제2의 비엔지니어 인생관을 꿈꾸며

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Unable to add esxi host to vcenter Datacenter.QueryConnectionInfo
사용자 삽입 이미지
Cannot contact the specified host. The host may not be available on the network, a network configuration problem may exist, or the management service on this host is not responding
There are lots of actions you need to follow. In my case non of those action resolved my issue except one step no#5
Here are the quick steps you need to follow to find out why you are having Datacenter.QueryConnectionInfo error message while adding host to vcenter.
  1. Lockdown mode is enabled on the ESXi host
  2. Incorrect credentials are entered when adding the ESXi host.
  3. Try full fqdn and add again.
  4. Check DNS settings on vcenter and ESXi host
  5. Your vcenter does not support the ESXi host build number. This issue started to appear after recent upgrade on Esxi 5.5 servers. If your vcenter server is below  vCenter Server 5.5 Update 3b you cannot add host running ESXi 5.5 Update 3b. You need to upgrade your vCenter server to 5.5 U3b in order to add ESXi 5.5 U3b host.
ESXi Build number 3248547
vCenter Server 5.5 Update 3b Build No 3252642

필자는 5번째 이슈에 걸렸습니다. 똑같은 5.5 버젼인데 OS도 바꿔보고 지웠다 깔고 서비스 재시작하고 여러번을 반복해도 원인을 알수가 없었습니다.
구글에 검색해보니 5.5 버젼에서만 Update 빌드버젼이 다르면 호스트 추가 오류가 발생 한다는걸 알게되었습니다. 벰웨어도 잠깐 공부좀 해볼까 해서 설치하는데 이런데서 막히니까 그냥 포기할려다가 해결된 케이스였습니다. Hyper-V 에만 손에 익숙해서인지 보통 벰웨어가  구축 및 설정이 더 편하다고 인식되었는데 그냥 복불복 아닌가 생각이 들고 있습니다.
2016/03/06 22:54 2016/03/06 22:54
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http://social.technet.microsoft.com/wi ··· 016.aspx

OpenGL API support (up to OpenGL 4.4)
  • OpenCL API Support (up to OpenCL 1.1)
  • Expanded the amount of dedicated vRAM assignable to a VM to 1GB
  • Decoupled vRAM from Monitors and Resolution
  • Example applications: Adobe Photoshop CS, ArcGIS Pro, Solidworks, etc.
  • Added support for RemoteFX vGPU when running Server VMs as a VDI guest
  • Added support for Generation 2 VMs
  • Improved end to end user experience
    • Higher Render FPS and lower Jitter
    • Improved application compatibility
일단 위내용데로 지원범위가 넓어졌고 그래픽 가상화 부드러움의 선두주자 젠앞에서는 RemoteFX는 명함도 못내밀 정도였습니다. 특히 캐드 사용자들의 불만이 가장 높았고 일부 프로그램에서는 3D가속지원이 되지 않는다고 기능이 추가되도 전혀 사용도 하지 못하는 사례가 많은 MS 가상화였습니다. 이제까지 서버 가상화에서만 쓸만한 제품이 아니라 VDI 시장에 많은 영향력을 발휘할거란게 필자의 판단입니다. 이제까지 MS가 뭐 지원한다고 떠들어도 막상 써보면 영 아닌데?라는 생각을 한게 한두번이 아니였습니다. 젠은 쓸만은 한데 이기능 저기능 쓸라면 라이센스 비용의 부담이 많고 여러가지 고민을 하게되는 그래픽 가상화의 장벽이였습니다.
그래서 필자가 Windows 10의 RemoteFX 가상화 한대를 올리고 테스트를 해봤습니다.

사용자 삽입 이미지
사용자 삽입 이미지
위그림과 같이 말많았던 오토캐드 성능 테스트와 포토샵까지 사용을 해봤습니다. 캐드가 상당히 부드럽게 돌아가는걸 느낀후 이제는 말할수 있다 RemoteFX편을 만들고 싶었습니다. 포토샵이야 2D를 주로 사용하는 프로그램이라 고만고만 하였지만 그림처럼 하드웨어 가속 활성화가 표기가 되어 있었습니다.

마지막으로 테스트를 Windows 10/Server 2016 이 아닌 Hyper-V Server 2016 Core Free 버젼으로 테스트를 진행할 계획입니다.
2015/12/28 22:00 2015/12/28 22:00
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If you want to be the best at something you gotta start somewhere, get stuck somewhere & find your way out.

