I believe the Next Generation Computing is Software Defined Infrastructure on top of the robust physical infrastructure. You can ask me anything about enterprise infrastructure (virtualization, compute, storage, network) and we can discuss it deeply on this blog. Don't hesitate to contact me.
Wednesday, October 13, 2010
Thursday, September 30, 2010
Wednesday, September 29, 2010
How CISCO UCS can help to Disaster and Recovery
Part 1: http://www.youtube.com/watch?v=2R9oWMBOAow
Part 2: http://www.youtube.com/watch?v=9pEtR8eNUYI
Friday, September 24, 2010
LANAMARK
http://www.lanamark.com/
I would like to install it and compare against Platespin Recon.
Wednesday, September 22, 2010
Sunday, September 19, 2010
Microsoft NLB Cluster on VMware
http://support.microsoft.com/kb/323437
http://support.microsoft.com/kb/323431
VMware Resources
http://www.vmware.com/files/pdf/implmenting_ms_network_load_balancing.pdf
http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1006580
http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1556
Friday, September 17, 2010
Tuesday, September 14, 2010
EMC Unified Storage – Next Generation Efficiency Details
Monday, August 30, 2010
Thursday, August 19, 2010
Tuesday, June 29, 2010
How to remove Cisco Nexus 1000V plugin
--- COPY STARTS HERE ---
The Cisco Nexus 1000V switch is a pure software implementation of a Cisco Nexus switch. It resides on a server and integrates with the hypervisor to deliver VN-Link virtual machine-aware network services. The Cisco Nexus 1000V switch takes advantage of the VMware vSphere vNetwork Distributed Switch framework to offer tightly integrated network services as part of both a server virtualization strategy and a broader data center virtualization strategy. In addition, the switch provides operations and management consistency with existing Cisco Nexus and Cisco Catalyst switches.
Here I would like to share how to remove Cisco Nexus 1000V Plugin
1. To view the extension key on the vCenter Server, open an Internet Browser, and enter the URL path http://
2. Authentication dialog box open, Enter the username and password and click OK
3. The Managed Object Browser (MOB) open the Service Instance page, in the value column of the Properties table, click Content
4. In the Value column of the Properties table, Click extensionManager OR you can open browser with URL http://localhost/mob/?moid=ExtensionManager
5. In the Methods table, click UnregisterExtension6. In the Value of the Parameters table, paste “Cisco_Nexus_1000V_1850055053″ and click Invoke Method.
Note: The actual value of “Cisco_Nexus_1000v_xxxxx” will wary. It should match the extension key from the Cisco_nexus_1000v_extension.xml file.
Enjoy!
Saturday, March 27, 2010
VMware ESX 4 can even virtualize itself
But what if you prefer to run ESX on ESX instead of Workstation?
Full article at:http://www.vcritical.com/2009/05/vmware-esx-4-can-even-virtualize-itself/
Tuesday, March 16, 2010
CFM to BTU formula
A BTU is a British thermal unit, which is the measure of energy to raise one CC of water one degree Celsius.
But you probably want to know about airflow in CFM (not water), and the amount of cooling (or heating) available in 1 cfm or airflow.
In Houston, we tend to cool things more than heat. We also try to drive moisture out of the air (dehumidify), but I won't discuss that now. The general equation to answer your question is like this: Qsens = cfm * 1.08 * (Tin - Tout) <-- "delta T"
You need to determine what your "delta T" is. For cooling a space to 75degF (23.89 degC), your dT is usually 20degF (-6.67 degC) with your supply air temperature (SA=55degF 12.78degC) and your return air temperature (RA=75degF 23.89 degC). This has been idealized and simplified. For cooling, 1cfm will do about 21.6btu/h of cooling. For heating, (SA=90/32.2, RA=68, 1cfm => 23.76btu/h)Citaton from: http://forum.onlineconversion.com/showthread.php?t=701
--------------------------------------
CFM * 1.08 * tRise = Btu/hr
--------------------------------------
General information follows.
That factor is based on standard conditions which are at sea level and A standard humidity level which i do not remember off hand. As altitude increases the factor decreases. At 2100 feet it is roughly 1.0.
The humidity also affects this number. Generally the greater the humidity the greater the factor.
1.08 Will be good enough for most applications though.
I'll give an example of the use:
Suppose the room temperature is 65.
We have a 1200 CFM blower. We measure an output temperature of 100.
100 - 65 = 35 tRise.
Now we have all the numbers to get our BUT/hr.
