This section provides an introduction to the SonicOS Enhanced SSL VPN NetExtender feature. This section contains the following subsections:
SonicWALL’s SSL VPN NetExtender feature is a transparent software application for Windows, Mac, and Linux users that enables remote users to securely connect to the remote network. With NetExtender, remote users can securely run any application on the remote network. Users can upload and download files, mount network drives, and access resources as if they were on the local network. The NetExtender connection uses a Point-to-Point Protocol (PPP) connection.
NetExtender provides remote users with full access to your protected internal network. The experience is virtually identical to that of using a traditional IPSec VPN client, but NetExtender does not require any manual client installation. Instead, the NetExtender Windows client is automatically installed on a remote user’s PC by an ActiveX control when using the Internet Explorer browser, or with the XPCOM plugin when using Firefox. On MacOS systems, supported browsers use Java controls to automatically install NetExtender from the Virtual Office portal. Linux systems can also install and use the NetExtender client.
After installation, NetExtender automatically launches and connects a virtual adapter for secure SSL-VPN point-to-point access to permitted hosts and subnets on the internal network.
The following sections describe advanced NetExtender concepts:
NetExtender is a browser-installed lightweight application that provides comprehensive remote access without requiring users to manually download and install the application. The first time a user launches NetExtender, the NetExtender stand-alone client is automatically installed on the user’s PC or Mac. The installer creates a profile based on the user’s login information. The installer window then closes and automatically launches NetExtender. If the user has a legacy version of NetExtender installed, the installer will first uninstall the old NetExtender and install the new version.
Once the NetExtender stand-alone client has been installed, Windows users can launch NetExtender from their PC’s Start > Programs menu and configure NetExtender to launch when Windows boots. Mac users can launch NetExtender from their system Applications folder, or drag the icon to the dock for quick access. On Linux systems, the installer creates a desktop shortcut in /usr/share/NetExtender. This can be dragged to the shortcut bar in environments like Gnome and KDE.
NetExtender client routes are used to allow and deny access for SSL VPN users to various network resources. Address objects are used to easily and dynamically configure access to network resources.
Tunnel All mode routes all traffic to and from the remote user over the SSL VPN NetExtender tunnel—including traffic destined for the remote user’s local network. This is accomplished by adding the following routes to the remote client’s route table:
NetExtender also adds routes for the local networks of all connected Network Connections. These routes are configured with higher metrics than any existing routes to force traffic destined for the local network over the SSL VPN tunnel instead. For example, if a remote user is has the IP address 10.0.67.64 on the 10.0.*.* network, the route 10.0.0.0/255.255.0.0 is added to route traffic through the SSL VPN tunnel.
Tunnel All mode is configured on the SSL VPN > Client Routes page.
SonicWALL SSL VPN supports NetExtender sessions using proxy configurations. Currently, only HTTPS proxy is supported. When launching NetExtender from the Web portal, if your browser is already configured for proxy access, NetExtender automatically inherits the proxy settings. The proxy settings can also be manually configured in the NetExtender client preferences. NetExtender can automatically detect proxy settings for proxy servers that support the Web Proxy Auto Discovery (WPAD) Protocol.
NetExtender provides three options for configuring proxy settings:
|
|
•
|
Automatically detect settings - To use this setting, the proxy server must support Web Proxy Auto Discovery Protocol (WPAD)), which can push the proxy settings script to the client automatically.
|
|
|
•
|
Use proxy server - You can use this option to specify the IP address and port of the proxy server. Optionally, you can enter an IP address or domain in the BypassProxy field to allow direct connections to those addresses and bypass the proxy server. If required, you can enter a user name and password for the proxy server. If the proxy server requires a username and password, but you do not specify them, a NetExtender pop-up window will prompt you to enter them when you first connect.
|
When NetExtender connects using proxy settings, it establishes an HTTPS connection to the proxy server instead of connecting to the SonicWALL security appliance. server directly. The proxy server then forwards traffic to the SSL VPN server. All traffic is encrypted by SSL with the certificate negotiated by NetExtender, of which the proxy server has no knowledge. The connecting process is identical for proxy and non-proxy users.
