/i386/linux-image-2.6.26-2-xen-686/download

Modules: http://packages.debian.org/lenny/i386/linux-modules-2.6.26-2-xen-686/download

Then install using

sudo dpkg -i linux-image-2.6.26-2-xen-686_2.6.26-15lenny2_i386.deb linux-modules-2.6.26-2-xen-686_2.6.26-15lenny2_i386.deb

Install Xen Hypervisor and tools

Obviously, in order to get Xen installed, I installed the latest versions of Xen available in the Xen repository, like as follows:

From the menus choose to System -> Administration -> Software Sources you will see several check boxes.

Canonical-supported Open Source software (main)
Community-maintained Open Source software (universe)
Proprietary drivers for devices (restricted)
Software restricted by copyright or legal issues (multiverse)

you should checked all these 4 boxes then click 'Close'. You should see a box that says "The information about available software is out of date". Click on the reload button. When these boxes have gone you should be able to use:

sudo apt-get install python2.5 ubuntu-xen-desktop

Configuring the bootloader

I use grub as my bootloader, so the entry in menu.lst to load and run Xen looks like this:

    title        Xen 3.3 / Ubuntu 9.04, kernel 2.6.26-2-xen-686
    uuid        bd2c08f6-e705-4c85-8fdb-aa884ca8a0b7
    kernel        /xen-3.3.gz
    module        /vmlinuz-2.6.26-2-xen-686 root=UUID=c397979f-01e0-4180-83eb-8c9324fced1e ro console=tty0
    module        /initrd.img-2.6.26-2-xen-686
    quiet

If you are lucky, when you install the kernel and modules using dpkg -i, the utility grub-update should automatically create the right menu entry. root= should be pointing to the correct file system.

Getting Dom0 networking running

The key to getting the network running is removing the Ubuntu network manager

    sudo apt-get remove network-manager

then update the file /etc/network/interfaces to look like this:

    auto lo
    iface lo inet loopback
 

    auto eth0
    iface eth0 inet dhcp

This should work fine for most people who have DHCP server running which is common in both a corporate environment and an environment where you have an ADSL router running.

Configuring and Installing DomU clients

Creating New DomU Clients

If you would like to run Jaunty DomU clients on your Ubuntu Dom0 machine, I have written another article on how to create DomU images using the Xen tool xen-create-image. This tool provides a largely automated way of creating the disk images and the configuration files required to run Jaunty DomU images. You can read the article here: http://www.infohit.net/blog/post/installing-and-running-xen-domu-jaunty-on-dom0-ubuntu-juanty.html

Installing Existing DomU images

You can use the Debian kernel installed in the earlier stage as a DomU kernel too, so this means you can create a configuration file something like this:

    kernel      = '/boot/vmlinuz-2.6.26-2-xen-686'
    ramdisk     = '/boot/initrd.img-2.6.26-2-xen-686'
    memory = 1024
    name = "ubuntu"
    vif = [ 'bridge=xenbr0' ]
    dhcp = "dhcp"
    disk = ['file:/workarea/xen/images/ubuntu.img,xvda1,w',
            'file:/workarea/xen/images/swapubuntu.img,xvda2,w']
    root = "/dev/xvda1 ro"

You should note that the virtual console of this kernel is found on /dev/hvc0 therefore if you want to be able to use the xen console (xm create -c domain or xm console domain) you must run a getty on /dev/hvc0 either by updating /etc/inittab or placing an entry in /etc/event.d/

References

Posted By: Admin on May 05, 2009 01:58PM Category:Ubuntu Add Comment | View Comments [12]

Hey there,

I'm about to start a XEN install and trying to choose a Distro.

I've got a buch of Exp. with Gentoo, but have had to port to ubuntu for work recently.

Have you managed to get the Dom0 fully running on jaunty yet?

