Frequently Asked Questions

General Information

What rights do I have on the machine?

On a Windows environment you have administrative rights.

On a Realm Unix/Linux lab machine you have the same rights as you have in the computer labs.

On a Linux environment you have administrative rights.

Some images are specifically configured not to allow users to have administrative rights.

How do I make a VCL Reservation?
  1. Click the Reservations link at the top of the page
  2. If you are not already authenticated, you will be presented with a login screen. Select your affiliation and proceed to login.
  3. Click the New Reservation button
  4. Based on you level of access, you will be presented with a menu of VCL application environments to choose from.
  5. Select the VCL application environment you would like to use.
  6. Select the time you would like to start the reservation, for an immediate session select ‘Now’.
  7. Select the duration of your reservation, by default the initial duration is 1 hour. Once the reservation is active it can be extended to a total of 6 hours. Under special cases longer durations are available.
  8. Submit your request.
  9. The page will update to display your reservation. You will see a pending signal while the assigned compute node is being prepared. Click on the ‘Pending…’ link for details of the processing.
  10. Once ready, a ‘Connect’ button will appear. Depending on the environment, it can take anywhere from 1 to 20 minutes for the request to be ready.
  11. After hitting the Connect button, you we see the details of your requested environment. The details can include the remote IP address, a single one-time password (depending on the environment) and information on how to connect to the remote computer running the application environment you selected.  Also note that the details regarding the connect information will change for each reservation you make.
  12. Connect to the remote machine.
I clicked “Remember my selection” on the page where I select an authentication method.  How do I change it?

The following URL will allow you to change your selection:
https://vcl.ncsu.edu/scheduling/index.php?mode=selectauth&clearselection=1

My reservation timed out. What does this mean?

If you have disconnected or logged out of your assigned machine. You will have up to 15 minutes to reconnect before the system assumes you have left the reservation. Once 15 minutes has been reached, the VCL system times out your reservation and will start the reclaim process. The reclaim process involves reinstalling the machine and you will loose any work you have left on the remote machines’s hard drive.

Make use of any network drives at all times to make sure you don’t loose any work.

Note: Server reservations or reservations greater than 24 hours are excluded from this timeout.

VCL Reservations

Can I reconnect to a computer if my reservation time has not expired but I disconnected?

Yes. Just run Remote Desktop Connection or SSH again and login with the same user name and password. You will have 15 minutes to reconnect, before your reservation is timed out.

Reconnecting to a Remote Desktop session on a Windows server will show you to the “desktop” you were already using, with all of the programs and files you had open. Whereas reconnecting to a SSH session on a UNIX or Linux server will be like logging in initially, any programs you had running previously will no longer be running.

What rights do I have on the VCL machine?

On custom Windows and Linux environments you have administrative and root level rights. Since the VCL system reloads each expired reservation with a clean environment, there is no threat of any residual data being left on a machine for the next user. However, some images have administrative level access specifically disabled.

On Linux Lab machine environments, you only have user level rights. The same permissions as you would experience at the console of a walk-in lab.

How to print from a remote VCL computer?

Printing within VCL can be difficult due to the number of different printers that exist. Some printers that are locally attached through Remote Desktop Connection will be recognized by the default Windows printer drivers, others printers will not. To work around this, most VCL windows environments should have pdfFactory installed. PdfFactory will show up as a virtual printer and is selectable as a printer within the windows applications. This will print the output to a pdf and then you can copy this pdf file to your machine and print as you normally do.

If your local printer is not supported by the default windows drivers, then you must select the pdfFactory and print to a pdf file.

Modifying Reservations

I need more time than I originally thought.  How can I get it?

On the website:

  • Click Reservations
  • Find your reservation, and click the ‘Edit’ button
  • Find the drop-down box that has a time in it, and change it to a longer time
  • Click ‘Confirm Changes’.

You will only be able to extend the length if the computer your reservation is on has time available before the next reservation. The maximum time for a reservation (even with an extension) is typically 8 hours from the initial starting time of your reservation.

Deleting Reservations

What happens at the end of my reservation?

