fook sheng technical blog

Solaris Core dump analysis

2011-07-22T14:56:00.002+08:00

A Solaris server running Glassfish keep crashing in my company and even the Oracle consultant has no clue, after he analysed the core dump files.

I have no idea on how to tackle the problem either. But it happen again and again and I decided that it is time for me to learn how to analyse core dump files.

Of course Google is my best friend for a task like this, but some knowledge of reverse engineering helps alot here, without of which might mean getting nothing out even when presented with the correct information.

pflags

Run pflags and look for signals that caused a crash. Here I found a SIGSEGV signal.

pflags core.hostname04.703.26100.java > pflags.txt

and I do a grep and found in the file:

/243: flags = DETACH
sigmask = 0xfffffeff,0x0000ffff cursig = SIGSEGV

The crash occured in thread number 243.

pstack

pstack core.hostname04.703.26100.java > pstack.txt

and look for 243. I got :

----------------- lwp# 243 / thread# 243 --------------------
ffffffff7dda9840 jni_GetByteArrayRegion (1111471c8, fffffff80b6155c8, 0, 108, fffffff80b6054f8, 111147000) + f8

The function jni_GetByteArrayRegion is causing the crash. It is located in memory address ffffffff7dda9840.

pmap

pmap core.hostname04.703.26100.java > pmap.txt

portion of the pmap.txt:

....

FFFFFFFF7DB12000         16K r----
FFFFFFFF7DC00000       8192K r-x-- /opt/jdk1.6.0_24/jre/lib/sparcv9/server/libjvm.so
FFFFFFFF7E400000       2048K r-x-- /opt/jdk1.6.0_24/jre/lib/sparcv9/server/libjvm.so

........

So the culprit is /opt/jdk1.6.0_24/jre/lib/sparcv9/server/libjvm.so

I found an easier way to locate the executable that contains the offending function. I will write about it in a later post.

Since the library (/opt/jdk1.6.0_24/jre/lib/sparcv9/server/libjvm.so) is part of the Java Runtime Environment, I have filed a case with Oracle and they are currently investigating. I saved them some work infact :)

Have a nice day :)

fook sheng

Microsoft Windows memory management

2011-06-17T17:34:00.001+08:00

Some notes on Microsoft Windows Memory Management (limited to 32 bit OS)

Maximum memory available is 4G (because Microsoft is dumb enough to ignore segment registers. See http://social.technet.microsoft.com/Forums/en/w7itproperf/thread/9feee84c-44f8-48fa-b49f-9199473e3006)
32 bit applications can access up to 4G of memory but in actual fact it can only access 2 G, which is known as the user mode virtual address space (user space)
User mode address space range from 0000 0000 - 7FFF FFFF
The other 2G of memory is known as kernel mode address space (system space) and it is reserved for the OS
Kernel mode address space range from 8000 0000 - FFFF FFFF
System space contain the global OS code and data structures that are visible to each process

References

http://blogs.technet.com/b/askperf/archive/2007/09/28/memory-management-x86-virtual-address-space.aspx

NFS on MS Windows Server 2003

2011-01-07T14:52:00.000+08:00

I am trying out Zen Cloud and a need for NFS as a shared resource arise. My colleague has a Windows server running and i found out that I can run NFS server on the Windows 2003 server.

http://blog.peacon.co.uk/wiki/Creating_an_NFS_Server_using_Windows_Server_2003

In short you need Services for Unix (SFU), which can be downloaded at:

http://www.microsoft.com/downloads/details.aspx?displaylang=en&FamilyID=896c9688-601b-44f1-81a4-02878ff11778

The version I had is Windows Services for UNIX Version 3.5.

Happy New Year and cheers :)

/libexec/ld-elf.so.1: Shared object "libidn.so.17" not found, required by "skipf ish"

2010-04-15T17:52:00.000+08:00

/libexec/ld-elf.so.1: Shared object "libidn.so.17" not found, required by "skipf
ish"

you got this when u run skipfish...

but

$ ls /usr/local/lib
libidn.a libidn.la libidn.so libidn.so.17 pkgconfig
$

they are there!

by using numerous keywords, and finally using "/usr/lib /usr/local/lib" to google, i found this:

http://ubuntuforums.org/showthread.php?t=289848

Re: /usr/local/lib and /usr/lib

iamnafets,

Unless running `ldconfig` is part of the "make install" command for installing the library, your system doesn't know your custom-compiled libraries exist. /usr/local/lib might not be in the library search path either. Do the following as root:

Code:

# echo "/usr/local/lib" >> /etc/ld.so.conf
# ldconfig

The above command will append the directory /usr/local/lib to the /etc/ld.so.conf file, creating it if necessary. ldconfig updates the system's cache on libraries installed.

