ORA-01033: Solution for ORACLE initializing or disabling

Today with the client to connect to oracle, found to report ORA-01033: ORACLE is initializing or closing the error, in fact, this error reported for a few days, the first two restart just fine, why can't I get up today? By searching on the Internet, it's a good solution,
First, I use the startup mount command, which is normal. Then, if I use alter database open, an error is reported, as shown in figure

 

From this, we can see the problem of archiving files, and then

 

It can be seen that the reorganization is not in the current status but has been archived. Therefore, use the clear command to recreate the current group.
SQL> alter database clear logfile group 3;
If the log group has not been archived, use
SQL> alter database clear unarchived logfile group 3;
Then, the alter database open database can be connected.
I did this on my own machine, but if I had to back up it right away on the production machine.
Note:
1) if the damaged online log file is not the current one, you can rebuild the log file with only clear. However, if the database is archived but the log is not archived, you need to force clear.
2) clear is recommended, especially after forcible clear, for a full backup of the database.
3) This method is applicable to archive and non-archive databases.


Author's endless Neural Networks