Unable to install system updates via Plesk: Update information is not available for package(s)

Issue Symptoms

• Unable to install system updates via Plesk:

  PLESK_ERROR: Update information is not available for package(s)

• Updating system packages via a command-line interface results in the following error messages:

  # yum update
  32:bind-utils-9.9.4-51.el7.x86_64: [Errno 5] [Errno 12] Cannot allocate memory
  jasper-devel-1.900.1-31.el7.x86_64: [Errno 5] [Errno 12] Cannot allocate memory
  libcurl-7.29.0-42.el7.x86_64: [Errno 5] [Errno 12] Cannot allocate memory
  freetype-devel-2.4.11-15.el7.x86_64: [Errno 5] [Errno 12] Cannot allocate memory
  psmisc-22.20-15.el7.x86_64: [Errno 5] [Errno 12] Cannot allocate memory
  samba-4.6.2-10.el7_4.x86_64: [Errno 5] [Errno 12] Cannot allocate memory
  libfontenc-1.1.3-3.el7.x86_64: [Errno 5] [Errno 12] Cannot allocate memory
  libselinux-devel-2.5-11.el7.x86_64: [Errno 5] [Errno 12] Cannot allocate memory
  binutils-2.25.1-32.base.el7_4.1.x86_64: [Errno 5] [Errno 12] Cannot allocate memory
  glibc-headers-2.17-196.el7.x86_64: [Errno 5] [Errno 12] Cannot allocate memory
  1:perl-IO-Zlib-1.10-292.el7.noarch: [Errno 5] [Errno 12] Cannot allocate memory
  gobject-introspection-1.50.0-1.el7.x86_64: [Errno 5] [Errno 12] Cannot allocate memory
  samba-libs-4.6.2-10.el7_4.x86_64: [Errno 5] [Errno 12] Cannot allocate memory

• There is less than 100MB free RAM on the server:

  # free -h
         total   used   free    shared   buff/cache   available
  Mem:    1.0G   499M    23M      263M         501M        378M
  Swap:   256M   170M    85M

Conditions

Insufficient RAM on the server.

Resolution

Allocate additional RAM to the server.

Additional Information

• Plesk Documentation: Hardware Requirements for Plesk Onyx