Hope this helps.

the freebsd forum search is hopeless really, but the OS is great.

it still didn't work!

the man pages of ldconfig mention /etc/ld-elf.so.conf

FINALLY

ldconfig /usr/local/lib

it works!

freebsd# ./skipfish
skipfish version 1.31b by
[-] PROGRAM ABORT : Scan target not specified (try -h for help).
Stop location : main(), skipfish.c:394
freebsd#

the man page of ldconfig reads:

SYNOPSIS
ldconfig [-32] [-aout | -elf] [-Rimrsv] [-f hints_file]
[directory | file ...]

DESCRIPTION
The ldconfig utility is used to prepare a set of ``hints'' for use by the
dynamic linker to facilitate quick lookup of shared libraries available
in multiple directories. It scans a set of built-in system directories
and any directories specified on the command line (in the given order)
looking for shared libraries and stores the results in a system file to
forestall the overhead that would otherwise result from the directory
search operations the dynamic linker would have to perform to load the
required shared libraries.

Files named on the command line are expected to contain directories to
scan for shared libraries.....

FreeBSD ports

2010-04-15T15:18:00.000+08:00

for example, if i want to install bash shell

become root
cd /usr/ports/shells/bash
make install

OR

make HTTP_PORT=192.168.0.100:8080 install if you are behind a proxy. Of course, in this case, the proxy is 192.168.0.100.

vbscript

2010-03-25T13:21:00.000+08:00

username

Set WshNetwork = WScript.CreateObject("WScript.Network")
WScript.Echo "Username :" & WshNetwork.UserName

concatenation

use & to concatenate strings, for example,

FilePath = strPath & WshNetwork.UserName & ".V2\ntuser.dat"

check for existence of a file

Set fso = CreateObject("Scripting.FileSystemObject")
If (fso.FileExists(FilePath)) Then
WScript.Echo FilePath & " exists"
End If

check for a value in a registry key
Unlike other programming languages, you need to read the "Err". I wonder why MS don't implement return value. funny.

strValueName = "HKCU\abc\def"

Set WshShell = WScript.CreateObject("WScript.Shell")
On Error Resume Next

WshShell.RegRead(strValueName)

If Err = -2147024894 Then
'The key "HKCU\abc\def" does not exist
End If

If Err = 0 Then
'The key exist
End If

Executing a command
Set WshShell = CreateObject("WScript.Shell")
'encrypt Z: drive using EFS
Set oExec = WshShell.Exec("cipher /e /s:z:")

VirtualBox

2009-11-13T12:07:00.000+08:00

VirtualBox on OpenSuse 11.1

i have windows 7 running as guest using KVM in my opensuse, but i don't like the SVGA emulation.

So i try virtualbox, and i convert the qemu image to vmware image and use it in VirtualBox , but it failed.

opensuse:/kvm-disk # qemu-img convert -O vmdk hp-win7.img hp-win7.vmdk

So i configure a new vdi image for my windows 7 guest and start my vm, but i got an error, and the error advise me to run this:

opensuse:/kvm-disk # /etc/init.d/vboxdrv setup
Stopping VirtualBox kernel module done
Recompiling VirtualBox kernel module failed
(Look at /var/log/vbox-install.log to find out what went wrong)

opensuse:/kvm-disk # more /var/log/vbox-install.log
Makefile:174: *** Error: unable to find the include directory for your current L
inux kernel. Specify KERN_INCL= and run Make again. Stop.

opensuse:/kvm-disk # ls -la /dev/vboxdrv
ls: cannot access /dev/vboxdrv: No such file or directory

opensuse:/kvm-disk # uname -a
Linux opensuse 2.6.27.7-9-pae #1 SMP 2008-12-04 18:10:04 +0100 i686 i686 i386 GNU/Linux

so i install the kernel source for 2.6.27-9.1 using Yast although 2.6.27.37 is available...

opensuse:/kvm-disk # /etc/init.d/vboxdrv setup
Stopping VirtualBox kernel module done
Recompiling VirtualBox kernel module done
Starting VirtualBox kernel module done
opensuse:/kvm-disk #

seems to work...

Cloning a virtualbox VM

you install virtualbox, and install , say windows 2008, as a guest. then u realise you need to install another windows 2008 guest. do u need to install again? No. u can clone the first one. And there is no need to run NewSID on the cloned vm, yes, it is true, read it here http://blogs.technet.com/markrussinovich/archive/2009/11/03/3291024.aspx.

here is how i did it:

C:\Users\chan\.VirtualBox\HardDisks>"C:\Program Files\Sun\VirtualBox\vboxman
age" clonehd old.vdi new.vdi
VirtualBox Command Line Management Interface Version 3.0.10
(C) 2005-2009 Sun Microsystems, Inc.
All rights reserved.

