Re: [HELP] RAID chunk-size - alternatives

2002-04-05 Thread Russell Coker
On Fri, 5 Apr 2002 12:25, Anthony DeRobertis wrote: > > Of course. As we all know SCSI cables never break. There must > > be something > > about the IDE command-set which causes copper wires to corrode. :-# > > (I know this is a joke, but) actually there is. IDE has a > wonderful feature of only

Re: [HELP] RAID chunk-size - alternatives

2002-04-05 Thread Anthony DeRobertis
On Friday, April 5, 2002, at 03:34 AM, Russell Coker wrote: Of course. As we all know SCSI cables never break. There must be something about the IDE command-set which causes copper wires to corrode. :-# (I know this is a joke, but) actually there is. IDE has a wonderful feature of only t

Re: [HELP] RAID chunk-size - alternatives

2002-04-05 Thread Russell Coker
On Fri, 5 Apr 2002 10:27, Anthony DeRobertis wrote: > On Tuesday, April 2, 2002, at 06:22 PM, Russell Coker wrote: > > Another thing, you should have a separate cable for each disk > > you want to be > > independant. So for RAID-1 you should have two cables so that a cable > > failure won't lose y

Re: [HELP] RAID chunk-size - alternatives

2002-04-05 Thread Anthony DeRobertis
On Tuesday, April 2, 2002, at 06:22 PM, Russell Coker wrote: Another thing, you should have a separate cable for each disk you want to be independant. So for RAID-1 you should have two cables so that a cable failure won't lose your data. For a RAID-5 with 5 disks you want 5 cables. This d

Re: [HELP] RAID chunk-size - alternatives

2002-04-02 Thread Alvin Oga
hi ya dave ypppers on your comments... another major point... - raid protects aginst disk failure ... but if raid wont come back online ... ( not mountable ) ... you lose all data ... -->> make sure your data is backed elsewhere and tested On Tue, 2 Apr 2002, Dave Sherohm

Re: [HELP] RAID chunk-size - alternatives

2002-04-02 Thread Russell Coker
On Wed, 3 Apr 2002 01:15, Dave Sherohman wrote: > Don't know where you got the "typically 5 disks" bit from. RAID5 > costs you one drive's worth of capacity. Also, if I were to set up a > 5-disk RAID5 for critical data, I'd go with 4 active disks, plus one > spare. I've noticed that 5 disks seem

Re: [HELP] RAID chunk-size - alternatives

2002-04-02 Thread Russell Coker
On Wed, 3 Apr 2002 00:29, Alvin Oga wrote: > > Chunk size does not matter for RAID-1, but does matter for other RAID > > levels. > > humm ..thought was the otehr way ... time for me to go look at some > raid source code i suppose .. when time permits The chunk size determines physical location of

Re: [HELP] RAID chunk-size - alternatives

2002-04-02 Thread Dave Sherohman
Since I'm feeling bored at the moment... On Tue, Apr 02, 2002 at 02:29:28PM -0800, Alvin Oga wrote: > typically a minimum of 2 disks used for raid0 or raid1... > raid1(mirroring) protects against one disk failure > ( one disk's capacity is used as a redundant copy and not for user) >

Re: [HELP] RAID chunk-size - alternatives

2002-04-02 Thread Alvin Oga
hi ya russell On Tue, 2 Apr 2002, Russell Coker wrote: > On Tue, 2 Apr 2002 13:48, Alvin Oga wrote: > > chunk size does NOT matter for raid5... > > Chunk size does not matter for RAID-1, but does matter for other RAID levels. humm ..thought was the otehr way ... time for me to go look at some

Re: [HELP] RAID chunk-size

2002-04-02 Thread Russell Coker
On Tue, 2 Apr 2002 13:48, Alvin Oga wrote: > chunk size does NOT matter for raid5... Chunk size does not matter for RAID-1, but does matter for other RAID levels. > if your disk was partitioned as... 2K bytes/inode... You probably mean 2K blocks. The number of bytes per inode just determines t

Re: [HELP] RAID chunk-size

2002-04-02 Thread Alvin Oga
hi ya chunk size does NOT matter for raid5... if your disk was partitioned as... 2K bytes/inode... chunksize of 32 will allow you to write 64K of data in one "chunk" to disks chunksize of 128 will allow you to write 256K of data in one "chunk" to disks...