1200 * 1.08 * 35 = 45,360 btu/hr
This particular problem often compilments another, And that is how do we verify the CFM is as cited or measured with an anemometer.
Assuming we have electric heat and the temperature probe is not in line of site of the heating elements (to be sure we are not measuring the IR radiation) All you need to know is the power consumption. Either measure it with an amp meter. Or go with cited figure(not as accurate).
CFM = btu / (1.08 * tRise)
For reference: 1 kw/hr = 3412.14 btu
assume we have a 15kw heater and a tRise of 22
15kw * 3412.14 = 51182.12 btu
now we can solve for CFM
51182.12 / (1.08 * 22) = 2154.
In that example our result is 2,154 CFM.
If that conflicts with a suspected figure An investigation is required.
Keep in mind the factor is based on standard conditions. As a rule of thumb the result should be within 10% of the calculation. Anything out of this range is a trouble spot. Most likely to be a dirty air filter, or incorrect power factoring.
Monday, March 08, 2010
Monday, March 01, 2010
Tuesday, January 19, 2010
Storage fundamentals
http://www.vmdamentals.com/?p=266
Throughput part 2: RAID types and segment sizes
http://www.vmdamentals.com/?p=296
RAID 10 or RAID 5
I think that good choice depends on required performance, capacity, and data value stored on protected disks. RAID is just one type of protection and other protections should be used. Other data protections are:
- Backup
- Local Disk Replication (Volume Clones - Business Continous Volumes like i.e. EMC SnapView)
- Remote Disk Replications (EMC SAN Copy, EMC SRDF, IBM Metro Mirror, etc.)
So sometimes RAID 5 or 6 makes sense.
Thursday, January 14, 2010
Sunday, January 10, 2010
Tuesday, December 15, 2009
Thursday, December 10, 2009
Wednesday, December 09, 2009
Tuesday, December 08, 2009
EMC Celerra - Virtual Appliance
http://virtualgeek.typepad.com/virtual_geek/2009/04/new-celerra-vsa.html
Monday, December 07, 2009
Saturday, December 05, 2009
Sunday, November 29, 2009
Good film about how to install PowerPath/VE
http://www.youtube.com/watch?v=hDC0EQ-jM_I
Wednesday, November 25, 2009
Platespin Recon - cannot get performance counters?
Regedt32/hklm/currentcontrolset/control/securepipeserver/winreg. -system has full control
Tuesday, November 24, 2009
VMware Converter - P2V
VMware converter uses two types of “cloning” methods during the P2V process:
File level cloning : Performed when you make the volume smaller then original (slowest conversion speed)
Block level cloning : Performed when you maintain or make drives larger (fastest conversion speed)
If you need to see the conversion rate use the VMware Standalone. It will now report the conversion rate as well as conversion type it is using to get your data into the virtual environment.
On my last project conversion speed varied from 144GB/Hr (or 2.4GB/min block lvl copy) to 36GB/Hr (.6GB/min file lvl copy).
Sunday, November 22, 2009
Installing dell openmanage 6.1 on esxi 4.0
...
Here are the exact steps for installing dell openmanage on ESXi 4.0. This is provided in their support site.
1) Download the appropriate RCLI (Remote Command Line Interface) package from http://www.vmware.com/http://www.vmware.com/support/developer/vcli/ depending on whether your system is running on Microsoft Windows or Linux.
2) Copy the Dell OpenManage bundle to a directory on your system.
3) Use the vihostupdate command. If you are using Microsoft Windows, navigate to the folder where you have installed the RCLI utilities to use this command. If you are using Linux, this command is installed when you install the RCLI RPM .
4) Execute the command vihostupdate --server
5) The command output displays a successful or a failed update.
You must enable CIM OEM providers on the VMware ESXi 4 system after installing the Dell OpenManage bundle to manage a system with Dell OpenManage Server Administrator.
Using vSphere Client to Enable CIM OEM Providers:
To enable CIM OEM providers using VMware vSphere Client, you need to have the vSphere Client tool installed. You can download and install the tool from https://
To enable CIM OEM providers on the VMware ESXi 4 system using vSphere Client:
1) Log on to the VMware ESXi 4 system in which vSphere Client is installed.
2) Click the Configuration tab.
3) Under the Software section on the left side, click Advanced Settings.
4) In the Advanced Settings dialog box, click “UserVars” on the left pane.
5) Change the value of the “CIMOEMProvidersEnabled” field to 1.
6) Click OK.
