On Fri, 2003-06-20 at 21:48, Mithun Bhattacharya wrote: > > --- "Jasmeet S. Virdi" <[EMAIL PROTECTED]> wrote: > > Hi all, > > Hope to get some antennas twitching this time .. I think someone > > talked about RAID 1 on the list sometime back. I want to understand > > the > > best practices and how to go about doing it. Ne pointers ... > > Linear : no redundancy - preferred where data redundancy is not > required and multiple physical disks need to me merged to create a > single large partition. > RAID0 : no redundancy - preferred where data redundancy data is split > into small chunks and spread uniformly over the complete device - > possible use might be a replicated database since throughput is maximum > in this.
If no redundancy is there, then what data redundacy you talking about in RAID0. > RAID1 : Data on one disk is mirrored completely onto another. Requires > equal sized disks or the device will provide disk space equal to the > smaller of the two disks. Fast throughput with redundancy - can survive > one disk failure. Highest throughput of all redundancy enabled RAID > system. > RAID4 : Parity for n-1 disks is calculated and stored on the remaining > disk Most optimum usage of disk space but also the slowest of all the > RAID systems. Equal sized disks required as in RAID1. > RAID5 : Parity calculated as in RAID4 but data is striped across the > device. Optimum usage of disk space speed enhanced appreciably due to > striping. Recommended where many small sized disks are available and > throughput is important but not of highest importance. Equal sized > disks required. > > In a production environment hardware RAID cards are preferred since it > removes a layer of overhead from the kernel. > Database servers are preferably not kept on RAID devices or if needed > then on RAID0. RAID5 is best kept for internal servers. If less that 3 > disks are being used to create a RAID device go for RAID1 since parity > calculation has a overhead of its own. > /boot can be on a software Linear or a RAID1 device. For all other > software RAID devices /boot needs to exist on a non software RAID > device. > > As for how to go about doing it RedHat allows you to setup RAID1 and > RAID5 during installation. For other complex scenarios the Software > RAID HOWTO is best read end to end :). > > > Mithun > regards, -Yash > __________________________________ > Do you Yahoo!? > SBC Yahoo! DSL - Now only $29.95 per month! > http://sbc.yahoo.com > > _______________________________________________ > ilugd mailing list > [EMAIL PROTECTED] > http://frodo.hserus.net/mailman/listinfo/ilugd > _______________________________________________ ilugd mailing list [EMAIL PROTECTED] http://frodo.hserus.net/mailman/listinfo/ilugd