0%...10%...20%...30%...40%...50%...60%...70%...80%...90%...100%
Clone hard disk created in format 'VDI'. UUID: 1dfaa26a-2761-4ee4-9cd6-24642f3c8
53e

C:\Users\chan\.VirtualBox\HardDisks>

KVM

2009-11-11T17:58:00.000+08:00

KVM - kernel virtual machine

kvm uses QEMU for device emulation. So your guest will only see a VGA graphics card. Don't expect good performance here. I increase the resolution to 1024 and i could get a larger screen, but it will be better when qemu emulate some better graphicscard. Xen-HVM uses QEMU for emulation too. I tried -vga vmware in kvm-qemu, but it is worse than no specifying anything (i.e. using the default).

I run a vncserver (RealVNC) in my Windows 7 guest and connect to it from my Linux host using vncviewer, the performance sucks!! it is slow. So there is no need to use vnc to connect to your guest. But I tried Microsoft remote desktop , mstsc.exe, to connect to my Windows 2008 server guests, the results is great. You won't know you are on a VM.

Qemu allows your guests to use the usb port too.

bridge - linux

2009-11-02T13:51:00.001+08:00

http://www.linuxfoundation.org/en/Net:Bridge

qemu

http://qemu-buch.de/cgi-bin/moin.cgi/QemuAndTuntap

hacking

2009-10-23T10:13:00.000+08:00

origami is a Ruby framework designed to parse, analyze, edit, manipulate, forge, exploit PDF files. This is NOT a PDF rendering library. It aims at providing a scripting tool to generate and/or analyz...

http://packetstorm.linuxsecurity.com/UNIX/utilities/origami-1.0.0-beta1.tar.gz

printing from opensuse to fuji xerox ApeosPort 450I

2009-10-09T18:41:00.000+08:00

opensuse 11.1 detects all the nework printers automatically. impressive!

but there is no driver for this printer and i could not find the ppd file for it. ppd - PostScript Printer Description

i use Xerox DocuPrint 4508 Foomatic/lj4dith, and it works!!!!

i managed to print out a beautiful test page... which says Printed Using CUPS v1.3

www.cups.org

btw i use "windows printer via samba" smb://domain-name/servername/printername

and key in your windows domain id and password.

it works!!

iso

2009-10-08T15:30:00.000+08:00

all about ISO

mount an iso file to a folder

mount -t iso9660 -o loop /home/fs/cd101.iso /mnt

If this don't work...

First of all, you'll have to check whether certain options are included in your kernel. If you're using a standard kernel from one of the major distributions, it's pretty likely that everything necessary is already included so you might want to skip this step. If you have a self-compiled kernel - and I recommend everyone to compile the kernel oneself - you'll have to enable the following options in your kernel:

in Device Drivers > Block Devices
  Loopback device support

in File Systems > CD-ROM/DVD Filesystems
  ISO 9660 CDROM file system support
  [*]   Microsoft Joliet CDROM extensions
  [*]   Transparent decompression extension

http://steinsoft.net/index.php?site=Programming/Articles/linux-mountiso

kvm with opensuse

2009-10-05T17:31:00.000+08:00

using kvm on opensuse 11.1 is easy.

http://www.linux-kvm.org/page/HOWTO

my hardware: hp elitebook 6930p

install opensuse 11.1

boot cd with acpi=off

don't use auto configuration during the install process

i disable auto login too and did an internet update and it is so slow... mainly i guess due to my bb connection.. it keep breaking..

so u can skip internet update

to install KVM follow this:

http://en.opensuse.org/KVM

I installed windows 2008 server using a 10gb image file.

create image file

qemu-img create -f qcow2 disk.img 10G

How do I use dd command to create an ISO image?

Put CD into CDROM

Do not mount CD. Verify if cd is mounted or not with mount command:

# mount

If cd was mouted automatically unmout it with umount command:

# umount /dev/cdrom

# umount /mnt/cdrom

Create CD-ROM ISO image with dd command:

# dd if=/dev/cdrom of=/tmp/cdimg1.iso

Where,

if=/dev/cdrom: Read from /dev/cdrom (raw format)
of=/tmp/cdimg1.iso: write to FILE cdimg1.iso i.e. create an ISO image

src: http://www.cyberciti.biz/tips/linux-creating-cd-rom-iso-image.html

boot the guest from a iso file

qemu-kvm -m 256 -hda disk.img -cdrom winxpsp2.iso -boot d

-boot d instruct qemu to boot from cdrom

what nic are supported?

qemu-kvm -hda vista1.img -net nic,model=?,macaddr=00:16:3e:23:38:45 -net user -cdrom BootMedia.iso -boot d &

opensuse:/kvm-disk # qemu: Supported ISA NICs: ne2k_isa
qemu: Supported PCI NICs: i82551 i82557b i82559er ne2k_pci pcnet rtl8139 e1000 virtio

i82557b is supported by my vista

Insert KVM Modules

Insert the kvm modules as follows (as root)

For Intel processors

opensuse11:~ # modprobe kvm
opensuse11:~ # modprobe kvm-intel

For AMD processors

opensuse11:~ # modprobe kvm
opensuse11:~ # modprobe kvm-amd

To confirm the modules OK,

opensuse11:~ # lsmod | grep kvm
kvm_intel 67824 0
kvm 182936 1 kvm_intel

However, this setting lost on a reboot.

