Question
Why would a "Page Cannot Be Displayed" error (or a similar message) appear in the browser when trying to access intranet servers through a Finjan appliance?
Answer
When a Vital Security Web Appliance receives a request from a browser, the appliance attempts to resolve the IP address of the destination site. By default, the appliance first checks its internal hosts file for sites that were defined manually by the administrator. When the site is not listed in the hosts file, the appliance queries the DNS servers. If the appliance does not obtain the IP of the destination host, an error message will be displayed in the browser. The actual error message can vary in different environments.
When intranet traffic (transactions involving internal web hosts) is passed through the Vital Security Web Appliance, it is important that the appliance will be able to resolve the names of internal hosts. These hosts can be manually defined in the appliance's hosts file (go to Advanced Settings -> Network Settings -> Host Addresses in the appliance's Setup Console). However, this can be a time-consuming task that will require regular maintenance as more intranet hosts are added.
It is usually preferable to configure the Vital Security Web Appliance to communicate with DNS servers that can resolve both hostnames on the public Internet and internal hostnames. Additionally, since requests to intranet sites frequently just contain the host portion of the site's fully qualified domain name, the appliance should be aware of all relevant Search Domains. This is very important, even if users always access internal sites by their fully qualified domain names since internal links on the sites might only contain their hostname. If the Search Domains are not configured, transactions involving internal web sites might be unsuccessful.
Search Domains can be configured during the appliance's initial setup (using the Setup Wizard). To add Search Domains at a later point in time, please follow the steps below:
Software Version
8.4.X
8.5.0
- This article applies to:
- NG 1000
- NG 5000
- NG 6000
- NG 8000
- This article was previously published as:
- Finjan KB 1639