RAID or several .fdb files?

Hello all. I need an advice from experienced people. We are installing new hardware server with three IBM SCSI HDDs, 36 GB capacity each one. Total database size will be something about 100GB. The question is: which way of database deployment is more effective (stable, reliable), create one RAID array on these three HDDS (and put Navision database there) or create one Navision database containing three database files (usually with .fdb extension), one file per disk? Navision: Attain 3.01, OS : Windows 2000 Server. Thanks in advance. With best regards, Maxim

I would say that one database divided to 3 HDD’s will improve performance 3 times. Also I would suggest maximum size of database per HDD to be 5GB. I don’t remember where max size of db can be 2GB.

You will find plenty of excellent information on this topic in the forum archives [;)] In short: Ideally, you would split the database into several .fdb-Files and put each file on a mirrored RAID volume of its own (is that RAID 0 or 1? I always forget…). With this configuration, the RAID only adds to data security, while performance is achieved by Navision’s internal “software striping” (and, of course, by the increased bandwidth of the separately accessed disk volumes).

Arthur, our business is a retail trade, and such database size is usual for us. Are there any suggestions about RAID5 in this situation? Sorry, I should mention RAID5 in my first post. Thanks in advance. With best regards, Maxim

RAID1 improves performance only in read transactions but it’s best solutions if creating of .fbk files every night is not acceptable. RAID0 is for excelent performance if you backup data on your own.

RAID5 is most used cause it’s optimal solution in security&money. But it’s slower in write transactions than simple HDD. If u need extra security u can use RAID5+1 (RAID5 with RAID1). Also RAID0+1 is possible.

Max, Don’t use RAID 5 with the native navision database, it causes serious performance problems. Microsoft’s advice is to use RAID 1. Spreading your database over multiple hd’s is always a good idea.

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Originally posted by MarcoV
Max, Don’t use RAID 5 with the native navision database, it causes serious performance problems. Microsoft’s advice is to use RAID 1.


Hmmmm … can anybody tell me, where´s the risk using a RAID5 system? In our company we´re using a RAID5 system with an ULTRA160 cache (128 MB) controller (ICP Vortex) and it works like a snap. In most cases write operations only transmit a relatively small amount of data that is cached by the controller so it doesn´t matter that the physical write takes a little bit more time. Has anybody really tested how much difference it makes operating a let´s say 30 GB database in a single file on a single HDD or divided in thee files on three HDDs? Would be interested to read the results. Regards Alarich

With current technology, performance these days is not so much an issue. Still there is not a single question of the fact that RAID 5 on Navision is much slower, and definitely very risky.

To answer Alarich’s question, Both Compaq and Siemens Nixdorf did extensive testing to show the issues with RAID 5. The white papers should be available from your NSC.

Hi all, just a question, maybe silly, forgive me as I’m new at the Navision world: when you say that it is good to split the native data base into several .fdb files, are you meaning to split it into different “logical” volumes or into different “physical” disks? In other words, if I have just one (mirrored) disk, is it good to split it into …so to say… 4 volumes and then split the database into those 4 volumes even if the disk is however one? bye, Marco

No, it must be physical drives, spliting the database into multiple files on teh same physical drive wil slow it down.

Feels like we have discussed this before…

Many tahanks, David. Just another question, if you can… 1) I have two mirrored disks on my server. In (C:) I have installed the O.S. and NAV server. In (D:) I have just the database. What do you think it would be better: splitting the database in two (C & D, with one half “disturbed” by the O.S.) or leaving it as it is on D:? (consider that at the moment I have no problems of space as the database is 2GB, 50% occupied, and that the Server is dedicated to Navision only) bye, and thanks again Marco

Marco, Since you’re database is 2 gigs or less… leave it on D:. You should start thinking about splitting up your database when it exceeds 2 gigs, but still I would add some extra harddisks and wouldn’t store it on my system disk. It’s always smart to have a dedicated Navision server by the way.

I am currenly running my database on a raid 5 and it is approaching 4 gigs in size. what should i do to migrate this to multi disk and multi file setup

Take a backup with the Navision Client. Rebuild Your RAID to RAID-1. Then create a new empty database of lets say 1000Kb. Immidiately after that You expand the database so that You use one file on each physical drive. You do this by pressing the “Advanced” button in the “Expand database” dialog. Let’s say You have 20 users. Then I would build up my RAID-1 with 6 disks. First pair for C: and D:. OS on C: and executables on D:. E: on second pair and F: on third pair. Put database files on E: and F:. If You need more space/performance You put in mor disk and expand the database over the new disks.

1/ Create a backup. 2/ Reconfigure the Database Drives to RAID1 3/ Install the OS and Navision server program on a drive. (e.g. C:); 4/ Install the database split over 2 logic drives (e.g. G: and H:) Ensure that each drive for the database is made up of individual physical drives. You can do this with 5 drives if you do not want redundancy on the OS.

About the 2 Gig: isn’t that the old > 2.01 maximum size of a datbase part? I remember having to split up databases in parts of max 2 gig in these and earlier versions…

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About the 2 Gig: isn’t that the old > 2.01 maximum size


Yes. That limitation does not exist any more, but it’s wasn’t such a bad limitation (as long as You didn’t have big databases), since it forced You to buy more disk instead of expanding on the same disks. More disk = more performance