Shipper Pre Flight check stuck

Shippers Pre Flight check is stuck at 99%, debug log enabled isn’t giving any clue regarding the issue.

Please check chat notes for more info.

  • Nithin
    • Support Wizard

    Hi victor,

    On troubleshooting the issue further, it was more related to a rate-limiting added by your host your server side.

    For some odd reason, the SFTP login is no longer working in our side, so we have added the following code inside the Shipper Pro plugin via the Plugin Editor in WordPress dashboard.

    function my_shipper_delay() { sleep(2); }
    add_action( 'shipper_runner_pre_request_tick', 'my_shipper_delay' );

    The above function is added inside the shipper.php file in the shipper plugin folder. Once added, the Shipper Pre Flight check worked fine and completed the process.

    To avoid the code to get overwritten in the next plugin update, please make sure to add the code as a mu-plugins as menioned below:

    function my_shipper_delay() { sleep(2); }
    add_action( 'shipper_runner_pre_request_tick', 'my_shipper_delay' );

    You can check this article on how to make use of mu-plugins:

    Once the Pre Flight check is run, you should see a screen like this with few warnings:

    Which is due to Large files present in your system which the Shipper detects. Clicking the “Begin Migration” button should start the migration process.

    However, it would be better to exclude any big files from migration, such as zip files etc by clicking the “Files” tab as shown in the above screenshot.

    And by excluding the zip files, should help reduce the migration load. Once done, you can start the migration. Please do check, and let us know if you have any further query.



  • victor
    • Flash Drive

    No luck. I removed all large files and still getting nowhere with this SHIPPER plugin. Still giving me the LONG NAME FILE errors eventhough I dismissed those files. It seems that SHIPPER works ONLY in very ideal, not typical, conditions. I have adjusted my source site to all ideal condtitions (removed all large files and left only the wp files and theme, dismissed all long name files, etc..) but still getting the preflight warnings. I went ahead anyways to to the export and it never finished! Please help further.

  • Nithin
    • Support Wizard

    Hi victor,

    Sorry for the delay in getting back to you. I could also notice SSL certificate error in the source website which wasn't present initially in the website side before.

    Just bringing this into your attention in case it wasn't an issue before, and please do make sure to fix any such issues.

    I just checked the website, and I could notice the Migration has been started and is at 80%:

    As seen in the screenshot, it can take 18h – 28hours. If you think the Shipper has been working for too long, then the mentioned hours, then please stop the migration, and update the plugins to it's the latest version in both WordPress installs.

    Increase the memory limit to at least the following rules in both source, and destintion wesbite:

    upload_max_filesize = 128M
    post_max_size = 256M
    memory_limit = 512M
    file_uploads = On
    max_execution_time = 800

    Please check this link for more info:

    Once done, please check whether re-running a new migration makes an improvement or not. The above steps are meant only if the Shipper was taking longer time than expected as mentioned. The amount of time the plugin takes to perform entirely depends upon the server, and how the plugin could connect to the servers with the available resources.

    When an issue occurs, I'm afraid the only workaround would be to increase the resources, and re-run a new migration to see whether the migration works.

    Please do let us know that goes, and we'll make sure to troubleshoot further if needed. Have a good day ahead.

    Kind Regards,


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