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Removing ‘System Volume Information’ from a NTFS Volume

There’s a quick and easy way to remove the ‘System Volume Information’ folder from a NTFS disk. Run these commands in an elevated shell:

D: (or whichever volume letter you are using)
takeown /r /f "System Volume Information"
rd /s /q "System Volume Information"
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Streaming MySQL backup

This week I needed to backup a Percona MySQL server.
One solution for this, is to stop the MySQL server, create a mysqldump, and transfer it to your backup location.

However, depending on your tables and data size, this might not be the best solution. Especially if the database you want to backup is a live database with active users.

The solution for me was to use xtrabackup (innobackupex) from Percona to stream the database in tar format over SSH to another server:

innobackupex --stream=tar . | ssh user@x.x.x.x "cat - > /mnt/backup/backup.tar"

Once this is done, the other server needs to unpack the tar and prepare the backup:

xtrabackup --prepare --target-dir=/var/lib/mysql

At the end of this command, you should see an OK message.
If all went well, you can now do:

chown -R mysql:mysql /var/lib/mysql

and restart the MySQL server. The binlog position will be included in the output of the xtrabackup --prepare so you can easily set up master/slave syncing.

Finally, I created a cronjob on the MySQL Slave server which will take a daily backup with xtrabackup and upload to a 3rd party secure storage.

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image-orientation CSS property

The other day I was investigating an issue with Chrome 83 and a MJPEG stream embedded in an <img />

The MJPEG stream was streaming an iPhone screen to the end user. When the user decided to rotate the screen (switching between portrait and landscape), the MJPEG stream was updated accordingly when viewing the stream inside a separate tab, but it was not showing correctly when embedded in a HTML image tag.

Turns out that since Chrome 81, the browser will look at the EXIF data to decide the correct orientation. The issue I was experiencing was happening because the EXIF data did not update after each rotation.

The solution was to use image-orientation and apply this CSS rule to the image tag. Once that was in place, the MJPEG stream was showing correctly after each rotation.

More information is available in this Chromium ticket.