Spontaneous byte change in .gz file
The Visitors run I do over all my web log files automatically started complaining about one of the compressed files today:
gzip: /var/www/www.asjo.org/logs/access_log.103.gz: invalid compressed data--crc error gzip: /var/www/www.asjo.org/logs/access_log.103.gz: invalid compressed data--length error
Logging into the machine and testing the file confirms the problem:
$ gzip -t access_log.103.gz gzip: access_log.103.gz: invalid compressed data--crc error gzip: access_log.103.gz: invalid compressed data--length error
So I get a copy of the file from backup; it is the same size, and it isn't invalid according to gzip -t. Let us compare them:
$ cmp --print-bytes access_log.103.gz access_log.103.gz_from_backup access_log.103.gz access_log.103.gz_from_backup differ: byte 189783, line 646 is 40 41 !
One byte changed! Yikes.
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