dmarkey.com

This is the easy way to give virtual machines access to an external network using iptables.

Warning this is very open and probably shouldnt be used in a production environment.

echo 1 > /proc/sys/net/ipv4/ip_forward

iptables -t nat -A POSTROUTING -j MASQUERADE

Just testing QTM, Now using charm

I’ve created a python ctypes-based module for interfacing with samba libwbclient, using ctypes means that it doesn’t require compilation, but this does rely on the ABI be compatible between versions of libwbclient, if you notice strange behavior or random segfaults, contact me.

Its tested on Linux but should in theory work on solaris, or any OS with python ctypes and samba 3.2.

Overview of the class:

class WBClient(__builtin__.object)

Class that interfaces with libwbclient via ctypes.

Optionally pass in a domain name, if no domain name is supplied the

default domain is used(from libwbclient).

Methods defined here:

__init__(self, default_domain=None)

authenticate_user(self, username, password, domain=None)

Authenticates a user

If the winbind seperator is in the username False is returned

This means username\password doesnt work, one must explicitly give

the domain as the 3rd argument if not authenticating off the default domain

Returns the full username in the form of Domain\Username (or a different winbind separator) if successful, None if not.

change_user_password(self, username, oldpw, newpw)

Change user password, (Working with samba 3.4)

get_display_name(self, username, domain=None)

Gets the display name of a user/group

get_group_membership(self, username, domain=None)

This function looks up the group membership of a user,

Returns a list if successful, None if not

get_sid(self, name, domain=None)

Get the SID string of a user/group/machine

list_groups(self, domain=None)

Lists the groups in a domain

list_users(self, domain=None)

Lists the users in a domain

lookup_domain_controller(self, domain=None)

Lookup domain controller for a domain(Could not get to work)

reload_interface(self)

(re)loads Interface details, winbind separator etc

resolve_wins_by_ip(self, ip)

Resolve an IP to a Netbios name

resolve_wins_by_name(self, name)

Resolve a Netbios name to an IP.

Get your copy from http://dmarkey.com/svn/winbind

I upgraded my opensuse 11 installation on my laptop (Dell XPS 1330) to opensuse 11.1 and I notices straight away that my 2d graphics performance was _abysmal_.

The gfx card on my laptop is Intel Corporation Mobile GM965/GL960 using the xorg intel driver.

Things like scrolling in gmail and scrolling man pages in konsole and 2d screen savers all went to a crawl and the driver kept on crashing the machine, I tried to tweak different things in xorg.conf but nothing helped.

I put up with it for a few weeks but today I got fed up and reverted to 11.0, now the performance is back to acceptible levels.

Because of this i’ve been disappointed with the 11.1 release. Luckily from a Kde 3.5 point of view there is little difference between 11.0 ans 11.1.

Hopefully this issue will be solved and a patch released. Actually come to think of it I really should raise a bug.

If anyone else has experienced issues with the intel driver on OpenSuse 11.1 or xorg 7.4 please leave a comment describing your problems.

I’ve hacked the ubuntu intrepid(amd64 only) initrd so you can run the installer in a Xen DomU. No more debootstrap!

The only glitch is that the installer thinks that the xen block devices are part of a SATA array, when asked to activate the array select no.

vmlinuz

initrd

Example config:

memory = 500
name = “intrepid”
vcpus = 1
disk = ['phy:/dev/xenvg/ubuntu-test,xvda,w']
kernel = “/xen/vmlinuz”
ramdisk = “/xen/initrd”
#bootloader=”/usr/bin/pygrub”
vif  = [ 'bridge=eth0']
#this is for your framebuffer if needed
#vfb         = ['type=vnc,vncunused=1,vncdisplay=0,vnclisten=0.0.0.0,vncpasswd=password']

When the install is finished uncomment pygrub and comment out kernel and ramdisk and it should be fully functional. If you have any issues or comments please feel free.

