Plesk inaccessible after enabling HTTP3 or Plesk Premium Antivirus cannot be enabled in Mail Server Settings

Symptoms

• Premium Antivirus for Servers extension is installed

• Plesk Premium Antivirus is selected in Tools & Settings > Mail Server Settings > Antivirus

• Enabling HTTP3 returns the following error:

  # plesk bin http3_pref --enable -panel -nginx
  Execution failed.
  Command: pleskrc
  Arguments: Array
  (
  [0] => sw-cp-server
  [1] => try-reload
  )
  
  Details: Job for sw-cp-server.service failed.
  See "systemctl status sw-cp-server.service" and "journalctl -xe" for details.
  
  
  exit status 1

• Accessing Plesk returns a 502 Bad Gateway error

• The sw-cp-server service fails to start:

  # systemctl status sw-cp-server
  ● sw-cp-server.service - Startup script for Plesk control panel server
  Loaded: loaded (/usr/lib/systemd/system/sw-cp-server.service; enabled; vendor preset: disabled)
  Drop-In: /usr/lib/systemd/system/sw-cp-server.service.d
  └─respawn.conf
  Active: activating (auto-restart) (Result: exit-code) since Wed 2024-05-15 17:03:08 UTC; 1s ago
  Process: 2824712 ExecReload=/usr/sbin/sw-cp-serverd -q -t (code=exited, status=1/FAILURE)
  Process: 2825442 ExecStartPre=/usr/sbin/sw-cp-serverd -q -t (code=exited, status=1/FAILURE)
  Main PID: 2705176 (code=exited, status=0/SUCCESS)

• The following error can be found when running journalctl -xeu sw-cp-server:

  sw-cp-serverd[106784]: nginx: [emerg] duplicate listen options for 0.0.0.0:8443 in /etc/sw-cp-server/conf.d/http3_plesk.inc:1

• Selecting Premium Antivirus for Servers in Tools & Settings > Mail Server Settings > Antivirus fails if HTTP3 is already enabled:

  Execution drwebmng has failed with exit code 1, stdout: , stderr: nginx: [emerg] duplicate listen options for 0.0.0.0:8443 in /etc/sw-cp-server/conf.d/http3_plesk.inc:1 nginx: configuration file /etc/sw-cp-server/config test failed Unable to setup sw-cp-server to receive connections from drweb.

Cause

Resolution

Workaround

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