[CentOS] Re: software raid

Sun Apr 1 12:15:43 UTC 2007
William Warren <hescominsoon at emmanuelcomputerconsulting.com>

if the hardware can hotswap then you should be ok if i am reading what 
les said correctly.

Les Mikesell wrote:
> Cen Tos wrote:
>> On 3/31/07, Scott Silva <ssilva at sgvwater.com> wrote:
>>> It is the breaking of electrical connections that it trips on. Even if a
>>> drive
>>> fails, it is still commected, and the system can ignore it. AFAIR you
>>> can't
>>> hot swap a regular SCSI drive either.
>> Does this mean I cannot hotswap a SATA drive in a software RAID array 
>> even
>> if I have it in a hotswap bay with a SATA hotswap backplane?
> Software raid has mdadm commands to fail/remove/add partitions, so it is 
> up to the hardware to be able recognize the new working drive.  There 
> are scsi-specific commands to remove and re-detect drives and 
> firewire/usb normally do it automatically (but not always the way you 
> expect).  I'm not sure how SATA fits into this picture.  If the service 
> is so critical that you can't run on the single mirror until a 
> convenient time to swap with a reboot you might want a hot spare so you 
> don't have worry about getting a new drive recognized with the machine 
> running.  Even if you didn't dedicate it to an array, if the spare drive 
> is in the machine you can easily partition it to match and add it with a 
> few commands.

My "Foundation" verse:
Isa 54:17  No weapon that is formed against thee shall prosper; and 
every tongue that shall rise against thee in judgment thou shalt 
condemn. This is the heritage of the servants of the LORD, and their 
righteousness is of me, saith the LORD.

-- carpe ductum -- "Grab the tape"
CDTT (Certified Duct Tape Technician)

Linux user #322099