webpage has a redirect loop in magento 2

step: 1 Go to Phpmyadmin
          search core_config_data
step: 2 Edit the rows entitled web/unsecure/base_url and  web/secure/base_url
        http://127.0.0.1/magento_sample/  and
https://127.0.0.1/magento_sample/
step: 3 Edit the row web/url/redirect_to_base to 0 instead of 1
step: 4 Clear contents of both var/cache and var/sessions folders.

cheack your Admin url Work.....

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