20 Linux System Monitoring Tools Every SysAdmin Should Know

http://www.cyberciti.biz/tips/top-linux-monitoring-tools.html

Understanding VirtualCenter Performance Statistics

http://communities.vmware.com/docs/DOC-5230

Howto use VMware esxtop

Official documentation http://www.vmware.com/info?id=193

Nice article http://www.hypervizor.com/2009/06/interactive-replay-batch-esxtop-modes/

Killing a frozen VM on a vSphere ESX host

http://itknowledgeexchange.techtarget.com/virtualization-pro/killing-a-frozen-vm-on-a-vsphere-esx-host/?track=NL-915&ad=710968HOUSE&asrc=EM_NLN_8048495&uid=5373778

PERL Getopt and GetOptions

When you code unix program first of all you need to get user options. Two Perl modules (Getopt and Getoptions::Long) work to extract program flags and arguments much like Getopt and Getopts do for shell programming. The Perl modules, especially GetOptions::Long, are much more powerful and flexible.

See full article at http://aplawrence.com/Unix/perlgetopts.html

Ultimate Deployment Appliance

Unattended OS installations (Windows, Linux, ESX, Solaris) over the network set-up in minutes! Look at http://www.ultimatedeployment.org/

How to shutdown windows from linux

If you have samba you can use "net rpc SHUTDOWN -C "some comment here" -f -I x.x.x.x -U user_name%password"

Howto install Windows XP on ESX3

http://virtrix.blogspot.com/2007/09/vmware-installing-windows-xp-on-esx.html

How to copy (backup) files from ESX3i?

You can use RCLI and vifs command. More info at
http://www.vm-help.com/esx/esx3i/esx_3i_rcli/vifs.php

Examples:
List files in datastore directory:
vifs --server 192.168.4.4 --username root --password ***** --dir "[Datastore1]/win2k3"

Download file from ESX3i Datastore:
vifs --server 192.168.4.4 --username root --dc ha-datacenter --password ***** --get "[Datastore1] /win2k3/win2k3-flat.vmdk" my-clone.vmdk

Notes:
File write speed around 1MBps only

Using Linux shell scripts to automatically create VMware ESX 3.5 hosts

http://searchvmware.techtarget.com/tip/0,289483,sid179_gci1351853_mem1,00.html?track=NL-915&ad=697266&asrc=EM_NLN_6437813

On demand VNC server with GDM

Each user can login (via ssh) to *nix server and start vncserver. Then he can login to X11 desktop via VNC viewer with defined vnc password. But it's far far away from nice solution. Much better solution is to setup vncserver as xinetd service.

First of all you have to define new service in particular port. Add line bellow into /etc/services

vnc1024         5901/tcp                        # VNC & GDM

now create service description for xinetd. Go to directory /etc/xinetd.d

cd /etc/xinetd.d

and create file vnc1024

service vnc1024
{
     disable = no
     socket_type = stream
     protocol = tcp
     wait = no
     user = nobody
     server = /usr/bin/Xvnc
     server_args = -inetd -query localhost -geometry 1024x800 -depth 16 -once -fp unix/:7100 -securitytypes=none
}

Move to runlevel 3

init 3

Restart xinetd

/etc/init.d/xinetd

Move back to runlevel 5

init 5

And that's it. Now try connect via VNCviewer to port 6901

DR & BC of virtualized datacenters

Virtualization significantly helps to implement Disaster Recovery and Business Continuity scenarios. But some one can think that he can install VMware SRM software and DR&BC solution is ready. It's common mistake. VMware SRM is just arround 5% of DR&BC solution. You have to concider right technology and proper proceses with respect of your particular environment. Right technology means storage replications, network high availabaility across datacenters, automation, etc.

Nice article about VMware implementation conciderations is at http://searchvmware.techtarget.com/tip/0,289483,sid179_gci1347066_mem1,00.html?track=NL-915&ad=689280&asrc=EM_NLN_5870851

Configuration Point-to-Point OpenVPN link

I like OpenVPN because it's simple and it does what you need - VPN.

Let's assume that we have two un*x like servers with OpenVPN software and regular OS user openvpn in group openvpn. One server has IP address 192.168.4.10 and second 192.168.4.100.

In server 192.168.4.10 use following configuration file (openvpn.conf):
remote 192.168.4.100
ifconfig 10.0.0.1 10.0.0.2
dev tun0
port 5001
proto udp
secret /usr/local/etc/openvpn/secret.key
ping 10
comp-lzo
verb 5
mute 10
user openvpn
group openvpn

In server 192.168.4.100 use following configuration file (openvpn.conf):
remote 192.168.4.10
ifconfig 10.0.0.2 10.0.0.1
dev tun0
port 5001
proto udp
secret /usr/local/etc/openvpn/secret.key
ping 10
comp-lzo
verb 5
mute 10
user openvpn
group openvpn

In one of this two servers create secret.key by issuing following command:
openvpn --genkey --secret /usr/local/etc/openvpn/secret.key

Finaly:
Somehow (for example scp) copy secret key to second server into correct location and run openvpn daemons on both servers. On servers new network interface appears (tap) with IP addresses (10.0.0.1 and 10.0.0.2) and you can ping these 10.0.0.1-2 IP addresses over secure VPN link.

Here we go.

Scripting reference manuals

Command line reference for Windows, Bash, Oracle, and SQL Server
http://www.ss64.com/index.html

Creating the 64 KB aligned partition with Diskpart.exe

Once you are at the command prompt, use Diskpart.exe to create an aligned partition. To do so, type in the following:

diskpart
select disk 0
create partition primary align=64

You can now exit diskpart by typing 'exit'.

How to print to a network printer from an MS-DOS-based program in Windows XP

http://support.microsoft.com/kb/314499

Newbie SysAdmin Guide to Solaris

http://www.unixville.com/~moazam/stories/2004/05/17/newbieSysadminGuideToSolaris.html

EMC Cellera Simulator

http://virtualgeek.typepad.com/virtual_geek/2008/08/celerra-virtual.html

Top 10 PowerShell scripts that VMware administrators should use

Top 10 PowerShell scripts that VMware administrators should use

By Eric Siebert
published: Wednesday, December 10 2008

http://www.virtual-strategy.com/Eric-Siebert-s-Top-10/Top-10-PowerShell-scripts-that-VMware-administrators-should-use.html

iSCSI on FreeBSD

FreeBSD iSCSI howto
http://www.cyberciti.biz/faq/freebsd-iscsi-initiator-howto/

FreeBSD network link agregation
http://www.freebsd.org/doc/en/books/handbook/network-aggregation.html