You will receive warnings at 10 minutes and 5 minutes before your reservation expires.  Once time is up, you are disconnected and any unsaved changes you have made will not be recoverable.

Reservation Notifications

I do not receive emails confirming my reservations

Email notification can be enabled/disabled under User Preferences->General Preferences.

If email notification is enabled and you are not receiving emails, it is likely because the email address that the confirmation/notification emails are being sent to is not the email address that you primarily use. The email address that all VCL emails are sent to is the one listed in the NCSU online directory.

To change what email address VCL related emails are sent to, look yourself up in the NCSU online directory and follow the information provided there on updating your information.

Connecting to VCL

How long do I have to wait after I hit ‘Connect’ before I can login into my reserved machine?

During periods of heavy utilization, it may take a minute before the time you hit ‘Connect’ and when you can actually connect; however, it will normally be ready by the time you try to connect to the computer.

What are the system requirements for connecting?

Windows

  • To connect to another Windows computer, you need a Remote Desktop Connection application:
    • Microsoft’s Remote Desktop Connection is installed by default on Windows OS
  • Ericom Blaze client

Google chrome also has various remote desktop Apps – some work better than others.

  • To connect to a Unix/Linux computer you must have an SSH client (such as PuTTY). To display graphical applications you will also need an X server (such as X-Win32).

Macintosh

  • To connect to a Windows computer you will need a Remote Desktop Connection application:
    • Microsoft’s Remote Desktop Connection software is available via the Apple App Store
  • Ericom Blaze client
  • To connect to a Unix/Linux computer you will need:
    • ssh command is accessed through the Temerinal application
  • X11 if running applications remotely

Linux

  • Linux includes a Remote Desktop client (xfreerdp), as well as SSH/X.
Can I reconnect to a computer if my reservation time has not expired but I disconnected?

Yes. Just run Remote Desktop Connection or SSH again and login with the same user name and password. You will have 15 minutes to reconnect, before your reservation is timed out.

Reconnecting to a Remote Desktop session on a Windows server will show you to the “desktop” you were already using, with all of the programs and files you had open. Whereas reconnecting to a SSH session on a UNIX or Linux server will be like logging in initially, any programs you had running previously will no longer be running.

How do I connect  to a VCL environment from a Macintosh?

Depending on the VCL environment, you will need to use a remote desktop connection or ssh (secure shell) client.  Remote desktop connection can be freely downloaded from Mac App Store.   An ssh (secure shell) client is natively available in Mac OS X.  Open a terminal window and use the command ssh.

How do I connect to a VCL environment using a Linux machine?

Depending on the environment you will need to use a remote desktop connection client or a ssh client. The ssh (secure shell) client is native to the linux operating system, open a terminal window and use the command ‘ssh’.

The remote desktop client ‘rdesktop’ for Linux/Unix operating systems is a third party application downloaded from sourceforge: http://sourceforge.net/projects/rdesktop/. Depending on your distro, rdesktop may already be installed – open a terminal window and try to run the command rdesktop.

A full list of options are documented in rdesktop man page, but a sample command line might look like the following:

  • rdesktop -g 1024×768 -a 24 -r disk:home=/home/<userid> -r disk:root=/ -r printer:<localqueue>

There is a nice GTK frontend called tsclient for rdesktop. It is likely available on your distro as well.  If not, it can be dlownloaded from sourceforge as well: http://sourceforge.net/projects/tsclient

If accessing a windows VCL resource from NCSU campus Linux and Solaris lab machines, rdesktop is available through the netutils locker. Run the command ‘add netutils’ in a terminal window to access the rdesktop command.

Usernames and Passwords

I logged out and forgot my password.  How do I look it up?

Revisit the VCL website:

  • Click on Current Reservations
  • Click on “Connect” button

Your connection details will be displayed.

Remote Desktop

How do I modify my remote desktop connection screen size when using the Get RDP file?

On the website:

  • Click ‘Reservation System’ in the left pane
  • Select the User Preferences link in the left pane
  • Select the RDP file preferences

Here you can edit the default settings for your RDP file for the screen size resolution, local drives, and sound.

What is an RDP file?