7) Restart your system for the change to take effect. Use the Summary tab in vSphere Client to restart the system.
Saturday, November 21, 2009
Monday, November 16, 2009
Wednesday, November 11, 2009
vCenter and MSSQL
If you are using SQL 2008, make sure you go to the “CMD” line and change the default ODBC from 32 to 64 Bit
Should read: If you are using Windows 2008 64 bit OS and vCenter with SQL, launch the 32 bit ODBC connector.
Create a 32-Bit DSN on a 64-Bit Operating System
You can install or upgrade to vCenter Server on both 32-bit and 64-bit operating systems.
Even though vCenter Server is supported on 64-bit operating systems, the vCenter Server system must have
a 32-bit DSN. This requirement applies to all supported databases. By default, any DSN created on a 64-bit
system is 64 bit.
Procedure
1 Install the ODBC drivers.
n For Microsoft SQL Server database servers, install the 64-bit database ODBC drivers on your Microsoft
Windows system. When you install the 64-bit drivers, the 32-bit drivers are installed automatically.
n For Oracle database servers, install the 32-bit database ODBC drivers on your Microsoft Windows
system.
NOTE The default install location on 64-bit operating systems is C:\VMware.
2 Run the 32-bit ODBC Administrator application, located at [WindowsDir]\SysWOW64\odbcad32.exe.
3 Use the application to create your DSN.
You now have a DSN that is compatible with vCenter Server. When the vCenter Server installer prompts you
for a DSN, select the 32-bit DSN.
Tuesday, November 10, 2009
vSphere 4 Default and CTRL-ALT-DEL
To disable this yourself:
1. Edit /etc/inittab. Any text editors will do- I like nano but vi works just as well.
2. Search for "CTRL-ALT-DELETE" or "ctrlaltdel"
3. Comment out the line "ca::ctrlaltdel:/sbin/shutdown -t3 -r now" with a # symbol.It should look like:# Trap CTRL-ALT-DELETE
# ca::ctrlaltdel:/sbin/shutdown -t3 -r now
4. Save and exit the file.
5. To make this take effect without a reboot, run the command:
init q
Friday, November 06, 2009
Wednesday, October 28, 2009
Tuesday, October 27, 2009
VMware vSwitch and Cisco switch configuration
Standard trunk port Best Practice switchport configuration:
interface GigabitEthernet#/#
description <<** ESX Host #/# **>>
switchport trunk encapsulation dot1q
switchport trunk allowed vlan 1,#,#,#
switchport mode trunk
switchport nonegotiate
spanning-tree portfast trunk
exit
Standard ether-channel Best Practice switchport configuration:
IMPORTANT NOTE: Etherchannel is only applicable if all the interfaces bound to the channel are going to the same physical switch OR that all of the interfaces are going to different physical switches which are stacked together (with an actual stacking cable, not an ISL.) If you are running these interfaces to two separate network switches, you cannot Etherchannel them and they should be configured as above rather than the example below.
interface port-channel #
description <<** ESX EC# **>>
switchport
switchport trunk encapsulation dot1q
switchport trunk allowed vlan 1,#,#,#
switchport mode trunk
interface GigabitEthernet#/#
description <<** EC#/INT# **>>
switchport trunk encapsulation dot1q
switchport trunk allowed vlan 1,#,#,#
switchport mode trunk
channel-group # mode on
interface GigabitEthernet#/#
description <<** EC#/INT# **>>
switchport trunk encapsulation dot1q
switchport trunk allowed vlan 1,#,#,#
switchport mode trunk
channel-group # mode on
exit
NOTE: It is also worth mentioning that it is assumed the member ports (those with channel-group # mode on as above) will inherit their configuration from the channel-group but it is sometimes necessary to replicate that configuration to their individual switchport configurations as above.
Tuesday, October 20, 2009
Monday, October 19, 2009
FreeBSD and multiple gateways
Question: How to add multiple gateways to a FreeBSD?
Answer: No you can not do this (at least directly) on FreeBSD. FreeBSD don't support multiple gateways.
Workaround solution: If you have a server with 2 set of IPs and each set have there own gateway.
- First, you must select one of the gateway to be a default gateway.