In order for users to be able to access SSL VPN services, they must be assigned to the SSLVPN Services group. Users who attempt to login through the Virtual Office who do not belong to the SSLVPN Services group will be denied access. The following sections describe how to configure user accounts for SSL VPN access:
To configure users in the local user database for SSL VPN access, you must add the users to the SSLVPN Services user group. To do so, perform the following steps:
|
Step 4
|
In the User Groups column, click on SSLVPN Services and click the right arrow to move it to the Member Of column.
|
To configure RADIUS users for SSL VPN access, you must add the users to the SSLVPN Services user group. To do so, perform the following steps:
|
Step 2
|
Click the Configure button for Authentication Method for login. The RADIUS Configuration window displays.
|
|
Step 4
|
In the Default user group to which all RADIUS users belong pulldown menu, select SSLVPN Services.
|
To configure LDAP users for SSL VPN access, you must add the LDAP user groups to the SSLVPN Services user group. To do so, perform the following steps:
|
Step 2
|
Navigate to the Users > Local Groups page and click the Import from LDAP button to import the LDAP user groups. The LDAP Import User Groups window displays.
|
|
Step 4
|
Click the Configure button for the SSLVPN Services group. The Edit Group window displays.
|
|
Step 6
|
In the User Groups column, click on the LDAP groups and click the right arrow to move them to the Member Of column.
|
Another option for configure LDAP users for SSL VPN access is to set the SSLVPN Services user group as the default LDAP User Group. To do so, perform the following steps:
|
Step 2
|
Set the Authentication method for login to either LDAP or LDAP + Local Users.
|
|
Step 3
|
Click the Configure button to launch the LDAP Configuration window.
|
|
Step 5
|
In the Default LDAP User Group pulldown menu, select SSLVPN Services.
|
The SSL VPN > Status page displays a summary of active NetExtender sessions, including the name, the PPP IP address, the physical IP address, login time, length of time logged in and logout time.
The following table provides a description of the status items.
The SSL VPN > Portal Settings page is used to configure the appearance and functionality of the SSL VPN Virtual Office web portal. The Virtual Office portal is the website that uses log in to launch NetExtender. It can be customized to match any existing company website or design style.
The following settings configure the appearance of the Virtual Office portal:
|
|
•
|
Login Message - The HTML code that is displayed when users are prompted to log in to the Virtual Office.
|
|
|
•
|
Example Template - Resets the Home Page Message and Login Message fields to the default example template.
|
|
|
•
|
Preview - Launch a pop-up window that displays the HTML code.
|
The following options customize the functionality of the Virtual Office portal:
|
|
•
|
Display Import Certificate Button - Displays an Import Certificate button on the Virtual Office page. This initiates the process of importing the SonicWALL security appliance’s self-signed certificate onto the web browser. This option only applies to the Internet Explorer browser on PCs running Windows 2000 or Windows XP.
|
The Customized Logo field is used to display a logo other than the SonicWALL logo at the top of the Virtual Office portal. Enter the URL of the logo in the Customized Logo field. The logo must be in GIF format of size 155 x 36, and a transparent or light background is recommended.
The SSL VPN > Client Settings page allows the administrator to enable SSL VPN access on zones and configure the client address range information and NetExtender client settings. It also displays which zones have SSL VPN access enabled.
The following tasks are configured on the SSL VPN > Client Settings page:
All of the zones on the SonicWALL security appliance are displayed in the SSL VPN Status on Zones section of the SSL VPN > Client Settings page. SSL VPN access must be enabled on a zone before users can access the Virtual Office web portal. A green button to the left of the name of the zone indicates that SSL VPN access is enabled. A red button indicates that SSL VPN access is disabled. To change the SSL VPN access for a zone, simply click the name of the zone on the SSL VPN > Client Settings page.
SSL VPN Access can also be configured on the Network > Zones page by clicking the configure icon for the zone.
The SSL VPN Client Address Range defines the IP address pool from which addresses will be assigned to remote users during NetExtender sessions. The range needs to be large enough to accommodate the maximum number of concurrent NetExtender users you wish to support plus one (for example, the range for 15 users requires 16 addresses, such as 192.168.200.100 to 192.168.200.115).
