If you find your Exchange transaction logs are taking up all the space on the drive, which if it fills up will cause a dismount of your Exchange DB and need to backup quick this can save you....
You can enable circular logging but unless you have good backups that is a horrible idea, but if yuou wish to this is how you do it:
PS C:\> get-mailboxdatabase DB01 | fl *path*
EdbFilePath : C:\ExchangeDatabases\DB01\db\DB01.edb
LogFolderPath : C:\ExchangeDatabases\DB01\logs
TemporaryDataFolderPath :
MetaCacheDatabaseVolumesRootFolderPath : C:\EDB\
MetaCacheDatabaseRootFolderPath : C:\EDB
MetaCacheDatabaseMountpointFolderPath : C:\EDB\DB01
MetaCacheDatabaseFolderPath : C:\EDB\DB01\DB01.mcdb
MetaCacheDatabaseFilePath : C:\EDB\DB01\DB01.mcdb\DB01-mcdb.edb
PS C:\> Get-MailboxDatabase DB01 | select circ*
CircularLoggingEnabled
----------------------
False
PS C:\> Set-MailboxDatabase DB01 -CircularLoggingEnabled:$true
WARNING: Circular logging parameter change will not be applied on this database before it is remounted. Dismount and
remount database "DB01" in order to apply this parameter change.
PS C:\> Dismount-Database DB01 -Confirm:$false
PS C:\> Mount-Database DB01
This will tell the OS and Exchange the the DB and TL files have been backed up, which is the same process as doing a backup - ensure you actually have a full backup
PS C:\> diskshadow
Microsoft DiskShadow version 1.0
Copyright (C) 2013 Microsoft Corporation
On computer: BearMail, 07/07/2022 16:30:08
DISKSHADOW> add volume c:
DISKSHADOW> begin backup
DISKSHADOW> create
Alias VSS_SHADOW_1 for shadow ID {7a1ed4b2-518b-4ddf-9b5b-774cd15de41f} set as environment variable.
Alias VSS_SHADOW_SET for shadow set ID {122a1b8b-0830-4ebe-98f5-c29725341cd7} set as environment variable.
Querying all shadow copies with the shadow copy set ID {122a1b8b-0830-4ebe-98f5-c29725341cd7}
* Shadow copy ID = {7a1ed4b2-518b-4ddf-9b5b-774cd15de41f} %VSS_SHADOW_1%
- Shadow copy set: {122a1b8b-0830-4ebe-98f5-c29725341cd7} %VSS_SHADOW_SET%
- Original count of shadow copies = 1
- Original volume name: \\?\Volume{0020b24b-0000-0000-0000-602200000000}\ [C:\]
- Creation time: 22/04/2020 16:30:33
- Shadow copy device name: \\?\GLOBALROOT\Device\HarddiskVolumeShadowCopy1
- Originating machine: mailbear.serverbear.com
- Service machine: mailbear.serverbear.com
- Not exposed
- Provider ID: {b5946137-7b9f-4925-af80-51abd60b20d5}
- Attributes: Auto_Release Differential
Number of shadow copies listed: 1
DISKSHADOW> end backup
DISKSHADOW> exit
PS C:\>