Cannot setup dumpdev on glabel disk

[Samuel Chow]

On 8/31/2018 1:09 PM, 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".
>
>

I do have "freebsd" (0xa5) type configured on the MBR partition.
# gpart show ada4
=>       63  937703025  ada4  MBR  (447G)
          63  937703025     1  freebsd  [active]  (447G)

# gpart show -r ada4
=>       63  937703025  ada4  MBR  (447G)
          63  937703025     1  165  [active]  (447G)