This post will show you how to monitor free log space in SQL Server.
Method 1: Using SQLPERF
DBCC SQLPERF ('LOGSPACE')
GO
Method 2: sys.dm_db_log_space_usage
SELECT total_log_size_in_bytes*1.0/1024/1024 total_log_size_in_MB,
used_log_space_in_bytes*1.0/1024/1024 used_log_space_in_MB,
(total_log_size_in_bytes - used_log_space_in_bytes)*1.0/1024/1024
AS free_log_space_in_MB
FROM sys.dm_db_log_space_usage;
Method 1: Using SQLPERF
DBCC SQLPERF ('LOGSPACE')
GO
Method 2: sys.dm_db_log_space_usage
SELECT total_log_size_in_bytes*1.0/1024/1024 total_log_size_in_MB,
used_log_space_in_bytes*1.0/1024/1024 used_log_space_in_MB,
(total_log_size_in_bytes - used_log_space_in_bytes)*1.0/1024/1024
AS free_log_space_in_MB
FROM sys.dm_db_log_space_usage;