Today I am going to show you how to remove Exchange Server from a network when you are unable to uninstall it / You have created a new server & want to get rid of the old server but it wont go away easily.

Word of Warning!

Now I am doing this on VMware Workstation Test Lab and you will have to be very very careful and double check what you are doing before you do it if you are on a production environment , because deleting something from any of these steps will cause serious network & server instability if not done correctly. The recommended way to remove an Exchange server from your network is to properly uninstall it. If the installation no longer exists, then there is also the option of installing a new server with the same name and restoring the original Exchange configuration. However, I have not explored this path as it appears to be much more time consuming.

If you removed an Exchange 2007/2010/2013 server from your network without properly uninstalling it, either because you experimented with it on a test box or on a virtual machine, or because the computer got hit by an earthquake, or simply because you didn’t know better, you may notice that the server continues to exist in the network’s Active Directory and shows up in the Exchange Management Console of your new exchange server.

This Post will help you clean those aftermath in your domain controller without having to reinstall your entire Infrastructure.

Removing AD Configuration

The list of Exchange servers on the domain is stored in the Active Directory configuration. Following steps below to remove the obsolete server:

1. Log on to the Domain Controller.

2. From the Start menu select Run and enter adsiedit.msc to launch the ADSI Edit tool

3. In the tool, right-click ADSI Edit and select Connect To…

4. In the Connection Settings dialog under Select a well known Naming Context select Configuration and click OK

5. Navigate to CN=Configuration [domain] → CN=Services → CN=Microsoft Exchange → CN=[organization] → CN=Administrative Groups → CN=Servers

6. Right-click and Delete the container for the offending Exchange server.

Removing Mailboxes

The Active Directory also stores information about the mailboxes that were located on the non-existent server. To remove these, perform the following steps in the ADSI Edit tool:

1. Navigate to CN=Configuration [domain] → CN=Services → CN=Microsoft Exchange → CN=[organization] → CN=Administrative Groups → CN=Databases

2. Identify the Mailbox Database containers that belonged to the lost server and Delete them.

Make sure that you are not deleting working mailboxes from the list, if you delete any by mistake you will have to delete & recreate the entire user using Active Directory Users & Computers. If there are multiple Exchange servers on the network, the Mailbox Database folders to delete can easily be identified by clicking on the folder and checking the Name field of the first entry, which should contain the name of the lost computer. Do not delete references to databases belonging to other Exchange servers!

Removing Security Settings

Now that the server is removed, some other settings need to be cleaned up as well. Perform the following additional steps on the domain controller:

1. Launch Server Manager

2. Navigate to Roles → Active Directory Domain Services → Active Directory Users and Computers [domain] → [domain] → Microsoft Exchange Security Groups

3. Remove the computer from the members list of Exchange Servers

4. Remove the computer from the members list of Exchange Trusted Subsystem.

If the computer was removed from the network altogether, you may also want to remove it from the Active Directory’s list of computers, as well as the DNS Server’s Forward Lookup Zones.

Please note that the above steps will work for Exchange 2007 / 2010 & 2013

2015/12/07 11:09 2015/12/07 11:09
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업그레이드가 되어서 플러그인이나 액티브X가 안되어 전사적으로 문제가 될수 있기에 정책으로 내려버리는 방법도 있습니다.

2015/07/27 11:02 2015/07/27 11:02
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 — Create New Virtual Host Files

Virtual host files are the files that specify the actual configuration of our virtual hosts and dictate how the Apache web server will respond to various domain requests.

Apache comes with a default virtual host file called 000-default.conf that we can use as a jumping off point. We are going to copy it over to create a virtual host file for each of our domains.

We will start with one domain, configure it, copy it for our second domain, and then make the few further adjustments needed. The default Ubuntu configuration requires that each virtual host file end in .conf.

Create the First Virtual Host File

Start by copying the file for the first domain:
sudo cp /etc/apache2/sites-available/000-default.conf /etc/apache2/sites-available/yourdomain.com.conf

Open the new file in your editor with root privileges:
sudo nano /etc/apache2/sites-available/yourdomain.com.conf

The file will look something like this (I've removed the comments here to make the file more approachable):
<VirtualHost *:80>
    ServerAdmin webmaster@localhost
    DocumentRoot /var/www/html
    ErrorLog ${APACHE_LOG_DIR}/error.log
    CustomLog ${APACHE_LOG_DIR}/access.log combined

As you can see, there's not much here. We will customize the items here for our first domain and add some additional directives. This virtual host section matches any requests that are made on port 80, the default HTTP port.

