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Mitratech Success Center

How to gather the HAR file from Chrome, Firefox, Safari and IE

HAR files are used to gather performance data from the end-users' web browser. It will capture objects, and response calls that a webpage generates.

Additional metrics that can be gathered by HAR are:

  • Length of time that it takes to connect to the server
  • Length of time to gather DNS information
  • Length of time that it takes to transfer assets from the server to the browser
  • Length of time that an object takes to be requested

 

How to generate a HAR and log file in Chrome

  1. Open up chrome browser and/ or install Chrome
  2. Click F12 and you will see the developer console on the right hand side appears
  3. Select Network tab, check Preserve log checkbox
  4. Click second button from left to clear history (highlighted)Browser F12 01.png
  5. Put the URL we have requested into the browser and wait until the final page loads. 
  6. In the results grid right click 'Save all as HAR with content'

Browser F12 02.png

7. Send Mitratech the exported HAR File(s) so our Teams can see all the network communications. 

 

How to generate a HAR and log file in Firefox

  1. Open Firefox.
  2. In Firefox, go to the webpage in question.
  3. Select the Firefox menu > Web Developer > Network.
  4. Within the Networks tab, select Preserve log option.
  5. In the center of the Networks tab select refresh.
  6. Refresh the page and allow Firefox to record the browser-website interaction. 
  7. Once the page is loaded, right click and "Save All As HAR".
  8. Select the Console tab and right-click on in the console box. Select all and Copy Message 
  9. Copy log messages to the preferred text editor.
  10. Upload the HAR and log files to the support ticket.

 

How to generate a HAR and log file in Safari

  1. Open Safari.
  2. In Safari, go to the webpage in question.
  3. Enable Developers Tool: Safari > Preferences > Advance > Click Show Develop menu in menu bar
  4. Select Develop in menu > Show Web Inspector > Select Network tab
  5. Within the Networks tab, select Preserve log option.
  6. Refresh the page and allow Safari to record the browser-website interaction. 
  7. Once the page is loaded, click on Export on the top right in the window of the Network tab.
  8. Select the Console tab and screen capture the errors.
  9. Upload the HAR and console screenshot files to the support ticket.

 

How to generate a HAR and log file in Internet Explorer (IE)

  1. Open IE.
  2. In IE, go to the webpage in question.
  3. To open Developers Tool, press the F12 key on your keyboard, or you may find the Developers Tool in the menu.
  4. In the Developers Tool menu > Network panel and then deselect the Clear entries on navigate option. (Default)
  5. Select Start Profiling Session/Start Capture.
  6. Refresh the page and allow IE to record the browser-website interaction. 
  7. Once the page is loaded, click on Export as HAR/Export capture traffic icon and save
  8. Click on the Console tab and look for any errors/warnings reported. If errors are shown, please right-click on the console errors and select Copy all. 
  9. Upload the HAR and log files to the support ticket.