mirroring over networking

[Apollon Koutlides]

> Kata tin tapeini mou gnomi einai kalytera oti mporeis na to lyseis me 
> hardware anti tou software na to lyneis etsi giati mporei men to 
> hardware na sou kostisei parapano alla yparxei kalytero apotelesma.

Kammia antirrhsh, if (kalytero_apotelesma == transfer_rate ||
                      cpu_overhead) {}  /* !C */

>  allo enas Raid controller pou an sou varesei o diskos apla ton vgazeis 
> kai prostheteis enan allo kainourio sti thesi tou kai kanei to 
> replication o controller kai allo einai na paideyesai me software RAID 
> ktl ktl.

Kai sto s/w RAID den einai toso diaforetika... to rebuild ginetai sto
background, aytomata (rebuild status/progress : cat /dev/md0)
Fysika, to s/w RAID exei kai to sobarotato pleonekthma oti mporei na
ylopoih8ei me fthnoys ATA-* diskoys (Redundant Array Of Inexpensive
Disks my a$$ me ta SCSIa).

>  To exo dokimasei se non production servers gia na do ti kai pos kai den 
> mou arese katholou. Tora gia home use ennoeitai o den tha dosei kaneis 
> ena skasmo lefta gia na parei RAID controller syn to kostos ton hot 
> plugable diskon kai tha kanei software raid.

Edw kai 3 mhnes trexw s/w RAID 5 (apo s/w RAID 1 epi 4 mhnes prin) se
(not so heavy) production environment kai anamfibola 8a hmoyn pseyths 
an elega oti exw opoiodhpote parapono. Mporei na mhn einai hot-
pluggable oi diskoi, alla to systhma trexei me psofio disko (se 
degraded mode fysika, ektos an exeis hot spare opote karfaki poy
toy kahke) arkei na exeis mono ena disko per channel. (O slave diskos
8a arnh8ei na synergastei an de doyleyei o master, you can't have it
all)

Fysika, milaw gia local RAID kai se kammia periptwsh RAID over network
(diestrammeno moy akoygetai... mallon 8a to dokimasw syntoma! :)

>  To LVM den to exo dei katholou opote den mporo na eikfero gnomi gia to 
> olo thema.

Same here. ;)

>  Filika
>   Stamatis

A'flakia

Apollon Koutlides