I made this script for bootstrapping and “Xenifying” an ubuntu easily. You will have a working ubuntu domU in 30 seconds flat with a fast mirror.

Root password will always be set to ‘password’. Hostname will be ubuntu , loopback interface will be set up. The sole argument is either a filename or a block device to install the distribution onto. See the top of the script for more configurable options. Notibly the mirror option.

The only prerequisite is that you have (a recent)debootstrap installed. Its available for nearly every distro these days.

Remember that i think you will need Xen 3.3 to boot an ubuntu intrepid DomU.

mkubuntu

How to create an ubuntu server DomU using the normal ubuntu install procedure(64 bit only, 32 bit maybe soon.). It may work or it may not, no guarantees. It did for me.

First download the kernel and the initrd and the ubuntu-8.04.1-server-amd64.iso file from ubuntu.com .

Create the xen config file similar to this one paying attention to all the paths.

Xen Config File:

memory = 256
name = “ubuntutemp”
disk = ['phy:/dev/filevg/ubuntutemp,hda,w','file:/mnt/filelv/Downloads/ISOs/ubuntu-8.04.1-server-amd64.iso,sda:cdrom,r']
kernel = ‘/xen/ubuntutemp/kernel-xen’
ramdisk = ‘/xen/ubuntutemp/initrd-xen’
#bootloader=”/usr/bin/pygrub”
vif  = [ '' ]

Fire up the DomU

xm create -c ubuntu.cfg

Setting up the locale settings will be 1st thing.

Then you will be asked:

Load CD-ROM drivers from a driver floppy? say no
Manually select a CD-ROM module and device? say yes
Select “none”
enter /dev/sda
continue without kernel modules.
Ignore “Could not get identity of device” errors, you will get a few, otherwise continue with the setup normally.

Make sure you have a valid internet connection configured because this will be needed later on in the process

Continue the setup until you get the installation complete dialog that says this:

┌│                         Installation complete                         │
││ Installation is complete, so it is time to boot into your new system. │
││ Make sure to remove the installation media (CD-ROM, floppies), so     │
││ that you boot into the new system rather than restarting the          │
││ installation.                                                         │
││                                                                       │
└│     <Go Back>                                          <Continue>     │

DO NOT select continue. Select go back.

and from the next dialog select “execute a shell” and select continue.

Then issue the following commands to “xenify” the setup.

chroot /target /bin/bash
aptitude install -y linux-image-xen ##this is where you need your internet connection
sed -ibak ’s/generic/xen/g’ /boot/grub/menu.lst
sed -ibak ’s/splash/console=xvc0/g’ /boot/grub/menu.lst
mv /etc/event.d/tty1 /etc/event.d/xvc0
rm /etc/event.d/tty*
sed -i ’s/tty1/xvc0/g’ /etc/event.d/xvc0
sync
exit
poweroff

Probably best to do these 1 by 1, its important every single command finishes.

Now we need to edit the configuration file to this:

memory = 256
name = “ubuntutemp”
disk = ['phy:/dev/filevg/ubuntutemp,hda,w','file:/mnt/filelv/Downloads/ISOs/ubuntu-8.04.1-server-amd64.iso,sda:cdrom,r']
#kernel = ‘/xen/ubuntutemp/kernel-xen’
#ramdisk = ‘/xen/ubuntutemp/initrd-xen’
bootloader=”/usr/bin/pygrub”
vif  = [ '' ]

Obviously changing paths as needed.

And then fire up the machine again

xm create -c ubuntu.cfg

After a short while you should be presented with a lovely login dialog:

Ubuntu 8.04.1 ubuntu xvc0

ubuntu login:

And thats it, you have a fully functioning ubuntu DomU using the starndard ubuntu server setup procedure. FYI LVM setups have been tested and worked too, Encrypted LVM hasnt been tested.