To configure the SSL VPN Client Address Range, perform the following steps:
|
Step 7
|
Navigate to the SSL VPN > Client Settings page.In the Start IP field, enter the first IP address in the client address range.
|
|
Step 8
|
In the End IP field, enter the last IP address in the client address range.
|
|
Step 9
|
In the DNS Server 1 filed, enter the IP address of the primary DNS server, or click the Default DNS Settings to use the default settings.
|
|
Step 10
|
(Optional) In the DNS Server 2 filed, enter the IP address of the backup DNS server.
|
|
Step 11
|
(Optional) In the DNS Domain field, enter the domain name for the DNS servers.
|
|
Step 12
|
In the User Domain field, enter the domain name for the users.
|
|
Step 13
|
(Optional) In the WINS Server 1 filed, enter the IP address of the primary WINS server.
|
|
Step 14
|
(Optional) In the WINS Server 2 filed, enter the IP address of the backup WINS server.
|
|
Step 15
|
In the Interface pulldown menu, select the interface to be used for SSL VPN services.
|
NetExtender client settings are configured on the bottom of the SSL VPN > Client Settings page. The following settings to customize the behavior of NetExtender when users connect and disconnect.
|
|
•
|
Exit Client After Disconnect - The NetExtender client exits when it becomes disconnected from the SSL VPN server. To reconnect, users will have to either return to the SSL VPN portal or launch NetExtender from their Programs menu.
|
|
|
•
|
Uninstall Client After Disconnect - The NetExtender client automatically uninstalls when it becomes disconnected from the SSL VPN server. To reconnect, users will have to return to the SSL VPN portal.
|
|
|
•
|
Create Client Connection Profile - The NetExtender client will create a connection profile recording the SSL VPN Server name, the Domain name and optionally the username and password.
|
|
|
•
|
User Name & Password Caching - Provide flexibility in allowing users to cache their usernames and passwords in the NetExtender client. The three options are Allow saving of user name only, Allow saving of user name & password, and Prohibit saving of user name & password. These options enable administrators to balance security needs against ease of use for users.
|
The SSL VPN > Client Routes page allows the administrator to control the network access allowed for SSL VPN users. The NetExtender client routes are passed to all NetExtender clients and are used to govern which private networks and resources remote user can access via the SSL VPN connection.
The following tasks are configured on the SSL VPN > Client Routes page:
Select Enabled from the Tunnel All Mode drop-down list to force all traffic for NetExtender users over the SSL VPN NetExtender tunnel—including traffic destined for the remote user’s local network. This is accomplished by adding the following routes to the remote client’s route table:
NetExtender also adds routes for the local networks of all connected Network Connections. These routes are configured with higher metrics than any existing routes to force traffic destined for the local network over the SSL VPN tunnel instead. For example, if a remote user is has the IP address 10.0.67.64 on the 10.0.*.* network, the route 10.0.0.0/255.255.0.0 is added to route traffic through the SSL VPN tunnel.
The Add Client Routes pulldown menu is used to configure access to network resources for SSL VPN users. Select the address object to which you want to allow SSL VPN access. Select Create new address object to create a new address object. Creating client routes causes access rules to automatically be created to allow this access. Alternatively, you can manually configure access rules for the SSL VPN zone on the Firewall > Access Rules page. For more information, see “Firewall > Access Rules” on page 327.
The SSL VPN > Virtual Office page displays the Virtual Office web portal inside of the SonicOS UI.
To view the SonicWALL SSL VPN Virtual Office web portal, navigate to the IP address of the SonicWALL security appliance. Click the link at the bottom of the Login page that says “Click here for sslvpn login.”
The following sections describe how to use NetExtender:
Windows clients must meet the following prerequisites in order to use NetExtender:
|
|
•
|
If the SonicWALL security appliance uses a self-signed SSL certificate for HTTPS authentication, then it is necessary to install the certificate before establishing a NetExtender connection. If you are unsure whether the certificate is self-signed or generated by a trusted root Certificate Authority, SonicWALL recommends that you import the certificate. The easiest way to import the certificate is to click the Import Certificate button at the bottom of the Virtual Office home page.
|
MacOS clients meet the following prerequisites in order to use NetExtender:
Linux clients must meet the following prerequisites in order to use NetExtender:
SonicWALL NetExtender is a software application that enables remote users to securely connect to the remote network. With NetExtender, remote users can virtually join the remote network. Users can mount network drives, upload and download files, and access resources in the same way as if they were on the local network.