An RDP file is a settings file that can be opened by the Remote Desktop Client to automatically open a connection to the reserved computer.

For automatic login, provided your browser and operating system properly support the auto login feature. The RDP file can be used to automatically login you into the remote machine, just by simply clicking the Get RDP file button.

When I click Get RDP file, Internet Explorer gives an error and states it cannot download index.php from vcl.ncsu.edu

This is related to a security setting in Internet Explorer which for some reason does not allow file downloads over a secure connection (https).

To fix this problem:

  1. Within Internet Explorer, click “Tools”
  2. Click “Internet Options”
  3. Select the “Advanced” tab
  4. Under the Security settings section make sure “Do not save encrypted pages to disk” is checked
  5. Click Apply
  6. Close the Internet Options window

Attempt to get the RDP file again: click “Get RDP file”.  You should be able to save the RDP file to your local computer and open it to access the remote VCL machine.

My VCL Windows Application crashed when saving files to my personal machine through Remote Desktop

Many applications read and write to files many times very quickly. When the file is on the same machine this is fine. Even if it is on the network, as long as there is a fast network connection, it will work, though with some degraded performance.

However, the process by which you gain access to files on your personal machine through Remote Desktop is quite complicated. Therefore, it will not be fast enough for some applications. In these cases, it is recommended that you copy your files to the VCL machine, work on you files there, and then copy them back to your personal computer when you are done with your work.

SSH

How do i  use ssh identity key authentication for Linux reservations?

For Faculty & Instructors

as an instructor, how do i request course access to vcl windows or linux environments?

Simply send a email request to vcl_help@ncsu.edu. Please state the course number section and the desired application environment for your course. All appilcations on the Linux and Solaris platforms are already available to NCSU students, staff and faculty.

The only requirement for access to custom environment is the course will need to be active in Wolfware.

how do i create a custom vcl environment?

This advanced feature is reserved for Faculty or support staff of a course such as a TA, system administrators for a College or Department, or researchers. The ability to create and or update VCL environments requires Image Creation privileges. Due to the storage limitations, Image creation privilege is not generally available and must be requested by Faculty or departmental systems administrator.

How to Create Windows Images.

How to Create Linux Images.

how do i update images?

Updating images (or environments) is similar to the Image Creation process. The owner of an image is the only one who can update a VCL environment.

Applications & Images

why aren’t there offices/productivity applications installed in each environment?

The purpose of each VCL environment is to provide someone access to an application or group of applications that the person wouldn’t have access to already. There are many Office/Productivity Suites available that can be installed on each user’s machine that will be used to connect to the VCL system. OpenOffice is available for free and is compatible with Microsoft Office.

Files & Data

what happens if i leave my work on the vcl machine?

Windows and Linux environments are reloaded after your reservation has completed or your session has timed out.  Therefore, any work left on the server is erased or lost.  Make sure you save your work to the network filespace (AFS), a thumb drive, or your local computers hard drive.

how do i transfer files between my computer and the remote one?

This depends on what operating system you are connecting from and to.  See ‘Where to save my files’ for a detailed explanation.

where should i save my failes when connecting to a non-realm red hat enterprise linux vcl environment?

Most of the non-Realm Linux environments have openAFS installed and configured for NCSU acounts. If you are using a NCSU account, simply transfer you data from the remote machine to a location in /afs.

If AFS or some other network share is not mounted. Then you will need to transfer your data using sftp(secure file transfer protocol) or scp(secure copy). This requires you to copy it to your local machine or another machhine you have access to.

Copying data from the remote computer to your local machine:

  • Windows – you will need an SCP client such as WinSCP
    • More information can be found at the EOS Remote Access site under WinSCP
  • Linux – simply use the native scp command
  • Mac OS X –
    • scp/sftp are native commands, open a terminal window. There is also a man page which provides more detailed information ‘man scp’ or ‘scp –help’
    • Fugu – A Mac OS X SCP and SFTP graphical frontend.
    • Cyberduck – A Mac OS X SFTP graphical frontend.

Traditional ftp (file transfer protocol) is not recommended. It does not support encyrption or secure authentication. Also, some locations actually block ftp network traffic.

where should i save my files when connecting to a realm red had enterprise linux vcl environment?

