Plesk backups to cloud storage fails: Unable to create the remote backup: assign: Bad file descriptor

Symptoms

• Backups to cloud storage, such as  Microsoft OneDrive, AWS S3, and Dropbox, fail with the error:

  PLESK_ERROR: Unable to create the remote backup: assign: Bad file descriptor [system:9 at unix/plesk/packages/thirdparty/buck-out/gen/libs/boost/1.88.0/headers.header_dirs_0/boost/asio/detail/impl/reactive_descriptor_service.ipp:120:5 in function 'boost::system::error_code boost::asio::detail::reactive_descriptor_service::assign(implementation_type&, const native_handle_type&, boost::system::error_code&)']

• Error in Plesk backup logs:

  CONFIG_TEXT: [2025-11-24 12:51:12.469|185294] INFO: The return code was 0
  The output on STDOUT was:
  {"type":"quickXor","blockSize":104857600}
  No output on STDERR were performed by the utility
  The last error was:
  Resource temporarily unavailable
  [2025-11-24 12:51:12.469|185294] INFO: RepositoryTransportExternal::OpenFile: backup_2511241251.tar, wb, 0
  [2025-11-24 12:51:12.469|185294] INFO: Executing utility: /opt/psa/admin/bin/backup_restore_helper --extension-transport ext://one-drive-backup/server/ -operation open-write -path backup_2511241251.tar
  [2025-11-24 12:51:12.471|185294] INFO: Cancel export
  [2025-11-24 12:51:12.471|185294] INFO: RepositoryTransportExternal::OpenFile: backup_2511241251.tar, wb, 0
  [2025-11-24 12:51:12.471|185294] INFO: Executing utility: /opt/psa/admin/bin/backup_restore_helper --extension-transport ext://one-drive-backup/server/ -operation open-write -path backup_2511241251.tar
  [2025-11-24 12:51:12.488|185294] INFO: Failed to close an archiver: unix/plesk/packages/thirdparty/buck-out/gen/libs/boost/1.88.0/headers.header_dirs_0/boost/asio/posix/basic_descriptor.hpp(139): Throw in function boost::asio::posix::basic_descriptor<Executor>::basic_descriptor(const executor_type&, const native_handle_type&) [with Executor = boost::asio::any_io_executor; executor_type = boost::asio::any_io_executor; native_handle_type = int]
  Dynamic exception type: boost::wrapexcept<boost::system::system_error>
  std::exception::what: assign: Bad file descriptor [system:9 at unix/plesk/packages/thirdparty/buck-out/gen/libs/boost/1.88.0/headers.header_dirs_0/boost/asio/detail/impl/reactive_descriptor_service.ipp:120:5 in function 'boost::system::error_code boost::asio::detail::reactive_descriptor_service::assign(implementation_type&, const native_handle_type&, boost::system::error_code&)']

• Server is using openvz with older kernel:

  # uname -a
  Linux 4.19.0 #1 SMP Mon Mar 16 15:39:59 MSK 2020 x86_64 GNU/Linux
   

  # virt-what
  openvzCause

   

Cause

Product Bug #PPPM-15233 Backups creation to cloud storage fails on OpenVZ.

Resolution

Until the bug is fixed, replacing the pmm-ras from Plesk version 18.0.73 can be used as a workaround. Below is the example for Debian 11 OS:

1. Connect to the Plesk server via SSH.

2. Create a temporary directory and navigate to it:

   # mkdir /root/tmp && cd /root/tmp

3. Download the plesk-backup-utilities package for your OS:

   # wget https://autoinstall.plesk.com/pool/PSA_18.0.73_17971/dist-deb-Debian-11.0-x86_64/base/plesk-backup-utilities_18.0-v.debian.11+p18.0.73.5+t251124.2020_amd64.deb
    

   Note: Make sure that the downloaded .deb is based on the OS type

4. Extract the content of the package within the temporary directory (if you downloaded the package for AMD64, make sure to replace the package name with the actual one):

   # dpkg-deb -R /root/plesk-backup-utilities_18.0-v.debian.11+p18.0.73.5+t251124.2020_amd64.deb ./

5. Backup the current pmm-ras:

   # cp -a /opt/psa/admin/sbin/pmm-ras{,.back}

6. Replace it with the one downloaded in step 2:

   # cp ./opt/psa/admin/sbin/pmm-ras /opt/psa/admin/sbin/pmm-ras