While startup "ORA-00845: MEMORY_TARGET not supported on this system"

 While Startup got "While startup "ORA-00845: MEMORY_TARGET not supported on this system"

SQL> startup
ORA-00845: MEMORY_TARGET not supported on this system

Solution - on Linux not enough space allocated to /dev/shm during setup as below:

tmpfs                  1.4G   96K  1.4G   1% /dev/shm   >> Need to increase it

Solution:

[root@oranode1 ~]# mount -t tmpfs shmfs -o size=2048m /dev/shm

[oracle@oranode1 ~]$ df -h /dev/shm

Filesystem      Size  Used Avail Use% Mounted on

shmfs           2.0G  1.5G  576M  72% /dev/shm

After above DB came up fine:

[oracle@oranode1 ~]$ sqlplus / as sysdba

SQL*Plus: Release 12.2.0.1.0 Production on Wed Feb 13 07:55:47 2020

Copyright (c) 1982, 2016, Oracle.  All rights reserved.

Connected to an idle instance.

SQL> startup

ORACLE instance started.

Total System Global Area 1593835520 bytes

Fixed Size                  8621184 bytes

Variable Size            1459618688 bytes

Database Buffers          117440512 bytes

Redo Buffers                8155136 bytes

Database mounted.

Database opened.

SQL>

Thanks