MAXDB log file how to recover, By mistake i deleted

[Former Member]

Hi all,

My SAP server was not opening means after starting from SAP Management Console it went to yellow state and then i read in blogs that LOG file is fulled thats why its not working make another one log file using MAXDB DBM after taking database back but how could i do this its size is 300GB, i couldnot make backup and log file got deleted. now what to do please help.

Please HELP...!!

[thorsten_zielke]

Can you clarify on how you deleted your Log Volumes? Are the physical log volume files still present, but the content has been deleted e.g. by a 'clear log' or did you indeed permanently delete all your Log Volumes on OS level?

The problem is that MaxDB needs Log Volumes to be able to start, even though the actual data is kept on the data volumes. A 'clear log' only works on existing log volumes, but does not recreate any missing Volumes (I hope we can change this in the future).

Do you have any file system backup available where you could extract the old Log Volumes from? If so, you could restore those Log Volumes and then perform a 'util_execute clear log' - it may work.

Thorsten

[Former Member]

Dear Thorsten,

Thank you so much for your reply.

1. Log file is deleted physically from OS level.

2. The database is of 300GB how to take a back up i dont have another 300 GB space to take back up.

3. now is there any other option, with out log file how can i start it. now the log file is deleted so in SAP Console now the status is as below.

4. How to make disp+work in running state..??? please tell me.

Thanks & Regards,

Manish Sharma

[thorsten_zielke]

Hi,

ok, if you are using at least MaxDB 7.7.02.06, version 7.8 or version 7.9, you can simply:

- bring the database to 'admin' state

- and then use dbmcli from the command line to recreate and format the log area with 'util_execute clear log'

You would loose any redo information kept on the log volumes, but as you deleted those volumes, there is nothing left to help you with that. However, if the database was stopped without any transactions left open, you would not loose anything. The 'undo' information is kept on the Data Volumes, which is good for you. Worst case would be a long running transaction which could not be redone because of the missing log info.

Keep in ming to start a full data backup afterwards, because this is mandatory to be able to perform log backups.

If you are using MaxDB 7.6, please try to go to 'admin' state and perform a full backup (make space for that backup, there is no other option besides manual patching the log volume). Then, recover your database using that backup with the option to initialize the database, that is all data and log volumes are formatted before the recovery starts.

Thorsten

[Former Member]

Dear Thorsten,

Greeting of the day.

Actually  i dont have back up, but i got a log file that is not from my system, from some other system i got that log file (contains inside the logs for any other system).

now is it possible to start my sap server with that log file(after clearing the log or any other option).

Thanks & Regards,

Manish Sharma