Re: Switching from (deprecated) IDE driver -> SATA (PATA support)

[Justin Piszcz <jpiszcz@lucidpixels.com>]

On Sun, 25 Jan 2009, Justin Piszcz wrote:

>
>
> On Sun, 25 Jan 2009, Alan Cox wrote:
>
>> Easiest is to use labels. Old ide will keep hda,b,c,d constant
>> providing you have interfaces using the legacy IDE port mappings (0x1f0
>> and 0x170). Libata doesn't do that as pretty much every distribution had
>> already switched to volume labels, and the user space can do the job far
>> better than the kernel - especially as the newer devices with modern
>> interfaces don't have the old BIOS/DOS legacy ideas any more.
>> 
>> Mount by label also means you can flip back and forth between the
>> different drivers and kernel revisions.
>> 
>> Alan
>> 
>
> That works well with ext* filesystems as one can set it anytime with e2label 
> if I recall; however, how can one do this with XFS, is it possible without 
> booting off a boot-cd etc?
>
> Here is the filesystem information:
> p254:~# xfs_info /dev/sdd2
> meta-data=/dev/root              isize=256    agcount=16, agsize=1186676 blks
>         =                       sectsz=512   attr=0
> data     =                       bsize=4096   blocks=18986816, imaxpct=25
>         =                       sunit=0      swidth=0 blks
> naming   =version 2              bsize=4096 log      =internal 
> bsize=4096   blocks=9270, version=1
>         =                       sectsz=512   sunit=0 blks, lazy-count=0
> realtime =none                   extsz=65536  blocks=0, rtextents=0
>
> When I try to label it:
> p254:~# xfs_admin -L "root" /dev/sdd2
> xfs_admin: /dev/sdd2 contains a mounted filesystem
>
> fatal error -- couldn't initialize XFS library
>
> The label is currently not set:
> p254:~# xfs_admin -l  /dev/sdd2
> label = ""
> p254:~#
>
> I guess my next step is to try UUID?
>
>       Instead of giving the device explicitly, one may indicate the (ext2 
> or
>       xfs)  filesystem that is to be mounted by its UUID or volume label 
> (cf.
>       e2label(8) or  xfs_admin(8)),  writing  LABEL=<label>  or 
> UUID=<uuid>,
>       e.g.,   `LABEL=Boot'   or 
> `UUID=3e6be9de-8139-11d1-9106-a43f08d823a6'.
>       This will make the system more robust: adding or removing a  SCSI 
> disk
>       changes the disk device name but not the filesystem volume label.
>
> p254:~# xfs_admin -U generate /dev/sdd2
> xfs_admin: /dev/sdd2 contains a mounted filesystem
>
> fatal error -- couldn't initialize XFS library
> p254:~#
>
> Hmm, am I out of luck?
>
> Justin.
>

It comes with one :)
# xfs_admin -u  /dev/sdd2
UUID = 77ae4251-631f-4656-a365-c5723f5c5da8

Will try to use this to boot; however, I'd prefer the labels over the 
UUID, wish there was an easy way to set it.

Justin.