HAMMER filesystem check / CRC verification

[PeerCorps Trust Fund]

So after a recent run of hammer show, I get the following:

HAMMER zone statistics
	zone #  blocks       items              used[B]             used[%]
	zone 0  0            0                  0                   0
	zone 1  0            0                  0                   0
	zone 2  0            0                  0                   0
	zone 3  0            0                  0                   0
	zone 4  0            0                  0                   0
	zone 5  0            0                  0                   0
	zone 6  0            0                  0                   0
	zone 7  0            0                  0                   0
	zone 8  201          383556             1571045376          93.1757
	zone 9  2            50127              4809376             28.6661
	zone 10 122556       16105131           1027866722304       99.9798
	zone 11 1            24                 119312              1.42231
	zone 12 0            0                  0                   0
	zone 13 0            0                  0                   0
	zone 14 0            0                  0                   0
	zone 15 0            0                  0                   0
	----------------------------------------------------------------------
	total   122760       16538838           1029442696368       99.9667
54 bad nodes
1895 bad elms

Does this output mean that I should be restoring the above disk from backup or something else is going on here?

Mike


On 01/22/2016 05:57 PM, Tomohiro Kusumi wrote:
> If you are to redirect the hammer show output to a file, it's better to
> write to a file on different filesystem (e.g. ufs or another hammer).
> 
> It's possible that hammer show never ends because what hammer show does is
> run through all ondisk btree nodes. Writing a file is adding nodes into the
> btree of that filesystem.
> 
> 
> 2016-01-23 0:44 GMT+09:00 Tomohiro Kusumi <kusumi.tomohiro at gmail.com>:
> 
>> (resending as i forgot to send to users at ...)
>>
>> # hammer -v -f ${DEV} blockmap
>> # hammer -v -f ${DEV} checkmap
>> # hammer -v -f ${DEV} show
>>
>> These three do some validation from different point of view.
>> If the last two lines of each output says 0 error, then no error was found
>> at least by what these 3 commands test for.
>>
>> Note that there seems to be a bug in hammer where a valid filesystem would
>> still show ^B in hammer show output. I usually run some test scripts (that
>> contain there 3 commands) before I commit something, but I see ^B in hammer
>> show every once in a while. It could be that the way hammer show tests the
>> filesystem is missing something and results in showing errors that aren't
>> really errors. This occurred at least back in DragonFly 4.0 era in 2014,
>> and it still does on 4.4. It has been on my todo list for a long time.
>>
>>
>> 2016-01-22 23:59 GMT+09:00 PeerCorps Trust Fund <ipc at peercorpstrust.org>:
>>
>>> Hi All,
>>>
>>> In ZFS, the command "zpool status" gives a succinct overview of the
>>> status of mounted file systems. In particular, whether there might be
>>> checksum errors on files or other data structures.
>>>
>>>         NAME        STATE     READ WRITE CKSUM
>>>         tank        ONLINE       0     0     0
>>>           ada0p2    ONLINE       0     0     0
>>>
>>> In HAMMER the "show" command provides an extremely detailed output of all
>>> data structures and CRC verifications.
>>>
>>> I've used the command:
>>>
>>> hammer -f /dev/serno/disk-serial-number show |grep B------
>>>
>>> On a mounted disk and the output was clean (nothing) after running for
>>> some time with noted disk activity. Does this mean that all CRCs are valid?
>>> Are there other commands in addition to "show" that allow for validation
>>> and examination of data structures on HAMMER volumes?
>>>
>>> --
>>> Mike
>>>