So I wanted to install an ubuntu DomU in my Centos5 Dom0 which proved to be quite the task due to the lack of debootstrap. So an idea was to get the ubuntu install initrd and modify it so it would work with Xen so the installer would work like it would in a normal system. I succeded to an extent, with a few minor operations at the end of the install its reletively simple to install ubuntu using this system.

I’ll post my intructions and kernel/initrd later.

So I took on to put (open)Solaris in a Suse Linux 10.3 Dom0 with xen 3.1 64bit. I made a LOT of silly mistakes along the way, the first and most time wasting mistake was trying to work off the first CD instead of the DVD. The reason this was such a waste of time is because the CD doesn’t come with the 64 bit miniroot(boot_archive) so the kernel cant be loaded properly(look out for panic[cpu0]/thread=d30cfe00: HYPERVISOR_mmu_update() failed) , this wouldnt have been a problem if I was using 32 bit but unfortunately I wasn’t.

The general procedure after you download the DVD is as follows. As I’m using suse they like to bastardise things so it doesn’t come with pygrub, which is needed for a simpler install, so i had to fetch the kernel and the boot archive myself by mounting the ISO loop back and fetching the following files:

mount -o loop /home/dmarkey/sol.iso /mnt
mkdir /xen/solaris

cp /mnt/boot/amd64/x86.miniroot /xen/solaris

cp /mnt//platform/i86xpv/kernel/amd64/unix /xen/solaris

OK so now me have our kernel and our boot archive, now to generate our XEN configuration file.

name = ’solaris’
memory = ‘1024′
disk = [ 'file:/home/dmarkey/sol.iso,6:cdrom,r','file:/home/dmarkey/solaris.disk,0,w' ]
vif = [ 'mac=00:16:3e:00:20:11' ]
on_shutdown = ‘destroy’
on_reboot = ‘restart’
on_crash = ‘destroy’
#root=’/dev/dsk/c0d0s0′
kernel = ‘/xen/solaris/unix’
ramdisk = ‘/xen/solaris/x86.miniroot’
extra = ‘/platform/i86xpv/kernel/amd64/unix -B install_media=cdrom’

Because the boot archive is so bloated, you need a LOT of ram to get it booted, thats why I’m allocating 1024 meg of RAM. So now we have to generate the hard disk file, use something like DD to create a >8G file in /home/dmarkey/solaris.disk or wherever you want to put it, remember to change all the file paths in you configuration. I named this configuration file /xen/solaris/solaris.

So now we should be able to boot, so we do:

xm create -c /xen/solaris/solaris

And fingers crossed we should be able to perform a Solaris setup. When the setup is finished we need to edit the config file. First uncomment the #root=’/dev/dsk/c0d0s0′ line, and then we change the extra line to simply extra = ‘/platform/i86xpv/kernel/amd64/unix’ and you can reduce the amount of ram to 512 if you want.

The performance of Solaris under XEN is i would say near to native. The only problem is that solaris need 512mb of ram to even attempt to boot. This is because of the huge boot_archive (x86.miniroot). In another entry I will go through the steps to make a smaller boot_archive and now my Solaris under Xen will successfully boot with 96M of ram!

So the resize of /home worked but i couldn’t manage to resize the block device size. So fortunately i had a spare 200gb hard disk, so i made a new volume group and added the new hard disc as a physical volume, i then made two logical volumes on that, one for root and one for home and format them both with reiserfs, the root logical volume i mount on /mnt/tmp and copy the root filesystem with cp -vaRx / /mnt/tmp which seems to work properly, and then the same for root.

My next problem is I cant boot off the lvm because the required kernel modules arent in initrd. so I have to run mkinitrd /dev/system/rootlv from the path of the root file system device it works out what modules are required to allow the kernel to mount the root filesystem. Then /boot/grub/menu.lst has to be updated and /etc/fstab to mount the logical volumes instead of the old physical ones.

Cross your fingers and do an init 6, and hopefully you will have a bootable system off the logical volume.

If your in luck you can now start working on moving the volume group back onto the original hard disks, or in my case the dmraid. I’ll update with that later.