ORA-01078: failure in processing system parameters ORA-01565: error inidentifying file '+DATA/ORCL/spfileorcl.ora' ORA-17503: ksfdopn:2 Failed to open file +DATA/ORCL/spfileorcl.ora ORA-01034: ORACLE not available ORA-27123: unable to attach to shared memory segment Linux-x86_64 Error: 13: Permission denied

There are many things for occur error:

ORA-01078: failure in processing system parameters 
ORA-01565: error inidentifying file '+DATA/ORCL/spfileorcl.ora'; 
ORA-17503: ksfdopn:2 Failed to open file +DATA/ORCL/spfileorcl.ora 
ORA-01034: ORACLE not available 
ORA-27123: unable to attach to shared memory segment 
Linux-x86_64 Error: 13: Permission denied

I write here often issues and their solutions:
first of all check permission on $ORACLE_HOME/bin/oracle file in both ASM and RDBMS home, this file is oracle executable file, there must be permission 6751 for this file. let me check

ls -l $ORACLE_HOME/bin/oracle
-rwxrwxrwx 1 oracle asmadmin /u01/app/oracle/product/11.2.0/dbhome_1/bin/oracle

change it with root user

chmod 6751 /u01/app/oracle/product/11.2.0/dbhome_1/bin/oracle

another often issue is that oracle user have not proper groups in operating system level, for normal work there must be this groups

[oracle@node1]$ id
uid=54321(oracle) gid=54321(oinstall) groups=54321(oinstall),54322(dba),54323(asmadmin),
54324(asmdba),54326(oper)

if they aren't then add oracle user in these groups with command

usermod -G usermod -G oinstall,dba,oper,asmdba,asmadmin oracle

if you have grid user also check for it, there must be groups shown below

[grid@node1]$ id
uid=54322(grid) gid=54321(oinstall) groups=54321(oinstall),54322(dba),54323(asmadmin),
54324(asmdba),54325(asmoper)

i hope this will usefull for you, because i spent many time for solve this error.
thank you.

ORA-01078: failure in processing system parameters ORA-29701: unable to connect to Cluster Synchronization Service

startup of ASM instance failed with error:
ORA-01078: failure in processing system parameters
ORA-29701: unable to connect to Cluster Synchronization Service

check services by command:

crs_stat -t
Name           Type           Target    State     Host        
------------------------------------------------------------
ora.DATA.dg    ora....up.type OFFLINE   OFFLINE      
ora....ER.lsnr ora....er.type ONLINE    ONLINE    oralnxt01   
ora....2C.lsnr ora....er.type ONLINE    ONLINE    oralnxt01   
ora.asm        ora.asm.type   OFFLINE   OFFLINE      
ora.cssd       ora.cssd.type  ONLINE    ONLINE    oralnxt01   
ora.diskmon    ora....on.type ONLINE    ONLINE    oralnxt01   
ora.orcl.db    ora....se.type OFFLINE   OFFLINE    

solution:
start services manually

crsctl start resource ora.cssd
CRS-2672: Attempting to start 'ora.cssd' on 'oralnxt01'
CRS-2679: Attempting to clean 'ora.diskmon' on 'oralnxt01'
CRS-2681: Clean of 'ora.diskmon' on 'oralnxt01' succeeded
CRS-2672: Attempting to start 'ora.diskmon' on 'oralnxt01'
CRS-2676: Start of 'ora.diskmon' on 'oralnxt01' succeeded
CRS-2676: Start of 'ora.cssd' on 'oralnxt01' succeeded

sqlplus / as sysasm

SQL*Plus: Release 11.2.0.1.0 Production on Fri Jan 25 10:25:56 2013

Copyright (c) 1982, 2009, Oracle.  All rights reserved.

Connected to an idle instance.

SQL> startup;
ASM instance started

Total System Global Area  283930624 bytes
Fixed Size                  2212656 bytes
Variable Size             256552144 bytes
ASM Cache                  25165824 bytes
ASM diskgroups mounted

that's all. enjoy :)