How to Generate a HAR File

Occasionally, you might encounter a site that doesn't load the waterfall view in page load very nicely. This won't happen often, but when it does, it's important that we obtain diagnostic information so that we can resolve the issue, and make your interaction with the ThousandEyes platform as enjoyable and seamless as possible.

When this happens, and the interaction is with a site behind your own firewall, ThousandEyes might request that you generate a HAR file of your interaction with the site. This is most easily done in the built-in developer tools in either Firefox or Chrome. Instructions are below for each browser.

Using Firefox

  1. Open the site you want to profile. If you need to enter any authentication information, do so in order to open the site.

  2. Go to Tools > Web Developer > Network.

  3. In the developer tools panel now docked at the bottom of your Firefox window, make sure the Network tab is selected.

  4. In the site you are profiling, do the action you want to record. Firefox's developer tools automatically record your actions.

  5. In the developer tools panel, right-click in the columns of the table, and select Save All As HAR.

  6. Name the file and save it, and email it to for analysis.

Using Chrome

  1. From the View menu, click Developer > Developer Tools. The developer tools will either launch in a separate window, or will be docked at the bottom of your browser page.

  2. Click the Network tab, then click the black circle in the toolbar at the bottom of the window.

    This will start recording a page load, and will change the black circle into a red circle.

  3. Open the website you wish to record, and enter any authentication information that is required.

  4. Once complete, click the record button again, and the recording will stop.

  5. Once the recording is complete, right-click anywhere in the developer console and select Save as HAR with Content. This will create a HAR file in the location you specify.

    An example of is shown below.

If you have questions about how to generate the file, or how this information is used, contact

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