--- Manish Verma <[EMAIL PROTECTED]> wrote:
> i would like to add few more points while designing a NAS solution > > 1.writing of data on to HDD should be fast enough, at time when you > are > mounting central storage on multiple server the concurrent NFS > operation > makes it very difficult and the write on the box slows down e.g > netapp uses > wafl filesystem (or for that matter all NAS storage uses the same way > of > writing through cache) which does the writing of data from cache. > Your > solution should be based on using the cache to the maximum for both > read and > write. I have seen xfs,ext3 going down in the load condition. I guess corporate customers would like SCSI disks, even home users shouldnt go for anything less than SATA disks. I do recall NFS having lad issues that definitely needs to be looked into. Guess we will have to develop a proper set of test cases based on your feedback :). > 2. You will have to check the boot time of your NAS box and it should > be > under control there are NAS boxes ( i would not put the name here, > but you > can easily find it out) which takes 15-20 minutes to boot. The box > should be > able to boot in 3-4 minutes even if it a abnormal reboot. I have used pretty simple installations of LVM over RAID5 on Fedora Core 3 and it did come up in a few min. I do agree complex LVM and RAID installations need to be tested. > 3.you should benchmark your NFS box for NFS operation not I/O > operation on > disk. You may get good I/O on disk but may not be able to get good > NFS > operation. > > 4.The redundancy of storage array should not be limited to RAID5 > because now > the storage capacity of individual disks are going high (500GB SATA, > 300GB > SCSI and FCAL are in the market) you should be able to handle dual > disk > failure in the same RAID group lets say you have 14 disk RAID group > and your > one disk failed and rebuilding is going on (which will take some time > as the > capacity is more) and during that time if your second disk also fails > then > your whole of the RAID volume will go offline, you should have dual > parity > kind of solution. Well isnt the concept of spare disks in RAID meant for these purposes ? > 5.NAS solution should be modular i.e i should be able to add storage > and > processing both e.g if i am handling n NFS operation using one NAS > header > today with NTB storage and tomorrow if i want to increase my NFS > operation i > should be able to add more processing (NAS header to the same > storage) and > lets say i don't want to increase the NFS operation but i want to add > more > storage i should be able to do that as well and that too "on the fly" > because if my box is in production i cant shut it down. Adding disks would be limited by the enclosure holding them. A highly modular system I am afraid wont be there in a first cut we would probably have to set up a research lab or something where CPU and hard disks both are modular and are being used efficiently. Also if I add a CPU does it contribute to a existing box or creates a new box. There are various degrees of modularity which could be achieved but definitely not everything in the first version. > May be there are other things also can be considered and included but that is all i could put down off hand. > > When ever you are ready with your NAS solution i could be a good > customer Haha as soon as I get someone interested in coughing up resources you can be the beta tester. Unless ofcourse you have some spare cash and the knowhow to make cabinets suitable for housing hard disks with proper cooling. I wonder how temperature could be measured in the cabinet over a period of time - anyone has any thoughts on the same ? > for you :). also read on onstor while designing the solution. Mithun __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com _______________________________________________ ilugd mailinglist -- [email protected] http://frodo.hserus.net/mailman/listinfo/ilugd Archives at: http://news.gmane.org/gmane.user-groups.linux.delhi http://www.mail-archive.com/[email protected]/
