gzip: *.log.gz: not in gzip format

[wuyinq]

gunzip the zipped log file occurs error like this:

And this is the log init function:

[dveeden]

$ hexdump -C -n2 my.log.gz
00000000  1f 8b                                             |..|
00000002
$ file my.log.gz
my.log.gz: gzip compressed data, original size modulo 2^32 1413

gzip files start with 0x1F, 0x1B (see also "Magic number" on https://en.wikipedia.org/wiki/Gzip). Do your files have the same start bytes?

[wuyinq]

$ hexdump -C -n2 my.log.gz
00000000  1f 8b                                             |..|
00000002
$ file my.log.gz
my.log.gz: gzip compressed data, original size modulo 2^32 1413

gzip files start with 0x1F, 0x1B (see also "Magic number" on https://en.wikipedia.org/wiki/Gzip). Do your files have the same start bytes?

No, brother, I get this:

$ hexdump -C -n2 **.log.gz
00000000   00  00
00000002
$ file **.log.gz
**.log.gz: data 

[tomjschwanke]

Looking at several corrupted files, I can see they contain a lot of zero bytes at the start and some data towards the end. The data does not start with a valid header, so I assume the header would still be at the beginning, but got zeroed somehow

[dveeden]

Is the amount of zeros in the start of the file always the same?

[tomjschwanke]

they are not, tho I'm not sure if it could be related to filesize. However, its interesting that it always follows the same pattern for the files I have:

once data starts, its always the same position in the line

not sure if its coincidence, but a gzip header is 10 bytes long, and its missing exactly 10 bytes from the start of the line