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How-to Flush DNS

Please follow the below instructions for workstations. Read further for specific details for network hardware.

The DNS cache temporarily stores the names of Web sites you have visited recently and the network addresses associated with them. Sometimes incorrect DNS entries appear and keep you from getting to the correct Web site.

Flush the DNS Cache on your Windows workstation:

  1. Click the Start button and select Run. Enter cmd in the box that appears, then click OK or press Enter.
  2. At the command prompt that appears with the black background, type ipconfig /flushdns, then press Enter.
  3. You should see a message that says "Successfully flushed the DNS Resolver Cache.”
  4. Type EXIT and press Enter to close the command window.

Note: After performing the flush, we recommend that each machine have the temporary internet files cleared. See the links at the bottom of these instructions for details.

Flush the DNS Cache on your Mac workstation (Mac OSX 10.5 & 10.6):

  1. Navigate to your Applications folder, open Utilities, and double click on Terminal.
  2. At the Terminal screen, type dscacheutil -flushcache, then press Enter. There should be no confirmation this was completed.
  3. Click on Terminal then Quit to close the Terminal window
  4. Flush the DNS Cache on your Mac workstation (Mac OSX 10.7 & 10.8):
  5. Navigate to your Applications folder, open Utilities, and double click on Terminal.
  6. At the Terminal screen, type sudo killall -HUP mDNSResponder, then press Enter. There should be no confirmation this was completed.
  7. Click on Terminal then Quit to close the Terminal window

Note: After performing the flush, we recommend that each machine have the temporary internet files cleared. See the links at the bottom of these instructions for details.

What's Next:

Try to login again or start the activity again and verify that it loads properly. If an activity is not loading and/or images not appearing on test, try flushing the DNS using the steps above. If the computer is in a customized network configuration, such as at a school or connected to a virtual network via VPN, the network’s DNS tables may need flushed or updated. Please contact your network support for assistance in this process.

Note: You may also need to clear your browser cache after flushing your DNS. Please follow the links below for instructions on clearing cache in Firefox, IE and Safari.

For network devices and network administrators:

The DNS cache for network devices can also store outdated information and needs to be cleared. Please follow your vendor’s instructions for clearing the DNS cache for all content filters, firewalls, proxy servers, and packet shapers. This will cause the cache to refresh all records for Study Island.

IP Addresses vs. URLs

Some customers may use devices to filter traffic specific to Study Island. Many devices allow administrators to configure the filter by URL or IP address or range. Due to the dynamic hosting of Study Island, IP ranges and addresses can change unexpectedly. If you configure your networks using IP as opposed to URLs, we recommend using the *.studyisland.com wildcard to allow all traffic to pass regardless of IP address. If you must configure your network with IP addresses or ranges, please contact Edmentum for more information. 

If you any questions or concerns about these recommendations, please contact us by calling 800.419.3191 or emailing support@studyisland.com.