gzip compression is not enabled for a domain in Plesk, when nginx is enabled

Symptoms

• gzip compression has been enabled for a domain according to this KB article.

• Online optimization test tools like Google PageSpeed Insights show that gzip compression is not enabled for a this domain.

Cause

Responses are compressed by Apache and then decompressed by nginx when the options Smart static files processing and Serve static files directly by nginx are enabled for a domain in Plesk at Domains > example.com > Apache & nginx Settings.

Resolution

Apply one of the following solutions:

• Enable gzip compression directly in nginx (Recommended).

• Configure nginx to keep responses as is:

  1. Log in to Plesk.

  2. Go to Domains > example.com > Apache & nginx Settings.

  3. Disable the options Smart static files processing and Serve static files directly by nginx

  4. Apply the changes.