- Then, You need ipfw (or any FreeBSD firewall solution),
Check that your kernel support ipfw, if not, recompile your kernel with the following options(IPDIVERT and DUMMYNET is not required, but if you add IPFW/IPFW2 it better to also add these two options)#Firewall & NAT & DummyNet
add the following rule to your ipfw rules set.
options IPFIREWALL
options IPDIVERT
options IPFIREWALL_DEFAULT_TO_ACCEPT
options IPFIREWALL_VERBOSE
options IPFIREWALL_VERBOSE_LIMIT=100
options DUMMYNET
options IPFW2ipfw add rule_no fwd second_gateyway_ip ip from ip_of_this_gateway to not me
For example, I have 2 ip set (10.0.0.100,10.0.0.101,10.0.0.102 for gateway 10.0.0.254) and (192.168.0.77,192.168.0.78 for gateways 192.168.0.254). I chose 10.0.0.254 as the default gateway. So, my ipfw rules areipfw add 100 fwd 192.168.0.254 ip from 192.168.0.77 to not me
ipfw add 110 fwd 192.168.0.254 ip from 192.168.0.78 to not me
Thursday, October 08, 2009
Články o administraci CISCO switchů
Článek o konfiguraci CISCO a ESX teamingu
http://www.samuraj-cz.com/clanek/vmware-esxi-a-nic-teaming-aneb-pripojeni-pres-vice-sitovek/
Thursday, September 24, 2009
Configure BIND DNS to Answer Active Directory Queries
http://www.linuxquestions.org/linux/answers/Networking/Configure_BIND_DNS_to_Answer_Active_Directory_Queries
Quick Setup:
If you have an Address Record (A) that identifies your server name like this:
dc1.example.com. A 111.222.333.444
Then your SRV records for this DC would be as follows
_ldap._tcp.example.com. SRV 0 0 389 dc1.example.com.
_kerberos._tcp.example.com. SRV 0 0 88 dc1.example.com.
_ldap._tcp.dc._msdcs.example.com. SRV 0 0 389 dc1.example.com.
_kerberos._tcp.dc._msdcs.example.com. SRV 0 0 88 dc1.example.com.
Tuesday, September 01, 2009
HA “Deepdive”
Article clearly explains:
- Primary and Secondary nodes
- Isolation Response
- Slot sizes/Admission Control
- Advanced settings
Monday, August 24, 2009
Sunday, August 16, 2009
DELL PowerConnect technical documents
http://www.dell.com/content/topics/global.aspx/solutions/en/pwcnt_papers?c=us&cs=555&l=en&s=biz
Sunday, July 19, 2009
Thursday, July 09, 2009
Infrastructure MS Visio Stnecils
http://www.visiocafe.com/
DELL Infrastructure MS Visio Stencils
http://www.visiocafe.com/dell.htm
Wednesday, July 08, 2009
Friday, July 03, 2009
Virtualization Performance Benchmark
Public results are available at http://www.vmware.com/products/vmmark/results.html
Thursday, July 02, 2009
A “Multivendor Post” to help our mutual iSCSI customers using VMware
http://virtualgeek.typepad.com/virtual_geek/2009/01/a-multivendor-post-to-help-our-mutual-iscsi-customers-using-vmware.html
Platespin Recon 3.6 - bugs and issues
MS Windows Virtual Memory Management on consolidated virtual workloads
Articles about this topic:
http://www.techarp.com/showarticle.aspx?artno=143
http://www.petri.co.il/pagefile_optimization.htm
http://www.instantfundas.com/2008/07/disable-windows-page-file-save-your.html
http://www.windowsdevcenter.com/pub/a/windows/2004/04/27/pagefile.html
http://smallvoid.com/article/windows-page-file.html
Saturday, June 27, 2009
Friday, June 26, 2009
Howto use VMware esxtop
Nice article http://www.hypervizor.com/2009/06/interactive-replay-batch-esxtop-modes/
Wednesday, June 24, 2009
Tuesday, June 23, 2009
PERL Getopt and GetOptions
See full article at http://aplawrence.com/Unix/perlgetopts.html
Ultimate Deployment Appliance
Thursday, May 14, 2009
How to shutdown windows from linux
Wednesday, May 13, 2009
Saturday, May 09, 2009
How to copy (backup) files from ESX3i?
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
Tuesday, March 31, 2009
Saturday, March 14, 2009
On demand VNC server with GDM
First of all you have to define new service in particular port. Add line bellow into /etc/services
vnc1024 5901/tcp # VNC & GDMnow create service description for xinetd. Go to directory /etc/xinetd.d
cd /etc/xinetd.dand create file vnc1024
service vnc1024Move to runlevel 3
{
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
}
init 3Restart xinetd
/etc/init.d/xinetdMove back to runlevel 5
init 5And that's it. Now try connect via VNCviewer to port 6901
Wednesday, February 18, 2009
DR & BC of virtualized datacenters
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
Tuesday, February 17, 2009
Configuration Point-to-Point OpenVPN link
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.
