Cannot setup dumpdev on glabel disk

[Samuel Chow]

On 8/31/2018 1:46 PM, Samuel Chow wrote:
> On 8/31/2018 1:21 PM, Mark Johnston wrote:
>> On Sat, Sep 01, 2018 at 02:09:12AM +0700, Eugene Grosbein wrote:
>>> 31.08.2018 23:08, Samuel Chow wrote:
>>>
>>>> I am running 11-STABLE, and I am experiencing kernel panics when I 
>>>> am destroying a VIMAGE-based jail. Naturally, I flipped to the 
>>>> chapter about 'Kernel Debugging' to learn about 'Obtaining a Kernel 
>>>> Crash Dump'.
>>>>
>>>> However, I am finding that my permanently glabel'ed disk partition 
>>>> cannot be used as dumpdev. Is that true, and why not? I mean, swap 
>>>> can use it just fine. I am unable to find this restriction in the 
>>>> documentation.
>>>>
>>>>
>>>> # grep swap /etc/fstab
>>>> /dev/label/boot01b      none         swap       sw      0 0
>>>> # swapinfo
>>>> Device          1K-blocks     Used    Avail Capacity
>>>> /dev/label/boot01b  41943040        0 41943040     0%
>>>> # glabel status | grep boot
>>>>    label/boot01     N/A  ada4s1
>>>>    label/boot02     N/A  ada5s1
>>>> # dumpon /dev/label/boot01b
>>>> dumpon: ioctl(DIOCSKERNELDUMP): Operation not supported by device
>>> That's not about label but underlying device that seems to be 
>>> GEOM_PART_MBR
>>> and it allows kernel dumps only if slice (MBR partition) type is 
>>> 0xa5 for "freebsd"
>>> or 0x82 ("linux swap"). Please show output of the command "gpart 
>>> show ada4".
>> Ah, right, please ignore my other reply.  When I actually test it
>> myself, dumpon /dev/label/foo seems to work; I assumed the lack of
>> handling for GEOM::kerneldump in the glabel code was a problem. Sorry
>> for the noise.
>
> I wonder if you are testing the same thing as I am? It looks like you 
> are dumping to a glabel'ed device directly, whereas I am dumping to 
> the b partition of my glabel'ed disk.
>
>

Wait.  Maybe my problem is because I did not setup the b partition 
correctly with fstype swap. I will check it out later.

# bsdlabel /dev/label/boot01
# /dev/label/boot01:
8 partitions:
#          size     offset    fstype   [fsize bsize bps/cpg]
   a:   10485760          1    4.2BSD        0     0     0
   b:   83886080   10485761    4.2BSD        0     0     0
   c:  937703024          0    unused        0     0     # "raw" part, 
don't edit
   d:   41943040   94371841    4.2BSD        0     0     0
   e:   20971520  136314881    4.2BSD        0     0     0
   f:   83886080  157286401    4.2BSD        0     0     0
   g:  696530536  241172481       ZFS