Oracle 12C RAC安装grid时root.sh报错ORA-00845

Oracle 12C RAC安装grid时root.sh在二节点报错：

CRS-2676: Start of 'ora.cssd' on 'prodb2' succeeded
CRS-2672: Attempting to start 'ora.cluster_interconnect.haip' on 'prodb2'
CRS-2672: Attempting to start 'ora.ctssd' on 'prodb2'
CRS-2676: Start of 'ora.ctssd' on 'prodb2' succeeded
CRS-2676: Start of 'ora.cluster_interconnect.haip' on 'prodb2' succeeded
CRS-2672: Attempting to start 'ora.asm' on 'prodb2'
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/prodb2/crs/trace/ohasd_oraagent_grid.trc".
CRS-2883: Resource 'ora.asm' failed during Clusterware stack start.
CRS-4406: Oracle High Availability Services synchronous start failed.
CRS-4000: Command Start failed, or completed with errors.
2019/01/30 19:40:17 CLSRSC-117: Failed to start Oracle Clusterware stack

Died at /u01/app/12.2/grid/crs/install/crsinstall.pm line 914.
The command '/u01/app/12.2/grid/perl/bin/perl -I/u01/app/12.2/grid/perl/lib -I/u01/app/12.2/grid/crs/install /u01/app/12.2/grid/crs/install/rootcrs.pl ' execution failed

解决办法：

增加shm大小
#fsuser -km /dev/shm
#umount /dev/shm
#mount -t tmpfs -o mode=1777,nosuid,nodev,strictatime,size=XG tmpfs /dev/shm