Unexpected journaling block?

[Namke]

Hello there

I'm perform adding to zpaq archive today, the result was fine, nothing exceptional. However when I perform an test (t command) in this archive, there are numerous of warning saying "skipping block at xxx: unexpected journaling block" popup.

Is this messages harmful and what does it mean, what could cause of this case?

Thanks

[Namke]

Addtional infomation:

• The previous archive version were good, no issue at all.
• Result of the test, zpaq spawn red at "65757! cannot read_archive (9.910) THIS IS VERY BAD!!!" and continue to check the previous archive. I guess recent addtional archive were corrupt?
• However during the compression phase, no error was found.
• Low chance there are issue with disks since this happening in both machine, same set of data.
• Zpaq version v63.1p-JIT,SFTP-L,HW BLK3,SHA1/2,4,SFX64 55.1,(2025-08-13), Windows.

[fcorbelli]

Your archive is heavely corrupted cannot read_archive (9.910) THIS IS VERY BAD means there are almost 10.000 errors

You seems to have unrecognized blocks skipping block at xxx: unexpected journaling bloc

Just an educated guess: you write a corrupted piece of data (disk full?) that fuked the structure somewhere

If the file is not huge you can even try a dump to spot the exact point

zpaqfranz dump zarc.zpaq -out 1.txt -silent

You will get something like that (on the 1.txt file)

...
03037: 00001941 I jDC20190527163017i0000000001 @        2.915.600.997:      8.745 [        15.386] 
...
03037: 00001942 C jDC20190527173017c0000075239 @        2.915.609.743:        103 [             8] d-compr  10.828.818
03037: 00001943 D jDC20190527173017d0000075239 @        2.915.609.847:    803.116 [     1.864.568] 
03037: 00001944 D jDC20190527173017d0000075270 @        2.916.412.964:  6.510.890 [    16.772.174] 
03037: 00001945 D jDC20190527173017d0000075509 @        2.922.923.855:  1.424.922 [     2.646.885] 
03037: 00001946 D jDC20190527173017d0000075539 @        2.924.348.778:  2.089.886 [     7.858.416] 
03037: 00001947 H jDC20190527173017h0000075239 @        2.926.438.665:        845 [           748] d-compr 803.117
03037: 00001948 H jDC20190527173017h0000075270 @        2.926.439.511:      5.838 [         5.740] d-compr 6.510.891
03037: 00001949 H jDC20190527173017h0000075509 @        2.926.445.350:        821 [           724] d-compr 1.424.923
03037: 00001950 H jDC20190527173017h0000075539 @        2.926.446.172:      2.358 [         2.260] d-compr 2.089.887
03037: 00001951 I jDC20190527173017i0000000001 @        2.926.448.531:      4.452 [         4.718] 
...
03037: 00001952 C jDC20190527183017c0000075633 @        2.926.452.984:        103 [             8] d-compr  0
...

You'll find the different versions via the same timestamp
jDC20190527163017!=
jDC20190527173017!=
jDC20190527183017

You should get one C block (ak: jump off to skip over)
Many D blocks (aka: the compressed data)
Many H blocks (aka: the hash for the deduplication)
Some I blocks (aka: the filenames stored)

For huge archive dump does not work (it's normal, just a debug tool, nothing more)

Long story short

Suggestion

• find the last version that work
• trim or crop, cutting everything from this point (discarding corrupted data)

1) test with -until X,... until... errors appears

zpaqfranz t zarc.zpaq -until 1
OK
zpaqfranz t zarc.zpaq -until 2
OK
zpaqfranz t zarc.zpaq -until 3
OK
...
zpaqfranz t zarc.zpaq -until 10
OK
zpaqfranz t zarc.zpaq -until 11
=> errors here => crop to 10 (just an example!)

2) crop to this version (suggestion: use -to, this will create another (hopefully) good archive)

In this example 10

zpaqfranz crop \zarc.zpaq -to z:\fixed.zpaq -until 10 -kill

3) test with -paranoid the fixed archive. This will extract z:\fixed.zpaq to z:\somewhere, then hash checking and deleting OK files (you should get an empty z:\somewhere after the run. If not, the archive is really kaputt)

zpaqfranz t z:\fixed.zpaq -to z:\somewhere -paranoid

4) if the compressed files are smaller than RAM, you can try this too

zpaqfranz w z:\fixed.zpaq -ramdisk -test -checksum -ssd -frugal

Or

just discard the .zpaq archive