The following sections describe how to install NetExtender on a Windows platform:
The following sections describe how to use NetExtender on a Windows platform:
The following section describe how to install and use NetExtender on a MacOS platform:
The following section describe how to install and use NetExtender on a Linux platform:
To use NetExtender for the first time using the Mozilla Firefox browser, perform the following:
|
Step 4
|
The Allowed Sites - Software Installation window is displayed, with the address of the Virtual Office server in the address window. Click Allow to allow Virtual Office to install NetExtender, and click Close.
|
|
Step 5
|
Return to the Virtual Office window and click NetExtender again.
|
|
Step 6
|
The Software Installation window is displayed. After a five second countdown, the Install Now button will become active. Click it.
|
Closing the windows (clicking on the x icon in the upper right corner of the window) will not close the NetExtender session, but will minimize it to the system tray for continued operation.
SonicWALL SSL VPN NetExtender is fully compatible with Microsoft Windows Vista 32-bit and 64-bit, and supports the same functionality as with other Windows operating systems.
It is recommended that you add the URL or domain name of your SonicWALL security appliance to Internet Explorer’s trusted sites list. This will simplify the process of installing NetExtender and logging in, by reducing the number of security warnings you will receive. To add a site to Internet Explorer’s trusted sites list, complete the following procedure:
|
Step 3
|
Click on the Trusted Sites icon and click on the Sites... button to open the Trusted sites window.
|
|
Step 5
|
Click Ok in the Trusted Sites and Internet Options windows.
|
To install and launch NetExtender for the first time using the Internet Explorer browser, perform the following:
|
Step 4
|
Click Instructions to add SSL VPN server address into trusted sites for help.
|
|
Step 7
|
Click on the Trusted Sites icon and click on the Sites... button to open the Trusted sites window.
|
|
Step 9
|
Click OK in the Trusted Sites and Internet Options windows.
|
After the first access and installation of NetExtender, you can launch NetExtender directly from your computer without first navigating to the SSL VPN portal. To launch NetExtender, complete the following procedure:
|
Step 2
|
Select the SonicWALL SSL VPN NetExtender folder, and then click on SonicWALL SSL VPN NetExtender. The NetExtender login window is displayed.
|
Complete the following procedure to configure NetExtender preferences:
|
Step 2
|
The Connection Profiles tab displays the SSL VPN connection profiles you have used, including the IP address of the server, the domain, and the username.
|
|
Step 4
|
The Settings tab allows you to customize the behavior of NetExtender.
|
|
Step 7
|
Select Minimize to the tray icon when NetExtender window is closed to have the NetExtender icon display in the system tray. If this option is not checked, you will only be able to access the NetExtender UI through Window’s program menu.
|
|
Step 9
|
Select Automatically reconnect when the connection is terminated to have NetExtender attempt to reconnect when it loses connection.
|
|
Step 10
|
Select Uninstall NetExtender automatically to have NetExtender uninstall every time you end a session.
|
|
Step 11
|
Select Disconnect an active connection to have NetExtender log out of all of your SSL VPN sessions when you exit a NetExtender session
|
SonicWALL SSL VPN provides users with the ability to run batch file scripts when NetExtender connects and disconnects. The scripts can be used to map or disconnect network drives and printers, launch applications, or open files or websites. To configure NetExtender Connection Scripts, perform the following tasks.
NetExtender Connection Scripts can support any valid batch file commands. For more information on batch files, see the following Wikipedia entry: http://en.wikipedia.org/wiki/.bat. The following tasks provide an introduction to some commonly used batch file commands.
|
Step 3
|
By default, the NxConnect.bat file contains examples of commands that can be configured, but no actual commands. Too add commands, scroll to the bottom of the file.
|
net use drive-letter\\server\share password /user:Domain\name
For example to if the drive letter is z, the server name is engineering, the share is docs, the password is 1234, the user’s domain is eng and the username is admin, the command would be the following:
For example, to disconnect network drive z, enter the following command:
For example, if the server name is engineering, the printer name is color-print1, the domain name is eng, and the username is admin, the command would be the following:
C:\Path-to-Application\Application.exe
start http://www.website.com
C:\Path-to-file\myFile.doc
SonicWALL SSL VPN supports NetExtender sessions using proxy configurations. Currently, only HTTPS proxy is supported. When launching NetExtender from the web portal, if your browser is already configured for proxy access, NetExtender automatically inherits the proxy settings.
