You do not need to manually manage the log shipping backup files, they are managed by the log shipping system stored procedures and the agent jobs.
Personally i would recommend that you do not manually trim files from the primary and secondary locations as, if they are trimmed too soon you will likely break your log shipping scenario.
The following will show the retention periods in use currently
backup_retention_period column from
exec sys.sp_help_log_shipping_primary_database
@database = 'yourprimarydb'
file_retention_period column from
exec sys.sp_help_log_shipping_secondary_database
@secondary_database = 'yoursecondarydb'
the following will set the retention periods to the values specified
for the primary
exec sys.sp_change_log_shipping_primary_database
@database = 'yourprimarydb'
, @backup_retention_period = numberofminutes
for the secondary
exec sys.sp_change_log_shipping_secondary_primary
@primary_server = 'primary_server',
@primary_database = 'primary_database',
@file_retention_period = numberofminutes
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"Ya can't make an omelette without breaking just a few eggs" 😉