Sunday, February 15, 2009
Scripting reference manuals
http://www.ss64.com/index.html
Friday, January 30, 2009
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'.
Thursday, January 08, 2009
Tuesday, January 06, 2009
Monday, January 05, 2009
Tuesday, December 23, 2008
Top 10 PowerShell scripts that VMware administrators should use
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
Tuesday, December 09, 2008
iSCSI on FreeBSD
http://www.cyberciti.biz/faq/freebsd-iscsi-initiator-howto/
FreeBSD network link agregation
http://www.freebsd.org/doc/en/books/handbook/network-aggregation.html
Thursday, November 27, 2008
Friday, November 21, 2008
ESX Server, IP Storage, and Jumbo Frames
http://blog.scottlowe.org/2008/04/22/esx-server-ip-storage-and-jumbo-frames/
Note: even it's not supported solution yet
Saturday, October 11, 2008
UBNT Wispstation - default config
Default IP | 192.168.1.20 |
---|---|
Default name | ubnt |
Default password | ubnt |
Friday, October 10, 2008
System Information for Windows
http://www.gtopala.com/
This tool is extremely useful when you need to get your activation code from already installed Windows OS. When this tool does not work you can try KeyFinder
http://magicaljellybean.com/keyfinder/
Wednesday, October 01, 2008
New VMware technologies are comming ...
VMware FT (Fault Tolerance)
http://download3.vmware.com/vdcos/demos/FT_Demo_800x600.html
VMWare Distributed Virtual Switch
http://download3.vmware.com/vdcos/demos/DVS_Demo_800x600.html
Host Profiles
http://download3.vmware.com/vdcos/demos/Hostprofiles_Linked_VC_800x600.html
Storage vMotion (GUI)
http://download3.vmware.com/vdcos/demos/Storage_VMotion_800x600.html
Citrix XenServer & EqualLogic Storage Integration
Sunday, August 24, 2008
How to crimp RJ45 connector?

Nice article with more information is at http://www.ertyu.org/steven_nikkel/ethernetcables.html
Thursday, July 24, 2008
VirusTotal
Tuesday, July 08, 2008
Wednesday, June 25, 2008
Understanding and fixing VMware ESX problems without pulling the plug
Understanding and fixing VMware ESX problems without pulling the plug
Eric Siebert, Contributor
06.24.2008
LINK TO ARTICLE
Wednesday, June 04, 2008
VMware: configuring a static MAC address in a VM
Sometimes it can be necessary to configure a static MAC address in a VM. A typical issue during P2V is an application that has its licensing based on the MAC address.
VMware has defined that VirtualCenter does not use the following range: 00:50:56:00:00:00 to 00:50:56:3F:FF:FF where 00:50:56 is the OUI.
The steps:
1. Power off & remove the server from the VirtualCenter inventory. This is a necessary step, because VC will overwrite your settings during Power On!
2. Edit the .vmx file and locate the following generated MAC address:
Ethernet0.addressType =
and
Ethernet0.generatedAddress =
3. Change the value for ethernet0.addressType from “vpx” to “static”
4. Change ethernet0.GeneratedAddress to ethernet0.Address
5. Change the current MAC to a MAC address in the following range:
00:50:56:00:00:00-00:50:56:3F:FF:FF
6. In VirtualCenter, select an ESX host and go to storage
7. Browse the data store & locate your VM
8. Right-click on the .vmx file, and select Add to inventory
9. Power On the server. Issue the command ipconfig /all and locate the VMware NIC. Your manually assigned MAC address should be there.
I know you can set your MAC address inside Windows, but I would avoid this.
Tuesday, June 03, 2008
Monday, June 02, 2008
DELL Professional Services aneb GICS
http://davidpasek.blogspot.com/2006/06/dell-jak-ho-mon-neznte.html
Presne 15.5.2008 jsem se stal clenem byvaleho DPS - DELL Professional Services, ktere se dnes jmenuje GICS - Global Infrastructure Consulting Services. Moje zamereni je primarne na serverovou konsolidaci a virtualizaci, nicmene jelikoz jsem zatim prvni Solution Architect DELLu v Ceske Republice, tak mam na starosti i enterprise storage a networking.
Wednesday, April 16, 2008
Friday, March 21, 2008
ESX Server, NIC Teaming, and VLAN Trunking
...