To manually configure NetExtender proxy settings, perform the following tasks.
|
|
–
|
Automatically detect settings - To use this setting, the proxy server must support Web Proxy Auto Discovery Protocol (WPAD)), which can push the proxy settings script to the client automatically.
|
|
|
–
|
Use proxy server - Select this option to enter the Address and Port of the proxy server. Optionally, you can enter an IP address or domain in the BypassProxy field to allow direct connections to those addresses that bypass the proxy server. If required, enter a User name and Password for the proxy server. If the proxy server requires a username and password, but you do not specify them in the Preferences window, a NetExtender pop-up window will prompt you to enter them when you first connect.
|
|
Step 5
|
Click the Internet Explorer proxy settings button to open Internet Explorer’s proxy settings.
|
The NetExtender log displays information on NetExtender session events. The log is a file named NetExtender.dbg. It is stored in the directory: C:\Program Files\SonicWALL\SSL VPN\NetExtender. To view the NetExtender log, right click on the NetExtender icon in the system tray, and click View Log.
To view details of a log message, double-click on a log entry, or go to View > Log Detail to open the Log Detail pane.
To save the log, either click the Export icon or go to Log > Export.
To filter the log to display entries from a specific duration of time, go to the Filter menu and select the cutoff threshold.
To filter the log by type of entry, go to Filter > Level and select one of the level categories. The available options are Fatal, Error, Warning, and Info, in descending order of severity. The log displays all entries that match or exceed the severity level. For example, when selecting the Error level, the log displays all Error and Fatal entries, but not Warning or Info entries.
To view the Debug Log, either click the Debug Log icon or go to Log > Debug Log.
To clear the log, click on Log > Clear Log.
To disconnect NetExtender, perform the following steps:
You can also disconnect by double clicking on the NetExtender icon to open the NetExtender window and then clicking the Disconnect button.
When NetExtender becomes disconnected, the NetExtender window displays and gives you the option to either Reconnect or Close NetExtender.
NetExtender can be configured by the administrator to automatically notify users when an updated version of NetExtender is available. Users are prompted to click OK and NetExtender downloads and installs the update from the SonicWALL security appliance.
If auto-update notification is not configured, users should periodically launch NetExtender from the Virtual Office to ensure they have the latest version. Check with your administrator to determine if you need to manually check for updates.
The NetExtender utility is automatically installed on your computer. To remove NetExtender, click on Start > All Programs, click on SonicWALL SSL VPN NetExtender, and then click on Uninstall.
You can also configure NetExtender to automatically uninstall when your session is disconnected. To do so, perform the following steps:
|
Step 3
|
Select Uninstall NetExtender automatically to have NetExtender uninstall every time you end a session.
|
To view options in the NetExtender system tray, right click on the NetExtender icon in the system tray. The following are some tasks you can perform with the system tray.
To display the routes that NetExtender has installed on your system, click the Route Information option in the system tray menu. The system tray menu displays the default route and the associated subnet mask.
You can display connection information by mousing over the NetExtender icon in the system tray.
SonicWALL SSL VPN supports NetExtender on MacOS. To use NetExtender on your MacOS system, your system must meet the following prerequisites:
To install NetExtender on your MacOS system, perform the following tasks:
|
Step 12
|
Click Save to save the diagnostic report using the default nxdiag.txt file name in your NetExtender directory.
|
SonicWALL SSL VPN supports NetExtender on Linux. To use NetExtender on your Linux system, your system must meet the following prerequisites:
To install NetExtender on your Linux system, perform the following tasks:
|
Step 2
|
Click the NetExtender button. A pop-up window indicates that you have chosen to open the NetExtender.tgz file. Click OK to save it to your default download directory.
|
|
Step 4
|
Type the cd netExtenderClient command.
|
|
Step 5
|
Type ./install to install NetExtender.
|
|
Step 6
|
Launch the NetExtender.tgz file and follow the instructions in the NetExtender installer. The new netExtender directory contains a NetExtender shortcut that can be dragged to your desktop or toolbar.
|
|
Step 13
|
Click Save to save the diagnostic report using the default nxdiag.txt file name in your NetExtender directory.
|
for the user you want to edit, or click the Add User button to create a new user. The Edit User window is launched.
in the system tray and click on Preferences... The NetExtender Preferences window is displayed.