ORA-00845: MEMORY_TARGET not supported on this system

srvctl start asm

fails with the following error.

[oracle@sbstandby ~]$ srvctl start asm
PRCR-1079 : Failed to start resource ora.asm
CRS-2674: Start of 'ora.LISTENER.lsnr' on 'sbstandby' failed
CRS-5017: The resource action "ora.asm start" encountered the following error: 
ORA-00845: MEMORY_TARGET not supported on this system
. For details refer to "(:CLSN00107:)" in "/u01/app/grid/diag/crs/sbstandby/crs/trace/ohasd_oraagent_oracle.trc".

CRS-2674: Start of 'ora.asm' on 'sbstandby' failed

ohasd_oraagent_oracle.trc shows this

2023-12-21 20:38:03.612 : USRTHRD:1902495488: [     INFO] {0:0:4436} InstConnection::disConnect 100 this:0x7fcc4002f220 get SessionLock 0x7fcc4002aa60 for OCISessionEnd
2023-12-21 20:38:03.613 : USRTHRD:1902495488: [     INFO] {0:0:4436} InstConnection::~InstConnection destructor 999 this pConnxn:0x7fcc4002f220 spid:
2023-12-21 20:38:03.613 :CLSDYNAM:1902495488: [ ora.asm]{0:0:4436} [start] InstAgent::startInstance 380 throw excp what:ORA-00845: MEMORY_TARGET not supported on this system

2023-12-21 20:38:03.613 :CLSDYNAM:1902495488: [ ora.asm]{0:0:4436} [start] InstAgent::start 500 exception OCIException
2023-12-21 20:38:03.613 :CLSDYNAM:1902495488: [ ora.asm]{0:0:4436} [start] ORA-00845: MEMORY_TARGET not supported on this system

2023-12-21 20:38:03.613 :CLSDYNAM:1902495488: [ ora.asm]{0:0:4436} [start] Agent::commonStart Exception OCIException
2023-12-21 20:38:03.613 :CLSDYNAM:1902495488: [ ora.asm]{0:0:4436} [start] clsnUtils::error Exception type=2 string=
CRS-5017: The resource action "ora.asm start" encountered the following error:
ORA-00845: MEMORY_TARGET not supported on this system
. For details refer to "(:CLSN00107:)" in "/u01/app/grid/diag/crs/sbstandby/crs/trace/ohasd_oraagent_oracle.trc".

2023-12-21 20:38:03.613 :    AGFW:1902495488: [     INFO] {0:0:4436} sending status msg [CRS-5017: The resource action "ora.asm start" encountered the following error:
ORA-00845: MEMORY_TARGET not supported on this system
. For details refer to "(:CLSN00107:)" in "/u01/app/grid/diag/crs/sbstandby/crs/trace/ohasd_oraagent_oracle.trc".
] for start for resource: ora.asm sbstandby 1
2023-12-21 20:38:03.615 :CLSDYNAM:1902495488: [ ora.asm]{0:0:4436} [start] (:CLSN00107:) clsn_agent::start }
2023-12-21 20:38:03.615 :    AGFW:1902495488: [     INFO] {0:0:4436} Command: start for resource: ora.asm sbstandby 1 completed with status: FAIL
2023-12-21 20:38:03.615 :    AGFW:1894090496: [     INFO] {0:0:4436} Agent sending reply for: RESOURCE_START[ora.asm sbstandby 1] ID 4098:219617
2023-12-21 20:38:03.615 :CLSDYNAM:1902495488: [ ora.asm]{0:0:4436} [check] InstAgent::checkState 030 new gimh oracleSid:+ASM
2023-12-21 20:38:03.616 :CLSDYNAM:1902495488: [ ora.asm]{0:0:4436} [check] Gimh::check condition changes to (GIMH_NEXT_NUM) 0(Abnormal Termination) exists

Resolution :

In the server, /dev/shm is 1.8G

[root@sbstandby ~]# df -h /dev/shm
Filesystem      Size  Used Avail Use% Mounted on
tmpfs           1.8G   16K  1.8G   1% /dev/shm

Unmounted and remounted tmpfs.

[root@sbstandby ~]# mount -t tmpfs shmfs -o size=8192m /dev/shm
[root@sbstandby ~]# 

[root@sbstandby ~]# df -h /dev/shm
Filesystem      Size  Used Avail Use% Mounted on
shmfs           8.0G     0  8.0G   0% /dev/shm

Let's restart ASM now.

[oracle@sbstandby ~]$ srvctl status asm
ASM is not running.
[oracle@sbstandby ~]$ srvctl start asm
[oracle@sbstandby ~]$ srvctl status asm
ASM is running on sbstandby

Issue fixed.

Cause :

The Automatic Memory Management functionality uses /dev/shm on Linux for SGA and PGA management. The errors occur if either MEMORY_TARGET or MEMORY_MAX_TARGET is configured larger than the configured /dev/shm size, or if /dev/shm is mounted incorrectly.