To insert this module at boot time, Click Computer – YaST – System – “/etc/sysconfig editor”. This launches the sysconfig editor.

Click “+” next to “system” and then “+” next to Kernel. Click “MODULES_LOADED_ON_BOOT“, in the right-pane, enter “kvm kvm-intel kqemu” without quotes (”kvm kvm-amd kqemu” for AMD) in the setting box and click finish. Click OK on the confirmation window.

Now, we are all set to configure and run a guest OS on your openSUSE.

Installation of Windows guest paravirtual network drivers

opensuse:/kvm-disk # qemu-kvm -hda AD.img -cdrom /home/fs/Desktop/NETKVM-20081229.iso -net nic,model=virtio
Warning: vlan 0 is not connected to host network

AD.img is the image file where i had installed a windows 2008 to function as the Domain Controller

-cdrom /home/fs/Desktop/NETKVM-20081229.iso

The iso file contained the paravirtualized network drivers that i downloaded; when the Windows 2008 boot up, the cdrom drive will behave as if there is a CD containing the drivers needed for installation.

install tap network interface

install openvpn

create 4 tap - tap0 - 3

opensuse:/etc # openvpn --mktun --dev tap0
Mon Oct  5 23:33:23 2009 TUN/TAP device tap0 opened
Mon Oct  5 23:33:23 2009 Persist state set to: ON
opensuse:/etc # openvpn --mktun --dev tap1
Mon Oct  5 23:43:39 2009 TUN/TAP device tap1 opened
Mon Oct  5 23:43:39 2009 Persist state set to: ON
opensuse:/etc # openvpn --mktun --dev tap2
Mon Oct  5 23:43:42 2009 TUN/TAP device tap2 opened
Mon Oct  5 23:43:42 2009 Persist state set to: ON
opensuse:/etc # openvpn --mktun --dev tap3
Mon Oct  5 23:43:46 2009 TUN/TAP device tap3 opened
Mon Oct  5 23:43:46 2009 Persist state set to: ON
opensuse:/etc #

ifconfig tap0 up

brigde network
opensuse:/etc # brctl addbr br0
opensuse:/etc # brctl show
bridge name bridge id  STP enabled interfaces
br0  8000.000000000000 no

opensuse:/etc # brctl addif br0 eth0
opensuse:/etc # brctl addif br0 tap0
opensuse:/etc # brctl addif br0 tap1
opensuse:/etc #

opensuse:/etc # brctl show
bridge name bridge id  STP enabled interfaces
br0  8000.0025b32ead04 no  eth0
tap0
tap1
opensuse:/etc #


opensuse:/etc # vi /etc/sysconfig/network/scripts/ifcfg-br0
DEVICE=br0
TYPE=Bridge
BOOTPROTO=dhcp
ONBOOT=yes

opensuse:/etc # vi /etc/sysconfig/network/scripts/ifcfg-eth0
DEVICE=eth0
BRIDGE=br0 
BOOTPROTO=dhcp
HWADDR=00:19:b9:7e:c8:63
ONBOOT=yes
TYPE=Ethernet
USERCTL=no
IPV6INIT=no
PEERDNS=yes
NM_CONTROLLED=no


opensuse:/etc # vi /etc/sysconfig/network/scripts/qemu-ifup
#!/bin/sh
switch=$(/sbin/ip route list | awk '/^default / { print $NF }')
/sbin/ifconfig $1 0.0.0.0 up
/usr/sbin/brctl addif ${switch} $1


opensuse:/etc/sysconfig/network/scripts # chmod o+x qemu-ifup
opensuse:/etc/sysconfig/network/scripts # chmod o+x ifcfg-br0
opensuse:/etc/sysconfig/network/scripts # chmod o+x ifcfg-eth0