When connecting to a Realm Linux computer, your current working directory is your AFS home directory. So any data generated/modified will reside in your campus file space.

where should i save my files when connected to a windows reservation?

For remote access to a Windows VCL environment there are 3 options for saving your files:

  1. Local Hard Drive tunneled through the Remote Desktop session
  2. AFS Home Directory via the OpenAFS Client (K: drive)
  3. AFS Home Directory via SCP/SFTP client (F-Secure)

 

  1. Local Hard Drive tunneled through the Remote Desktop session: Before you connect to a Windows computer, click the ‘Options’ button in the Remote Desktop Connection window. Go to the ‘Local Resources’ tab, and check ‘Disk drives’ under the ‘Local Devices’ section. Then connect to the remote server. Once connected, under ‘My Computer’ on the remote server you will notice a drive that has the name of your computer and is mapped to your Local Hard Drive. This setting is enabled by default in the .RDP configuration files distributed at the ‘Connect!’ page that is displayed after making a reservation. That setting is one of many that can be configured in your VCL User Preferences.
  2. AFS Home Directory via the OpenAFS Client: The OpenAFS Client is installed on most of the Windows environments used in the VCL. This will be listed as the “K: drive” under my computer. If the K: drive does not exist, double click on the desktop icon labeled “Map AFS” and enter your campus username and unity password. See the AFS Space at NC State page for additional information on AFS.
  3. AFS Home Directory via SCP/SFTP client (WinSCP) WinSCP is installed in most of the Windows environments used in the VCL. WinSCP is an SCP/SFTP client made to securely transfer files. See the OIT WinSCP page for more information about WinSCP.

Note: DO NOT leave your work on the hard drive of Windows environments. What happens when I leave my work on the server?

VCL Website

when hitting forward in my browser in the scheduling interface, i keep getting the intitial page

This is often caused by using Back/Forward in certain web browsers (particularly Safari on Macintosh).

In order for the web application that is the scheduling interface for VCL to work correctly it must know what web page you were referred from when showing you any page except for the entry page. Some web browsers (Safari in particular) tend to forget exactly how you came to a given webpage. Thus when your web browser tries to load a given page in the scheduling interface and cannot remember how you can to be at that page, the scheduling web application sends you back to the entry page.

i click “remember my selection” on the page where i select an authentication method.  How do i change it?

The following URL will allow you to change your selection:
https://vcl.ncsu.edu/scheduling/index.php?mode=selectauth&clearselection=1

Common Problems

Application Problems

my vcl windows application crashes when saving files to my personal machine through remote desktop

Many applications read and write to files many times very quickly. When the file is on the same machine this is fine. Even if it is on the network, as long as there is a fast network connection, it will work, though with some degraded performance.

However, the process by which you gain access to files on your personal machine through Remote Desktop is quite complicated. Therefore, it will not be fast enough for some applications. In these cases, it is recommended that you copy your files to the VCL machine, work on you files there, and then copy them back to your personal computer when you are done with your work.

applications accessed via vcl are running very slowly

The technologies employed in VCL to provide applications remotely are fairly network intensive. It is recommended that a Cable/DSL connection be used.

Additionally, even in scenarios where Cable/DSL is provided by your Internet Service Provider, there can be connection/configuration issues that slow down your network connection to a crawl. Please run one of the Bandwidth Speed Tests to see how fast your connection is operating at the moment. Rates at or above 1Mbit are acceptable for Cable/DSL. If you are testing at or above 1Mbit and still having extreme slowness, contact VCL Support.

Performance Problems

My vcl windows application crashed when saving files to my personal machine through remote desktop

Many applications read and write to files many times very quickly. When the file is on the same machine this is fine. Even if it is on the network, as long as there is a fast network connection, it will work, though with some degraded performance.

However, the process by which you gain access to files on your personal machine through Remote Desktop is quite complicated. Therefore, it will not be fast enough for some applications. In these cases, it is recommended that you copy your files to the VCL machine, work on you files there, and then copy them back to your personal computer when you are done with your work.