FC3 mdadm issue

Aaron M. Hirsch aaronh at uptime.net
Fri Dec 3 17:38:43 UTC 2004


On Fri, 2004-12-03 at 16:34 +0000, Robin Bowes wrote:

> Aaron M. Hirsch wrote:
> > I created md0-3 during boot and now want to create another raid device 
> > which would be md4.  I've gone through the man page and searched online 
> > but am coming up blanks for an answer.  I am using FC3 x86_64...
> > 
> > To create the new raid device I ran:  mdadm --create /dev/md4 --level=0 
> > --raid-disks=2 /dev/hda6 /dev/hdc6 which errors out stating: mdadm: 
> > error opening /dev/md4: No such file or directory.  Of course it's not 
> > there yet, I'm just now trying to create it.
> 
> I ran into this yesterday.
> 
> You have two options:
> 
> 1. From Luca Berra: "you could use the --auto= option of mdadm to have 
> it create the device for you, the only issue with that is that mdadm 
> will use the first free minor numbr it finds instead of using the minor 
> implied by the device name. (i was planning on changing that behaviour 
> sooner or later)."
> 
> 2. Use mknod to create the device before creating the array. Here's what 
> I did to create /dev/md2:
> 
> # [root at dude dev]# mknod --help
> Usage: mknod [OPTION]... NAME TYPE [MAJOR MINOR]
> Create the special file NAME of the given TYPE.
> 
>    -Z, --context=CONTEXT   set security context (quoted string)
> Mandatory arguments to long options are mandatory for short options too.
>    -m, --mode=MODE   set permission mode (as in chmod), not a=rw - umask
>        --help     display this help and exit
>        --version  output version information and exit
> 
> Both MAJOR and MINOR must be specified when TYPE is b, c, or u, and they
> must be omitted when TYPE is p.  If MAJOR or MINOR begins with 0x or 0X,
> it is interpreted as hexadecimal; otherwise, if it begins with 0, as octal;
> otherwise, as decimal.  TYPE may be:
> 
>    b      create a block (buffered) special file
>    c, u   create a character (unbuffered) special file
>    p      create a FIFO
> 
> Report bugs to <bug-coreutils at gnu.org>.
> 
> [root at dude dev]# file /dev/md1
> /dev/md1: block special (9/1)
> [root at dude dev]# file /dev/md0
> /dev/md0: block special (9/0)
> [root at dude dev]# file /dev/md5
> /dev/md5: block special (9/5)
> [root at dude dev]# mknod /dev/md2 b 9 2
> [root at dude dev]# ls /dev/md2
> /dev/md2
> 
> Done!
> 
> (If you don't have the array set to auto-start, you'll have to add the 
> "mknod" command to your system startup scripts before trying to start 
> the array directly)
> 
> R.
> 


Thanks Robin!  This is exactly what I was looking for!  
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://listman.redhat.com/archives/fedora-list/attachments/20041203/195e0b06/attachment-0001.htm>


More information about the fedora-list mailing list