opensuse:/etc # /etc/rc.d/network restart
Shutting down the NetworkManager                                     done
Shutting down network interfaces:
br0
    No configuration found for br0
    Nevertheless the interface will be shut down.          done
eth0      device: Intel Corporation 82567LM Gigabit Network Connection (rev 03)                                                                  done
tap0
    No configuration found for tap0
    Nevertheless the interface will be shut down.
could not find configuration file ifcfg-tap0
tap0      tunctl not available -- install tunctl or uml-utilitiesdone
tap1
    No configuration found for tap1
    Nevertheless the interface will be shut down.
could not find configuration file ifcfg-tap1
tap1      tunctl not available -- install tunctl or uml-utilitiesdone
tap2
    No configuration found for tap2
    Nevertheless the interface will be shut down.
could not find configuration file ifcfg-tap2
tap2      tunctl not available -- install tunctl or uml-utilitiesdone
tap3
    No configuration found for tap3
    Nevertheless the interface will be shut down.
could not find configuration file ifcfg-tap3
tap3      tunctl not available -- install tunctl or uml-utilitiesdone
wlan0     device: Intel Corporation Wireless WiFi Link 5100      done
Shutting down service network  .  .  .  .  .  .  .  .  .             done
Starting the NetworkManager                                          done
opensuse:/etc #

http://www.linux-kvm.com/content/tip-how-get-maximum-network-performance-using-paravirtual-drivers-and-bridged-networking

adding tap devices using YaST

u must disable network manager from managing the network and use if-up, if-down...

persistent tunnel

no tunnel group , no tunnel owner

must install tunctl package

for me, i need to add my proxy server in YaST control centre->network services->proxy

opensuse:/kvm-disk # ifup br0
br0
br0 Ports: [eth0] [tap0] [tap1] [tap2] [tap3]
br0 forwarddelay (see man ifcfg-bridge) ... ready
Starting DHCP4 client on br0.
br0 IP address: 192.168.0.248/24
opensuse:/kvm-disk # ifconfig
br0 Link encap:Ethernet HWaddr 00:25:B3:2E:AD:04
inet addr:192.168.0.248 Bcast:192.168.0.255 Mask:255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:367 errors:0 dropped:0 overruns:0 frame:0
TX packets:78 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:77192 (75.3 Kb) TX bytes:20045 (19.5 Kb)

eth0 Link encap:Ethernet HWaddr 00:25:B3:2E:AD:04
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:26093 errors:0 dropped:0 overruns:0 frame:0
TX packets:10256 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:100
RX bytes:19994866 (19.0 Mb) TX bytes:1176611 (1.1 Mb)
Memory:90400000-90420000

lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:172 errors:0 dropped:0 overruns:0 frame:0
TX packets:172 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:14060 (13.7 Kb) TX bytes:14060 (13.7 Kb)

tap0 Link encap:Ethernet HWaddr C2:14:C7:5D:74:40
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:401 overruns:0 carrier:0
collisions:0 txqueuelen:500
RX bytes:0 (0.0 b) TX bytes:0 (0.0 b)

tap1 Link encap:Ethernet HWaddr 32:54:9D:9C:03:88
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:401 overruns:0 carrier:0
collisions:0 txqueuelen:500
RX bytes:0 (0.0 b) TX bytes:0 (0.0 b)

tap2 Link encap:Ethernet HWaddr 3E:11:FD:E3:87:A8
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:401 overruns:0 carrier:0
collisions:0 txqueuelen:500
RX bytes:0 (0.0 b) TX bytes:0 (0.0 b)

tap3 Link encap:Ethernet HWaddr F6:6B:17:54:E3:4D
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:401 overruns:0 carrier:0
collisions:0 txqueuelen:500
RX bytes:0 (0.0 b) TX bytes:0 (0.0 b)

wlan0 Link encap:Ethernet HWaddr 00:21:6A:3B:EF:06
UP BROADCAST MULTICAST MTU:1500 Metric:1
RX packets:24 errors:0 dropped:0 overruns:0 frame:0
TX packets:14 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:2034 (1.9 Kb) TX bytes:5060 (4.9 Kb)

wmaster0 Link encap:UNSPEC HWaddr 00-21-6A-3B-EF-06-00-00-00-00-00-00-00-00-00-00
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:0 (0.0 b) TX bytes:0 (0.0 b)

opensuse:/kvm-disk #

opensuse:/kvm-disk # qemu-kvm -hda AD.img -net nic,model=virtio,macaddr=00:11:22:33:44:55:00 -net tap invalid syntax for ethernet address

opensuse:/kvm-disk # qemu-kvm -hda AD.img -net nic,model=virtio,macaddr=00:11:22:33:44:55:00 -net tap
invalid syntax for ethernet address

opensuse:/kvm-disk # qemu-kvm -hda AD.img -net nic,model=virtio,macaddr=00:16:3e:23:38:43 -net tap
/etc/qemu-ifup: could not launch network script
Could not initialize device 'tap'

opensuse:/kvm-disk # qemu-kvm -hda AD.img -net nic,model=virtio,macaddr=00:16:3e:23:38:43 -net tap0 Unknown network device: tap0

opensuse:/kvm-disk # qemu-kvm -hda AD.img -net nic,model=virtio,macaddr=00:16:3e:23:38:43 -net tap,script=/etc/sysconfig/network/scripts/qemu-ifup
/etc/sysconfig/network/scripts/qemu-ifup: line 4: /usr/sbin/brctl: No such file or directory
/etc/sysconfig/network/scripts/qemu-ifup: could not launch network script
Could not initialize device 'tap'

opensuse:/kvm-disk # which brctl
/sbin/brctl

opensuse:/kvm-disk # vi /etc/sysconfig/network/scripts/qemu-ifup

opensuse:/kvm-disk # qemu-kvm -hda AD.img -net nic,model=virtio,macaddr=00:16:3e:23:38:43 -net tap,script=/etc/sysconfig/network/scripts/qemu-ifup

i use static ip within the Windows 2008 guest.

