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PesmergaFlag for Greece

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Deletion of logs on Exchange 2007

I have a quick question, hereI come: Will I have any functionality problem on my MS Exchange Server 2007 if i delete all the log files from the same folder where my primary edb is stored, like C:\Program Files\Microsoft\Exchange Server\Mailbox\MyStandbyStorageGroup/*.log ?
Thank you
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Jacobh06
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They are only .log files and you should have no issues deleting them.
May I ask why you want to delete them? They don't take up much space.
Thanks and I am glad to assist.
~Jake
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Firstly, I just thought that as you have problem if you delete the sql log files, it was possibly to have something similar on exchange.
Secondly, I am talking about a server which I don't manage but they called me today to fix a issue where they can't receive mails form the outside. It seems that its hard disk has 2 GB free and I have on the event viewer errors with ID 15006: "The Microsoft Exchange Transport service is rejecting message submissions because the available disk space has dropped below the configured threshold."

Thank you
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Mestha
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Take a look here: http://support.microsoft.com/kb/240145
You are able to delete transaction logs, you just have to do it in the proper manner.
~Jake
I AGREE WITH Mestha...................pls  NEVER NEVER NEVER delete any files in Exchange........
These are not plain log files these are actual transaction logs on which you database stays mounted & mail flow works for the users connected to exchange server......

If the database is mounted & mail-flow is working then go ahead take a backup of the information stores using the NTBACKUP if Exchange 2007 server is installed on a Windows 2003 server operating system..
If you really do not want the log files Take the Full backup ..
Removing the logs in a controlled manner is different to telling someone they can just delete the logs.

However what should be looked at is why the logs are building up. If a backup is being taken then is it Exchange aware? If it is, then the logs should be flushed out.

Back pressure can be a problem. If you have more storage on the server elsewhere then you can move either the transaction logs or the database elsewhere. It is actually best practise to have the transaction logs and the database on separate disks/arrays if possible.

Simon.
WHY TRANSACTION LOGS ARE IMPORTANT
===================================
One of the most important components of Exchange server is the transaction logs. Exchange server was designed to write all transactions to these log files and commit the changes to the databases when the system allows. Users can send and receive messages without touching the database thanks to this write-ahead method of logging.

When a message is sent, the transaction is first recorded in the transaction logs. Until the transaction is committed to the Exchange database (EDB), the only existence of this data is in the system memory and the transaction logs. In the event of a crash, you lose the contents of the memory and all you are left with is the record in the transaction log. These transaction logs are crucial to the recovery of a failed Exchange server, whether it was a minor crash that required a reboot, or a more catastrophic failure requiring the deployment of your disaster recovery plans. The same goes for other transactions such as received messages, deleted items and messages moved to different folders.

For this reason, it is recommended to house the transaction files on a redundant storage system, like a RAID 1 array, so that in the event of a hardware failure, no data is lost. Losing a set of transaction logs will not prevent you from restoring from your backups, but you will lose all the messages and changes since the last full backup.
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That link will also provide you with ways to prevent this from happening in the future.
~Jake
This is an Exchange on a remote site of my company, several kilometers away, plus that they are all off from work there. So I'm stacked up with the server with only a 80 GB hard disk (2 GB free) and a network place for me with 70 GB free.I'm trying now a ntbackup to this place taking only the exchange bases backup
Event ID 15006 surely gives an explaination of the lack of free disk space & hence mails are not received from internet.....

Check Add/Remove programs to remove any unwanted programs to create free disk-space....
If you are backing up the Exchange databases, then that should be flushing out the transaction logs correctly.

When was the last full backup taken? If you look at the Properties of the database under EMC, Server Config, Mailbox, then you will see a date that the last full backup completed. It may well be that the backup hasn't run.

You can enable circular logging to stop Exchange from retaining and transaction logs, but that means you have no recovery methods in the event of a storage failure. The most you would be able to do is go back to the last backup.

An 80gb drive is very small, and is just about on the limit of what I would put in to a test server - certainly not production.

Simon.
I agree with you about the disk space, but they don't give me any hardware. The remote access is enough :P  Anyways, I'm just hoping that the backup will flush them. Will the backup which is not full and takes only the exchange part, flush them?
To flush it must be a full backup. A copy or incremental will not flush the logs.

Simon.
Thank you all
Thank you all folks :)