If you are running DAOS, you know that Transaction Logging is a prerequisite to enable DAOS on your server. Ever wondered what would happen if you turned Transaction Logging off? I tried it, and am actually really pleased with how this was implemented.
When you go in to your server document and change Transaction Logging to Disabled, when you save the document you get this warning:
and then when you say OK you get this:
What is happening here is any new attachments will now be stored in the NSF file, instead of the DAOS store (obviously losing any DAOS benefits), but the key is that any attachments already stored in the DAOS store will continue to work just fine, when a document is accessed the associated attachment will be there as it was when Transaction Logging was enabled.
I am of course not suggesting that you go try this on your production servers, but it is nice to see that there is some resiliency built in to DAOS, and should anything go wrong with your Transaction Logs, DAOS will keep serving up attachments.
After transaction logging is re-enabled attachments will automatically go back to being stored in the DAOS store, however you will have to run a Compact –c on all databases to get the attachments that were stored in the NSF while Transaction Logging was disabled moved to DAOS.
If by some chance you have not yet looked at DAOS, you might want to grab the DAOS Estimator tool and start calculating your potential disk savings, and don’t forget the impact DAOS can have on your backups as well.
Newly updated Technote 1415556 A checklist for implementing DAOS. If you are thinking about implementing DAOS or even if you have already implemented successfully, this is an excellent resource you should check out. The technote contains links to: – Required Fixpacks – Downloading and Using the DAOS Estimator – How to disable shared mail (as if anyone is actually using it) – NLO Encryption issues – Backup considerations – Transactions Logging – Upgrading ODS Versions – Compression Settings.
I have been running the DAOS estimator for a while on my production servers, a lengthy process when your mail file has 6000+ mail files, but hey it is worth it when you look at a potential to save a couple of Terabyte…. yes you read that correctly saving a couple of Terabytes by enabling DAOS.
We have a quasi production server in other words  it is my mail server and gets upgraded rather frequently (it is currently running 8.5 IF5, but with this issue behind us is likely to be running an 8.5.1 build shortly). When attempting to set up DAOS on the server we ran in to the following error in the log The database /lotus/domino/data/mail/xxxxxxxxx.TMP was unable to write to file /DAOS/0001/F0CEB8D561FA1F89852575F20069C85F47F0CEB8D561FA1P.nlo: File cannot be created We checked known issues, checked with some folks who had a little more DAOS experience, and with IBM… no one had seen this issue.
Interestingly enough if we manually created the 0001 directory DAOS would then enable just fine and create all the .NLO files, an easy solution though it left us wondering what would happen when the 0001 directory had 1000 objects and the 0002 directory had to be created.
First the solution, then the suspected cause.
1. Disable DAOS for all mail files (l compact mailxxxx.nsf -c -daos off)
2. Shut down Domino
3. Remove all DAOS directories
4. Remofe daoscat.nsf and daos.cfg from the Notes Data directory
5. Restart Domino
6. Enable DAOS for a mail file to test (l compact mailxxxx.nsf -c -daos on)
The suspected problem This particular server is running on AIX, we suspect that when DAOS was first enabled the UNIX ID which owned the server did not have permission to create files in the DAOS file system (we had a dedicated file system created for DAOS did not put in under the Notes Data directory), however the DAOS Catalog believed the 0001 directory had been created even though it had not, so even after the permission issues were resolved DAOS would not enable properly for us until we followed the process detailed above). So a word to the wise when creating you DAOS file systems double check those permission’s before enabling DAOS. Â We are still working with IBM to create an SPR to give some better error messages when DAOS fails to create a directory or file. Attachment consolidation (DAOS) — TroubleshootingDAOS Manager Tell commands