There are actually two different pieces described in this article. The first is NIC teaming, in which we logically bind together multiple physical NICs for increased throughput and increased fault tolerance. The second is VLAN trunking, in which we configure the physical switch to pass VLAN traffic directly to ESX Server, which will then distribute the traffic according to the port groups and VLAN IDs configured on the server. I wrote about ESX and VLAN trunking a long time ago and ran into some issues then; here I’ll describe how to work around the issues I ran into at that time.
...
Full article:
http://blog.scottlowe.org/2006/12/04/esx-server-nic-teaming-and-vlan-trunking
Other useful technical paper about VLAN on ESX is at
http://www.vmware.com/resources/techresources/412
Monday, March 17, 2008
Friday, March 14, 2008
How to Set up VNC on Debian GNU/Linux
Installation and usage
You've just installed Debian, but your wife wants her monitor back. That's OK, you were planning on running it headless, anyway. But, wouldn't it be nice to check out some of those groovy GUI apps? Don't fret, VNC will let you interact with a desktop environment from just about any platform available.
Install vncserver (as root): apt-get install vncserver
Choose your desired window size and color depth, then, as an ordinary user, open a terminal and type:vncserver -geometry 1024x768 -depth 24
orvncserver -geometry 1024x768 -depth 24 -pixelformat rgb565
This will prompt you to create a password:
You will require a password to access your desktops.
Password:
Verify
The server will start and tell you where to access it:
New 'X' desktop is foobar:1
Starting applications specified in /etc/X11/Xsession
Log file is /home/jorey/.vnc/foobar:1.log
Open the VNC viewer on your remote machine, enter the hostname:screen and password (use a hostname or IP that your client machine understands), and your Linux desktop will open in a window! Network speed and processor power will affect performance, but it's amazing how many apps will run fine under VNC. You might not be able to play Frozen Bubble, but you can use productivity applications without any trouble.
To kill the server enter a command similar to this, using the appropriate settings:vncserver -kill :1
The reason for killing the session is that you may need to edit the default configuration file that vncserver
creates for you, for example to get the vncserver to run the K desktop environment instead of twm
, you may want to edit the $HOME/.vnc/xstartup
file to replace the line:
twm &
with this line is you use KDE:
startkde &
and with this line if you use GNOME:
gnome-session &
before launching the vncserver again using:
vncserver :1 -geometry 1024x768 -depth 16 -pixelformat rgb565
VNC over OpenSSH
The following is just a summary of the full explanation. To use VNC over OpenSSH, first you need to run an
ssh
session on the machine where you will be running the vncviewer, to request that ssh
listen on a particular port on your local machine, and forward communication on that port down the secure connection to a port on the machine running the vncserver.
For example:
ssh -L x:localhost:y vncserver_machine
means "Start an SSH connection to the vncserver_machine
, and also listen on port x
on my machine, and forward any connections there to port y
on the vncserver_machine
."
Now, the VNC protocol normally uses port 59xx
, where xx
is the display number of the server. So a VNC server on a Windows machine, which normally uses display number 0
, will listen on port 5900
. The first VNC server on linux will probably use display number 1
, and subsequent servers would use 2
, 3
, etc. and so the vncservers on linux will be listening on ports 5901
, 5902
and so forth. By forwarding these ports to a remote machine running vncserver
, you can make the remote VNC server appear to be a server running on your local machine. So, imagine you had a VNC server running as display :1
on vncserver_machine
, and you wanted a secure connection to it from your local machine. You could start the ssh
session using:
ssh -CL 5902:localhost:5901 vncserver_machine
After that, starting up the vncviewer
as follows on your local machine: vncviewer -encodings "copyrect hextile" localhost:2 would actually connect to display :1
on the vncserver_machine
.
Note that the above OpenSSH command-line is deliberately meant to accept incoming connections only from the local machine. This means that to use the ssh
connection that we have just set up, we must connect to it from the same machine, using the special name localhost
, rather than using the local machine's own unique name.
This article is compiled from following resources:
http://www.joreybump.com/code/howto/debian/vnc.html
http://www.penlug.org/twiki/bin/view/Main/TightVNC
X Window Servers
http://mediakey.dk/~cc/x11-for-windows-xp-and-vista/
X Ming "X Server"
http://www.straightrunning.com/XmingNotes/
"X Server" for Mac OS X
http://www.apple.com/downloads/macosx/apple/
macosx_updates/x11formacosx.html