zfs: affected by geom_(mbr|bsd) => geom_part_(mbr|bsd) ?

[Andriy Gapon]

Very belated but somebody reading archives might find this useful.
Only today I discovered zdb command and its -C option:

$ zdb -C
tank
    version=6
    name='tank'
    state=0
    txg=1997530
    pool_guid=15723282379537418671
    hostid=714261228
    hostname=''
    vdev_tree
        type='root'
        id=0
        guid=15723282379537418671
        children[0]
                type='disk'
                id=0
                guid=1732303387090405178
                path='/dev/ad6s2d'
                devid='ad:GEA534RF0TK35A'
                whole_disk=0
                metaslab_array=14
                metaslab_shift=32
                ashift=9
                asize=493659881472
                DTL=182


on 18/11/2008 19:29 Andriy Gapon said the following:
> I just remembered that I saved old zpool.cache file before "migrating"
> the pool.
> I looked at the diff of hexdumps and there are a number of differences,
> it's hard to understand them because the file is binary (actually it
> seems to contain serialized name-value pairs), but one difference is
> prominent:
> ...
>  00000260  64 65 76 69 64 00 00 00  00 00 00 09 00 00 00 01
> |devid...........|
> ...
> -00000270  00 00 00 15 61 64 3a 47  45 41 35 33 34 52 46 30
> |....ad:GEA534RF0|
> -00000280  54 4b 33 35 41 73 31 73  33 00 00 00 00 00 00 28
> |TK35As1s3......(|
> ...
> +00000270  00 00 00 11 61 64 3a 47  45 41 35 33 34 52 46 30
> |....ad:GEA534RF0|
> +00000280  54 4b 33 35 41 00 00 00  00 00 00 28 00 00 00 28
> |TK35A......(...(|
> ...
> 
> It looks like old "devid" value is "ad:GEA534RF0TK35As1s3" and new one
> is "ad:GEA534RF0TK35A". Just a reminder: actual zpool device is ad6s2d.
> 
> The new value is what is reported by diskinfo:
> $ diskinfo -v ad6
> ad6
> ...
>         ad:GEA534RF0TK35A       # Disk ident.
> 
> $ diskinfo -v ad6s2
> ad6s2
> ...
>         ad:GEA534RF0TK35A       # Disk ident.
> 
> $ diskinfo -v ad6s2d
> ad6s2d
> ...
>         ad:GEA534RF0TK35A       # Disk ident.
> 
> Hmm, "indent" is reported to be the same for all three entities.
> 
> I don't remember what diskinfo reported with pre-gpart kernel, but I
> suspect that it was something different.
> Could anybody please check this? (on 7.X machine without GEOM_PART).
> 
> I quickly glimpsed through sources and it seems that this comes from
> DIOCGIDENT GEOM ioctl i.e. "GEOM::ident" attribute. It seems that
> geom_slice.c code has some special handling for that.
> 


-- 
Andriy Gapon