First, we need to change the ServerAdmin directive to an email that the site administrator can receive emails through.
ServerAdmin admin@yourdomain.com

After this, we need to add two directives. The first, called ServerName, establishes the base domain that should match for this virtual host definition. This will most likely be your domain. The second, called ServerAlias, defines further names that should match as if they were the base name. This is useful for matching hosts you defined, like www:
ServerName yourdomain.com
ServerAlias www.yourdomain.com

The only other thing we need to change for a basic virtual host file is the location of the document root for this domain. We already created the directory we need, so we just need to alter the DocumentRoot directive to reflect the directory we created:
DocumentRoot /var/www/yourdomain.com/public_html

In total, our virtualhost file should look like this:
<VirtualHost *:80>
    ServerAdmin admin@yourdomain.com
    ServerName yourdomain.com
    ServerAlias www.yourdomain.com
    DocumentRoot /var/www/yourdomain.com/public_html
    ErrorLog ${APACHE_LOG_DIR}/error.log
    CustomLog ${APACHE_LOG_DIR}/access.log combined

Save and close the file.

Copy First Virtual Host and Customize for Second Domain

Now that we have our first virtual host file established, we can create our second one by copying that file and adjusting it as needed.

Start by copying it:
sudo cp /etc/apache2/sites-available/yourdomain.com.conf /etc/apache2/sites-available/test.com.conf

Open the new file with root privileges in your editor:
sudo nano /etc/apache2/sites-available/test.com.conf

You now need to modify all of the pieces of information to reference your second domain. When you are finished, it may look something like this:
<VirtualHost *:80>
    ServerAdmin admin@test.com
    ServerName test.com
    ServerAlias www.test.com
    DocumentRoot /var/www/test.com/public_html
    ErrorLog ${APACHE_LOG_DIR}/error.log
    CustomLog ${APACHE_LOG_DIR}/access.log combined

Save and close the file when you are finished.

 — Enable the New Virtual Host Files

Now that we have created our virtual host files, we must enable them. Apache includes some tools that allow us to do this.

We can use the a2ensite tool to enable each of our sites like this:
sudo a2ensite yourdomain.com.conf
sudo a2ensite test.com.conf

When you are finished, you need to restart Apache to make these changes take effect:
sudo service apache2 restart

You will most likely receive a message saying something similar to:
 * Restarting web server apache2
 AH00558: apache2: Could not reliably determine the server's fully qualified domain name, using Set the 'ServerName' directive globally to suppress this message

This is a harmless message that does not affect our site.

— Set Up Local Hosts File (Optional)

If you haven't been using actual domain names that you own to test this procedure and have been using some example domains instead, you can at least test the functionality of this process by temporarily modifying the hosts file on your local computer.

This will intercept any requests for the domains that you configured and point them to your VPS server, just as the DNS system would do if you were using registered domains. This will only work from your computer though, and is simply useful for testing purposes.

Make sure you are operating on your local computer for these steps and not your VPS server. You will need to know the computer's administrative password or otherwise be a member of the administrative group.

If you are on a Mac or Linux computer, edit your local file with administrative privileges by typing:
sudo nano /etc/hosts

If you are on a Windows machine, you can find instructions on altering your hosts file here.

The details that you need to add are the public IP address of your VPS server followed by the domain you want to use to reach that VPS.

For the domains that I used in this guide, assuming that my VPS IP address is, I could add the following lines to the bottom of my hosts file:   localhost   guest-desktop yourdomain.com test.com

This will direct any requests for yourdomain.com and test.com on our computer and send them to our server at This is what we want if we are not actually the owners of these domains in order to test our virtual hosts.

Save and close the file.

To remove the host file just delete it.

If you just want to dissable the site, use

sudo a2dissite sitename

Restart apache2

sudo /etc/init.d/apache2 reload

Again to remove (delete)it completely from the system,

sudo rm /etc/apache2/sites-available/sitename


2015/07/16 14:22 2015/07/16 14:22