Database not starting due to ORA 00205 error in identifying control file

Database not starting up due to ORA-00205 error in identifying control file

SQL> startup
ORACLE instance started.

Total System Global Area 2147483648 bytes
Fixed Size                  2085360 bytes
Variable Size            1040190992 bytes
Database Buffers         1090519040 bytes
Redo Buffers               14688256 bytes
ORA-00205: error in identifying control file, check alert log for more info

If you are getting above error during starting up database,

shutdown the database and check database datafiles and controlfiles file system mount option. 

sometime it is not mounted with nolock option  in mostly linux system. 

run mount command to check current mount option:

mount

If output is like below for FS which contains your datafiles 

xxxxxxxxxxxxxxxxxx:/vol/xxxxxxxxx01/oradata on /oradata type nfs (rw,hard,wsize=32768,rsize=32768,addr=10.20.16.52)

Check FSTAB file

cat /etc/fstab

take backup of fstab  file

sudo cp /etc/fstab /etc/fstab_bkp

change the same entry in fstab

 sudo vi /etc/fstab

edit the /etc/fstab file like below: 

xxxxxxxxxxxxxxxx:/vol/xxxxxxxxxxxxxxxxxoradata /oradata        nfs      rw,nolock,hard,wsize=32768,rsize=32768,actimeo=120,timeo=600,tcp   1 2

Aftet this,  unmount the /oradata FS

sudo umount /oradata

Remount the same:

sudo mount  xxxxxxxxxxxxxxxxxxx:/vol/xxxxxxxxxxxxxx/oradata /oradata

If it doesn't work then 

use mount the same Fs with below comand: 

mount the FS with proper mount option for nfs

sudo mount -t nfs -o rw,nolock,hard,wsize=32768,rsize=32768,actimeo=120,timeo=600,tcp fcgsnprdsng03b:/vol/gemdbval01/oradata /oradata

check again for mount option

 mount

if it looks good this time then 

start the database