ORA-27104: system-defined limits for shared memory was misconfigured

I faced this error while trying to restore & recover of a PDB (pluggable database)
part of the log file and the solution is described here below:

log:
initialization parameters used for automatic instance:
db_name=CDB
db_unique_name=gbux_pitr_PDB1_CDB
compatible=12.1.0.2.0
db_block_size=8192
db_files=200
diagnostic_dest=/oracle/app/oracle
_system_trig_enabled=FALSE
sga_target=1888M
processes=200
db_create_file_dest=/oracle/auxilary
log_archive_dest_1='location=/oracle/auxilary'
enable_pluggable_database=true
_clone_one_pdb_recovery=true
#No auxiliary parameter file used


starting up automatic instance CDB

RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-03002: failure of recover command at 07/31/2016 16:22:20
RMAN-04014: startup failed: ORA-27104: system-defined limits for shared memory was misconfigured


Solution:
switch to root user and adjust these kernel parameter in /etc/sysctl.conf
to these values:

[root ~]# cat /etc/sysctl.conf  | grep kernel | grep -v "#"
kernel.sem = 250        32000   100     128
kernel.shmmax = 75161927680
kernel.shmmni = 4096
kernel.shmall = 18350080


good luck!