To shrink Log file you have to run following command.
DBCC SHRINKFILE ( ‘Database_log’ , NOTRUNCATE)
So here we used NOTRUNCATE option because in log shipping transaction log sequence important if you run the normal Shrink file or with truncate file option then log shipping will be failed.
So run Shrink File with NOTRUNCATE option. Although many DBA & Sql Server experts gave suggestion to avoid shrink Log file.
But we can do shrink file in log shipping with NOTRUNCATE option if database Log size too much large and you have space issue.