This tutorial describes how to increase the PHP post_max_size variable in cPanel with CloudLinux.
Step 1: Log into your cPanel account
Step 2: Under the Software section, click Select PHP Version:
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Step 3: Click on the Options menu
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Step 4: Change the post_max_size by clicking the drop-down option displayed in front of it. Then choose the appropriate limit as per your requirements.
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Congratulations, you have successfully increased the post_max_size PHP value.