ORA-27301 OS failure message: No buffer space available

If you get this error

ORA-27300: OS system dependent operation:sendmsg failed with status: 105
ORA-27301: OS failure message: No buffer space available
ORA-27302: failure occurred at: sskgxpsnd2

The solution is to:

  1. Lower MTU to 16436. To do this, add following to /etc/sysconfig/network-scripts/ifcfg-lo or replace the value if MTU is already set in this configuration file.
    MTU=16436
  2. Save the file, exit and restart the network service by running:
    systemctl restart network.service
  3. Calculate the value for vm.min_free_kbytes to be 0.4 % of the total physical memory and multiply by the number of NUMA nodes.
    total=$(awk ‘/MemTotal:(.)/{print $2 }’ /proc/meminfo) numa_count=$(lscpu | awk ‘/^NUMA node(s)(.)/{print $3 }’)
    min_free_kb=$(expr $total / 250 * 1) # this is the
  4. Increase the value of vm.min_free_kbytes accordingly. This can be done by adding following a new sysctl configuration.
    echo “vm.min_free_kbytes=$min_free_kb” > /etc/sysctl.d/99-vm_min_free_kbytes.conf

This will take the value of $min_free_kb from the previous step!

  1. load the new values

sysctl –system

  1. Verify the new value has been applied correctly.
    sysctl vm.min_free_kbytes