Hi @Sai ,
Backup operation will do not reduce the size of database files. You need to run DBCC ShrinkFile(logfile) command to reduce the size of log file.
If you do not backup log file regularly, your log file will grow rapidly.
You can follow below steps to shrink log file.
1.Use below T-SQL to check the size of log file, and the space used for log fie.
DBCC SQLPERF(LOGSPACE)
GO
2.Perform transaction log backup
sometimes, we have to perform multi transaction log backup before the transaction log could be shrank.
3.Shrink transaction log
DBCC SHRINKFILE(logfile)
If the transaction log cannot be shrank, please execute the following statement to check why the transaction log cannot be shrink:
SELECT log_reuse_wait_desc FROM sys.databases WHERE name='<database name>'
If the result is other than NOTHING, please perform corresponding operation. Then please try step 2 and 3 again.
4... Check the size of log file again.
DBCC SQLPERF(LOGSPACE)
GO
Refer to the blog Handling large log files and DBCC SHRINKFILE (Transact-SQL).
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