qemu-kvm and qemu-***

from http://wiki.archlinux.org/index.php/QEMU:
For versions of QEMU prior to 0.10.2-1 use the qemu-kvm executable. For 0.10.2-1 and later, use qemu --enable-kvm.

my qemu is

opensuse:/kvm-disk # qemu|grep version
QEMU PC emulator version 0.9.1, Copyright (c) 2003-2008 Fabrice Bellard

Windows Guest Drivers
network drivers - NetKVM - http://people.redhat.com/~yvugenfi/24.09.2009/NetKVM.zip
Storage drivers - viostor - http://people.redhat.com/~yvugenfi/24.09.2009/viostor.zip

http://www.linux-kvm.com/content/latest-release-windows-virtio-network-drivers
http://www.linux-kvm.com/content/upgrading-windows-paravirtual-network-drivers
http://www.linux-kvm.com/content/tip-how-setup-windows-guest-paravirtual-network-drivers

http://www.linux-kvm.com/content/using-windows-installer-paravirtual-network-drivers

change cdrom in QEMU

ctr - alt - 2 to go to console (lef control - left alternate and 1 )
type info block to view device status
type change ide1-cd0 /path/soemthing.iso OR change ide1-cd0 /dev/cdrom
info block

to go back , control - alternate - 1

Ref
http://qemu-buch.de/cgi-bin/moin.cgi/QemuAndTuntap

http://www.susegeek.com/virtualization/howto-install-configure-kvm-virtualization-run-guest-oses-in-opensuse/

http://qemu-buch.de/cgi-bin/moin.cgi/QemuAndTuntap

fonts

2009-10-03T15:20:00.000+08:00

http://www.microsoft.com/typography/default.mspx

embedding fonts

http://www.netmechanic.com/news/vol3/css_no15.htm

http://www.morovia.com/font/support/embed-font-web.asp

windows server 2008 - different versions

2009-09-21T15:45:00.001+08:00

go here http://www.microsoft.com/windowsserver2008/en/us/r2-editions-overview.aspx to find the differences between the different versions...

to run certificate services, u will need the Enterprise version...

if you run it under XenServer, you will be forced to use a harddisk image of 24GB, even though the XenServer manual state that 10GB is the minimum for server 2008.

xen live cd - adding windows guests

2009-09-20T19:03:00.000+08:00

download xen live cd image and burn it to a cd and boot the cd in your computer

it took ten min to boot in my case.

i have a 160 GB harddisk, with one 1GB NetBSD partition; the rest are not partitioned.

i want to install windows on Xen.

add a partition
after you have boot the Xen live CD, cretate a partition by running fdisk.

fdisk /dev/sda (sd means SCSI but i am sure my harddisk is not SCSI)

n
p

i added a primary parition of 50GB

create a filesystem for the partition
mkfs -t ext3 /dev/sda2

mount it
mount /dev/sda2 /mnt

to be continued....

netbsd

2009-09-19T18:34:00.000+08:00

managed to install netbsd on my hp laptop EliteBok 6930p.

sometimes this laptop gives problem with ACPI.

netbsd will boot normal with ACPI enabled.. and the timeout is very fast... not enough for u to select to boot "boot netbsd -2" to disable ACPI

so what u can do here is :

edit /boot.cfg

and consult http://netbsd.gw.com/cgi-bin/man-cgi?boot.cfg++NetBSD-current the web man page on the boot.cfg

for me, i have to change default=1 to default=3

Xen using netbsd

2009-09-19T16:14:00.001+08:00

need to install multiple Window servers on my laptop for some testing... one domain controller, one offering certificate service (pki), one as file server, and one Vista as client...

i can't imagine using type 1 hypervisor for this task... i only have 2G RAM on my laptop.. so virtualbox and vmware server is out..

i am left with Xen and VMware ESX Server , but the latest ESX server only runs on 64bit hardware and it don't support intel cpu with emt64 extension... while at least this is what i found, i maybe wrong as i don't have much time ...

so i move on to using Xen... either ubuntu and debian... ubuntu does not offer dom0 kernel now and i saw many criticism on running Xen with Ubuntu..

i did tried it out but it is some troublesome and time is running short

so i went to debian... but debian didn't install on my HP EliteBook... oh ...

i will try netbsd now... i always prefer *bsd more...