Many thanks

Posted By: km0ti0n on May 29, 2009 06:07AM

Hi km0ti0n, Yes I have it running on Jaunty in a usable fashion now. My experience is much the same, moved to Ubuntu after about 4 years with Gentoo. I have just significantly updated the article so there should be enough clues to get you going. Otherwise drop a note here. I will continue to update the article in any case to add detail on DomU clients and so on.

Posted By: Admin on May 29, 2009 07:26AM

Hi there.

Thanks to your notes I've been able to get the XEN kernel installed and the dom0 up and running, both using the wireless (wlan0) and using the cable (eth0).

I'm now starting to create my domU machines.

Many thanks.

Andy

I've tri

Posted By: km0ti0n on Jun 08, 2009 04:42AM

Dear Admin,
I have tried the steps according to ur notes, but couldnt able to run it till now. the link you provided for the xen kernel support, now it opens into -17 version rather than -15 as mentioned in ur document.

I am using jaunty and wants to run xen on it. i tried ur steps but it doesnt boot. i checked the menu.lst and its ok.

please help me

Posted By: Iennod on Jul 17, 2009 02:11AM

Why does network-manager need to be uninstalled? Managing wireless on a laptop without is more painful.

Posted By: kurt on Jul 17, 2009 04:05PM

While applying patches as you said above I got an error
patch: ../xen-patches/60002_linux-2.6.19-rc1-kexec-move_segment_code-x86_64.patch1: extra operand

Posted By: Tapas on Nov 14, 2009 08:41AM

I have a static IP address but still it is not working
auto eth0
iface eth0 inet static
address 192.168.1.1
netmask 255.255.255.0
gateway 192.168.1.254
broadcast 192.168.1.255
dns-nameservers 192.168.1.254

My DNS is not in the same subnet and more over it is from an ADSL router in both the cases it is not working

Posted By: Tapas on Nov 14, 2009 01:31PM

ok i forgot to add the entries in /etc/resolv.conf

Posted By: Tapas on Nov 14, 2009 01:41PM

Ok finally it is working thanks a lot for your tutorial I had to restart my machine even after doing /etc/init.d/networking restart did not worked as I expected but then it worked later on

Posted By: Tapas on Nov 14, 2009 01:48PM

who so ever is having the static IP please note that dns-nameservers entry above I had deleted from my file so just google that and then you will be able to use it

Posted By: Tapas on Nov 14, 2009 02:03PM

Getting Dom0 networking running with a Static IP fails. I am getting
SIOCSIFADDR No Such Device
eth0:ERROR while getting interface flags:No Such Device
Following some pointers on other blogs I removed the entries in the /etc/udev/persistent-rules.d/70-percent-net.rules file.
I also tried the eth0 renamed as eth1
I tried adding e1000e module support even then I was getting the same error.
I have 64bit hardware. I tried the above on 32-bit Ubuntu as well as 64 bit.
But that error still remains.
Any idea what is causing that?

Posted By: FreeMind on Jan 08, 2010 07:48AM

Hi,
Nice Article, I am trying to set up private cloud using XEN and EUCALYPTUS. I went through this procedure and every thing was working fine till I use xm or xend command is giving following error:
-----------------------------------------------------------------------

ERROR Internal error: Could not obtain handle on privileged command interface (2 = No such file or directory)
Traceback (most recent call last):
File "/usr/sbin/xm", line 8, in <module>
from xen.xm import main
File "/usr/lib/python2.6/dist-packages/xen/xm/main.py", line 61, in <module>
xc = xen.lowlevel.xc.xc()
xen.lowlevel.xc.Error: (1, 'Internal error', 'Could not obtain handle on privileged command interface (2 = No such file or directory)')

-----------------------------------------------------------------------

I am logged on as a super user in the PAE kernel. Still the handler of the privileged method xc() is missing.
Could you please Help me with this. Its been 4 days since i started installing XEN... Thanx in advance

Posted By: Varun Pandey on Feb 28, 2010 09:30PM

Infohit