Support

Akeeba Backup for Joomla!

#8525 [CLOSED] ZIP archive file is corrupt - SVN186

Posted in ‘Akeeba Backup for Joomla!’
This is a public ticket

Everybody will be able to see its contents. Do not include usernames, passwords or any other sensitive information.

Environment Information

Joomla! version
n/a
PHP version
n/a
Akeeba Backup version
n/a

user12388
A full backup using the zip option with 10mb parts consistently created a corrupt archive file both with post process and without. No errors or warnings were given.

A partial file backup of about 20mb (2 parts) creates a good archive.

Using JPA option creates a valid archive (4x10mb)

David

dlb
Thank you for the report, David. I'll flag this for Nicholas.


Dale L. Brackin
Support Specialist


us.gifEnglish: native


Please keep in mind my timezone and cultural differences when reading my replies. Thank you!


????
My time zone is EST (UTC -5) (click here to see my current time in Philadelphia, PA)

nicholas
Akeeba Staff
Manager
Do you have a log file of that backup process? Also, when saying corrupt archive, which extraction tool did you try to use? Akeeba eXtract Wizard or something else?

Nicholas K. Dionysopoulos

Lead Developer and Director

🇬🇷Greek: native 🇬🇧English: excellent 🇫🇷French: basic • 🕐 My time zone is Europe / Athens
Please keep in mind my timezone and cultural differences when reading my replies. Thank you!

user12388
I had the same problem with a 3.0 pro on the same server with a different domain. The slice sizes were set at 10mb. I changed these to 24mb and the zip files were fine.
I tried opening the corrupt zips with WinRar and with 7-zip.
Unfortunately the logs were set to "errors and warnings"only. There were no messages.

I will try and recreate the problem with full debugging and will get back with the results.

Thanks.
David

nicholas
Akeeba Staff
Manager
7-zip doesn't support standards-compliant split archives. I bought PKZIP, created a split archive and ran it against 7-zip. No luck :) I don't know about WinRAR, I haven't tested that. However, given that all of these utilities - as well as the command line unzip program in Linux and possibly Mac OS X - use the InfoZIP library, I wouldn't expect any of them to work with split archives. The only programs I've found capable of extacting any split archive are PKZIP, WinZIP and our own Akeeba eXtract Wizard and Akeeba Kickstart.

That said, there is a bug in at least the last few dev releases which created invalid central directory records in the end of the ZIP archive. This could cause the archive to appear as corrupt even in compatible tools. If this is the case, please try SVN189 or later from the Developer's Releases section of our site.

Nicholas K. Dionysopoulos

Lead Developer and Director

🇬🇷Greek: native 🇬🇧English: excellent 🇫🇷French: basic • 🕐 My time zone is Europe / Athens
Please keep in mind my timezone and cultural differences when reading my replies. Thank you!

user12388
I have not been able to recreate a bad zip again. Seems like it was a one time event.

You are correct about 7-zip, it cannot open a split archive. WinRar however can and I consider it a reliable tool.

Even before checking the bad zip it was obvious from the file sizes that there was a problem. The total archive was 24mb and it normally split as: .zip = 4317kb, .z01 = 10,240kb and .z02 = 10,240kb. In the case of the bad zip there were 4 files, the first was about 800k, two were 10m and the fourth was about 3.5m.

I will continue to monitor to see if it occurs again.

Thanks,
David

nicholas
Akeeba Staff
Manager
If you're using SVN189 or later, you won't be seeing corrupt ZIP files any more. There was a situation where ZIP files with over 3 parts would get their offsets mixed up in the central directory (the "packing list" attached to the .zip file as per the PKZIP format). The source of this issue was identified and fixed in SVN189.

Nicholas K. Dionysopoulos

Lead Developer and Director

🇬🇷Greek: native 🇬🇧English: excellent 🇫🇷French: basic • 🕐 My time zone is Europe / Athens
Please keep in mind my timezone and cultural differences when reading my replies. Thank you!

Support Information

Working hours: Typically we work Monday to Friday, 9am to 7pm Cyprus timezone (EEST). Support is provided by the same developers writing the software, all of which live in Europe. You can still file tickets, but we cannot respond to them, outside of our working hours.

Support policy: We would like to kindly inform you that when using our support you have already agreed to the Support Policy which is part of our Terms of Service. Thank you for your understanding and for helping us help you!

Summer vacations: Our support will be closed for replies and new tickets from August 6th to August 21st, 2022 due to summer vacations.