Xen

2009-09-12T16:44:00.000+08:00

Ganeti
Ganeti is a cluster virtual server management software tool built on top of existing virtualization technologies such as Xen or KVM and other Open Source software.
http://code.google.com/p/ganeti/

http://www.serverwatch.com/news/article.php/3770221/Hypervisor-Face-Off-KVM-vs-Xen-vs-VMware.htm

"KVM benchmarking is extremely selective," Crosby commented. "Where it does benefit in performance, it does so by sacrificing what we view as fundamental security concerns for enterprise virtualization deployments. Xen's deep separation of trust domains costs a bit in performance but provides the hard-line separation required for any secure deployment of virtualization."

Bruce also noted KVM relies on strong CPU performance with very limited support for para-virtualization. As such, Bruce argued it is difficult to achieve top performance in a KVM virtualized environment without powerful hardware underneath. Conversely, in his view, Xen offers strong support for para-virtualization for modified Windows guests and modified Linux guests to achieve near-native performance.

http://virt.kernelnewbies.org/TechComparison - features and performance of the various virtualization technologies available for Linux

Diff between para virtualization and hardware assisted virtualization

To run OS unmodified on Xen , u need a cpu that support hardware virtualization. You need to use HVM in Xen to run Windows.

http://www.virtuatopia.com/index.php/An_Overview_of_Virtualization_Techniques

xen live cd
http://wiki.xensource.com/xenwiki/LiveCD
Xenoppix http://unit.aist.go.jp/itri/knoppix/xen/index-en.html

installing Windows on Xen
http://www.virtuatopia.com/index.php/Virtualizing_Windows_Server_2008_with_Xen
http://mediakey.dk/~cc/howto-install-windows-xp-vista-on-xen/

wifi
http://wiki.xensource.com/xenwiki/XenWifi - sharing a wireless nic between dom0 and domU.

You might need http://ebtables.sourceforge.net/ if your wireless NIC does not allow packets with a MAC that is different from its own.

Xen setup docs that i found:

http://www.virtuatopia.com/index.php/Xen_Virtualization_Essentials

Xen on OpenSuse
http://en.opensuse.org/Installing_Xen3

Xen on Debian 5
http://www.howtoforge.com/virtualization-with-xen-on-debian-lenny-amd64

xen tools http://www.debian-administration.org/articles/533

http://wiki.xensource.com/xenwiki/HowTos
http://www.howtoforge.com/perfect_setup_xen3_debian
http://www.packtpub.com/files/Xen-Virtualisation-Sample-Chapter-Chapter-2-Running-Xen.pdf
http://www.howtoforge.com/xen_gui_fedora_7_desktop

How to Add JARs to Project Build Paths in Eclipse (Java)

2009-09-05T13:44:00.000+08:00

see http://www.wikihow.com/Add-JARs-to-Project-Build-Paths-in-Eclipse-%28Java%29

Google App Engine

2009-09-04T14:31:00.000+08:00

Deploying app engine to your own domain

http://code.google.com/appengine/articles/domains.html

basically you need to use Google Apps to manage your domains and point it to your App Engine application.

i have to wait for 15 minutes before my domain points to my app engine.

i register my domain with godaddy through google, and the cname records are added automatically when you add them in Google Apps.

Using Google Account to authenticate users

making use of Google Account has the advantage of offloading the user authentication to Google. You are left with more time to develop your web application.

There are several ways to force users to authenticate.

servlet

http://code.google.com/appengine/docs/java/users/overview.html go to "Using Google Accounts in Java" section

web.xml

please see http://code.google.com/appengine/docs/java/config/webxml.html#Security_and_Authentication

jsp

http://code.google.com/appengine/docs/java/javadoc/com/google/appengine/api/users/package-summary.html

Package com.google.appengine.api.users
The UserService provides facilities to check whether a user has authenticated using their Google Account, retrieve their email address, and check whether they are an administrator for this application.

See:
Description

Interface Summary
UserService The UserService provides information useful for forcing a user to log in or out, and retrieving information about the user who is currently logged-in.

Class Summary
User User represents a specific user, represented by the combination of an email address and a specific Google Apps domain (which we call an authDomain).
UserServiceFactory Creates a UserService.

Exception Summary
UserServiceFailureException UserServiceFailureException is thrown when any unknown error occurs while communicating with the user service.

Package com.google.appengine.api.users Description

The UserService provides facilities to check whether a user has authenticated using their Google Account, retrieve their email address, and check whether they are an administrator for this application. It can also be used to construct a URL for users to login or logout. More information is available in the on-line documentation.

