Unable to open Advanced Monitoring extension: Execution extension has failed with exit code 127

Symptoms

• Plesk is installed on Ubuntu server

• Advanced Monitoring extension displaying the following error:

  PLESK_ERROR: Could not check if Advanced Monitoring was installed correctly: Execution extension has failed with exit code 127, stdout: , stderr: /opt/psa/admin/sbin/modules//grafana/grafana-cli: line 2: /usr/sbin/grafana-cli: No such file or directory

• “Advanced Monitoring” extension and and Grafana are installed:

  # plesk bin extension –list | grep -E “grafana|monitoring”
  grafana – Grafana
  monitoring – Advanced Monitoring

• The file /usr/sbin/grafana-cli is missing:

  # ls -lha /usr/sbin/grafana-cli
  ls: cannot access ‘/usr/sbin/grafana-cli’: No such file or directory

• Grafana package is not installed:

  # dpkg –list | grep grafana
  (Empty Output)

• The following error can be found:

  # python2 -c 'import urllib2 ; print urllib2.urlopen("https://packages.grafana.com/gpg.key").read()'
   . . . 
   urllib2.URLError: <urlopen error [SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed (_ssl.c:590)>

Cause

Broken CA certificates configuration on OS level caused by Ubuntu bug with ID 396818

Resolution

1. Connect to the server via SSH

2. Move /usr/lib/ssl directory:

   # mv /usr/lib/ssl /usr/lib/ssl_old

3. Reinstall CA certificates:

   # apt-get install --reinstall openssl ca-certificates

4. Ensure that the certificate can be obtained without any errors:

   # python2 -c 'import urllib2 ; print urllib2.urlopen("https://packages.grafana.com/gpg.key").read()'
    -----BEGIN PGP PUBLIC KEY BLOCK----- 
    Version: GnuPG v1 
    mQENBFiHXVIBCADr3VDEAGpq9Sg/xrPVu1GGqWGXdbnTbbNKeveCtFHZz7/GSATW
    ...

5. Reinstall Grafana extension:

   # plesk bin extension –uninstall grafana
   # plesk bin extension –install grafana

6. Verify Grafana package was installed successfully:

   # dpkg –list | grep grafana
   ii grafana 6.3.6 amd64 Grafana

7. Log in to Plesk GUI

8. Go to Advanced Monitoring

   In case the following error message is shown, click on Fix installation:

   PLESK_ERROR: The grafana-simple-json-datasource plugin is not installed.