Request exceeded the limit of 10 internal redirects due to probable configuration error.

I upgraded to Apache 2.4.10 and I am getting these errors for sites which used to work:

AH00124: Request exceeded the limit of 10 internal redirects due to probable configuration error. Use 'LimitInternalRecursion' to increase the limit if necessary. Use 'LogLevel debug' to get a backtrace.

One strange thing is these happen only with .htaccess files. So if I use exactly the same configuration but written in vhosts config file such as /etc/apache2/sites-enabled/000-default.conf all works well. So yes, one quick fix is to put it there. But after doing some tests, I found out apache 2.4 does not like when you redirect stuff to index.php but you don't have a rule for index.php itsels. So simply keeping all rules and adding something like RewriteRule ^index\.php$ - [L] fixed the problem.

[UPDATE] On many other cases it seems to work without any trouble or extra rule, but on that particular one not... strange.

kernel: do_IRQ: No irq handler for vector (irq -1)

On a fresh Debian Jessie I kept getting every couple of minutes this error:
do_IRQ: No irq handler for vector (irq -1)
A suggested solution is to add "pci=nomsi,noaer" in /etc/default/grub at GRUB_CMDLINE_LINUX
However,  noaer refers to PCIE Advanced Error Reporting and I don't want only to hide the mess, I want to fix it (if possible).
Only adding pci=nomsi seems to do the trick so far.
Also don't forget to do a update-grub after you edit /etc/default/grub.

Debian 8 does not execute /etc/rc.local

I have just installed a fresh Debian 8 Jessie and then I put something in /etc/rc.local.
To my suprise, after the reboot, the command did not execute.
Log investigation showed:

Failed to start /etc/rc.local Compatibility.
Failed at step EXEC spawning /etc/rc.local: Exec format error

So I simply added "#!/bin/sh -e" in the first line of rc.local and then it worked well.

Youtube mp3 extract in Debian Linux

youtube-dl --extract-audio --audio-format mp3 [URL]