As an example, your application might, in a JSP file, have code like this:

<%
UserService userService = UserServiceFactory.getUserService();
if (!userService.isUserLoggedIn()) {
%>
Please %>">log in>
<% } else { %>
Welcome, <%= userService.currentUser().getNickname(); %>!
( %>">log out>)
<%
}
%>

about master boot record - mbr

2009-09-01T19:42:00.000+08:00

just got a task that involves mbr, so i manage to find some good links on mbr...

Assembly code on how to read boot sector
http://bootmaster.filerecovery.biz/appnote4.html

backing up mbr using the dd command, but only for Unix*
http://www.freesoftwaremagazine.com/columns/backing_up_your_master_boot_record
dd if=/dev/hda of=/home/richmondg/mbr_backup bs=512 count=1

dd if=/dev/sda of=mbr.bin bs=512 count=1

http://www.ntfs.com/mbr.htm say the mbr is always at track (cylinder) 0, side (head) 0, and sector 1.

NAT mode and port forwarding

2009-08-19T20:18:00.000+08:00

I am runnig Debian as guest in my VirtualBox in Windows and i want to ssh to Debian.

How ?

run debian in NAT mode and do port forwarding

go to C:\Program Files\Sun\xVM VirtualBox and run

VBoxManage setextradata "debian 5 Lenny" "VBoxInternal/Devices/pcnet/0/LUN#0/Config/guestssh/Protocol" TCP
VBoxManage setextradata "debian 5 Lenny" "VBoxInternal/Devices/pcnet/0/LUN#0/Config/guestssh/GuestPort" 22
VBoxManage setextradata "debian 5 Lenny" "VBoxInternal/Devices/pcnet/0/LUN#0/Config/guestssh/HostPort" 22

restart your guest

run the below to see what u have done:
VBoxManage getextradata "debian 5 Lenny" "VBoxInternal/Devices/pcnet/0/LUN#0/Config/guestssh/Protocol"
VBoxManage getextradata "debian 5 Lenny" "VBoxInternal/Devices/pcnet/0/LUN#0/Config/guestssh/GuestPort"
VBoxManage getextradata "debian 5 Lenny" "VBoxInternal/Devices/pcnet/0/LUN#0/Config/guestssh/HostPort"

The info is actually stored in C:\Users\who am i\.VirtualBox\Machines\debian 5 Lenny\debian 5 Lenny.xml

here is part of the xml file:

name="VBoxInternal/Devices/pcnet/0/LUN#0/Config/guestssh/GuestPort" value="22"/>

name="VBoxInternal/Devices/pcnet/0/LUN#0/Config/guestssh/HostPort" value="22"/>

debian 5 Lenny is the name of your guest, it is case sensitive.

from the Help:

The above example assumes a PCNet virtual network card; if you have configured the guest to use the Intel PRO/1000, replace

"pcnet" with "e1000" in the above commands. Similarly, if you want to configure a different interface instance replace the /0/

with the appropriate index. pcnet and e1000 are counted separately in this respect, and counting starts at 0 for both types.

The name guestssh is an arbitrary one chosen for this particular forwarding configuration. With that configuration in place, all

TCP connections to port 2222 on the host will be forwarded to port 22 on the guest. Protocol can be either of TCP or UDP (these

are case insensitive). To remove a mapping again, use the same commands, but leaving out the values (in this case TCP, 22 and

2222).

It is not possible to configure incoming NAT connections while the VM is running. However you can change the settings for a VM

which is currently saved (or powered off at a snapshot).

remember u need to restart your guest...

from windows: ssh to 127.0.0.1:22

hacking cisco network

2009-08-17T06:00:00.000+08:00

Polyphemus - Polyphemus is an SNMP-based explorer and visualizer of OSPF networks

http://www.dia.uniroma3.it/~compunet/www/view/tool.php?id=polyphemus

using aptitude on Debian 5 (Lenny)

2009-08-17T05:18:00.000+08:00

To me, using Linux is always difficult, having get used to FreeBSD...

I just don't undertstand why all those man pages could not be written with more examples...

anyway, i installed Debian 5 and wanted to install IPRAS.

aptitude could not find the package, but a search on google shows that the package exists..

http://packages.debian.org/lenny/irpas

This page advise adding "deb http://ftp.de.debian.org/debian lenny main non-free
" to /etc/apt/sources.list

but I think they miss out something.

This is what I added in my /etc/apt/sources.list :

deb http://ftp.de.debian.org/debian lenny main non-free
deb-src http://ftp.de.debian.org/debian lenny main non-free

I run "aptitude install ipras" and again it complained package not found

more googling for aptitude tutorial and found this

http://algebraicthunk.net/~dburrows/projects/aptitude/doc/en/ch01s01s05.html

so i must run aptitude and type u to do an update.

after the update, "aptitude install ipras" runs and ipras was installed!!!