Frequently Asked Questions

General

• What are the supported Hypervisor Platforms for a Kemp Virtual LoadMaster?

  The latest list of supported hypervisors for Virtual LoadMaster is available on our support site. Virtual LoadMaster is also available in the Marketplace on the Azure and AWS clouds.

• Templates for the LoadMaster

  Templates are available to add services to the Loadmaster for example services like MAPI, SMTP, and HTTP/HTTPS. To add templates first go to the Kemp documentation site at the following link https://www.kemptechnologies.com/documentation under templates download the templates that you require. The templates will have a .tmpl extension when downloaded. To add the templates to the Loadmaster.

• Does the Kemp LoadMaster come with support?

  Every new Kemp LoadMaster purchase requires the additional minimum purchase of 1 Year Standard Support Subscription. This Subscription level includes 5x10 support, software updates as well as security notifications and patches. Enterprise and Enterprise Plus Subscription options are also available which provide additional functionality, services and 24x7 Support.

• What are the Advantages and disadvantages of Direct Server Return (DSR)?

  Advantages: Direct Server Return is ideal for high-bandwidth requirements such as content delivery networks, video games and multimedia. DSR keeps existing IP addresses of the Real Servers Disadvantages:

• What is the HyperText Transfer Protocol (HTTP)

  The Hypertext Transfer Protocol, or HTTP, is the most widely used Application layer protocol in the world today. It forms the basis of the World Wide Web. Its main objective is to provide a method for the retrieval of Hypertext Markup Language (HTML) and other application from any Web sites. HTTP was first developed in the early 1990s and has been through three main versions:

• How does healthchecking work?

  Essentially healthchecking works by requesting something and examining the response. Healthchecking can be done at different layers of the TCP/IP stack. The higher in the stack, the better the quality of the healthcheck at determining overall application health.

• What is Drain Stop and when does it affect traffic?

  Drain stopping allows user sessions to be gracefully removed from disabled servers. This allows users to finish their session before removing servers for maintenance.

• Why do my real servers come in and out of service frequently?

  This is what's known as 'server flapping.' This occurs when healthcheck settings are too aggressive and incorrectly marks real servers as down when they are not failing. This can be eliminated by changing the healthcheck settings in Rules and Checking > Check Parameters > Service Check Parameters. Check Interval (sec) The time in seconds between healthchecks. Connect (sec) The time in seconds before LoadMaster abandons a healthcheck.

• How can I redirect the root of the webserver to a specific directory

  Typically, this is better to configure this sort of redirect on your real servers, however you can utilize Header Modification to achieve the same result.

• How can I redirect traffic from HTTP to HTTPS?

  To redirect from HTTP to HTTPS, create a virtual service on the IP you use for HTTPS on port 80. This service will act as a redirector and does not need real servers. Once created, scroll down to Advanced Properties. Under Not Available Redirection Handling, select '302 Found' as the Error Code and specify the URL you wish to redirect to as the Redirect URL. You may use the wildcards %h and %s to represent the requested hostname and URI respectively.

• Where can I specify real server check parameters for my virtual services?

  In addition to setting the type of healthcheck to perform on a per virtual service basis, administrators have the ability to specify health check parameters from be selecting the Rules & Checking > Check Parameters option.

• What is a simple way to redirect my http traffic to https?

  Create a 443 VS and add your Real Servers In the 'Advanced Properties' of your '443 VS' in the 'Not Available Redirection Handling' section, select the 'Select 302 Found' option in the 'Error Code' drop-down list. Specify the URL you want to redirect to and select 'Set Redirect URL'. This will create automatic port 80 Redirect VS. Here is some example URLs, for the URL %h defines host name and %s defines the URI

• How do I know the current status of my LoadMaster’s support contract?

  The best method to determine when the support contract ends on a specific LoadMaster unit is to e-mail our Sales Department at sales@kemptechnologies.com using the format listed below. Subject: Support Contract Query Body: Contact Name: Company Name: Serial Number of LoadMaster(s):