Run script before loggin starts

Question

Hi everyone
I'm using a tmpfs for my /var/log folder, and because I don't want to loose all logs I have modified /etc/rc.local.shutdown following this thread so everything gets backed up each time in a different folder named after the time at which I shutdown.
https://bbs.archlinux.org/viewtopic.php … 10#p528010
But I'd prefer to have a XYZ folder with all logs which gets loaded to my tmpfs /var/log, so everything works like normal, and finally before shutdown, everything is copied back to folder XYZ. This way my HDD is only accessed for loggin matters at startup and shutdown. So far it's not difficult, except I want to run my script which does just that, before any loggin starts.
How can I execute commands or run a script while booting just between my tmpfs is mounted (declraed in /etc/inittab) and loggin starts? If possible including the minilogger at arch boot
Thanks very much in advance
Last edited by agon (2011-02-24 22:07:02)

Answer 1

Here we are again
I'm trying it now the way you suggest. I've written two simple scripts (my first ones ) which do as following:
[ LOGs => RAM ]
I call to this script in /etc/rc.local. It saves all logs in ram and then links the so that they appear again in /var/log
note: my /tmp folder is a tmpfs
#!/bin/bash
#/usr/bin/log-ram.sh
# Create /tmp/log: necessary for each boot because /tmp is volatile
# Copy /var/log to tmp/log: copy my complete logs to ram
# Rename /var/log to /var/log.backup: so I have a backup of them
# Create a new empty /var/log
#Link /var/log to /tmp/log: all logs (located in ram) appear in /var/log
echo "Copiando LOGs de HDD a RAM"
mkdir /tmp/log
cp -Rp /var/log/* /tmp/log/
mv /var/log /var/log.backup
mkdir /var/log
ln -sf /tmp/log/* /var/log/
Questions:
-Do you recommend calling this script latter or is it here ok (/etc/rc.local)? If it would be latter, where do you reccomend it? As you already noted, it has to be excecuted as root
[ LOGs => HDD ]home sweet home)
I call this script in /etc/rc.local.shutdown
All logs get copied back to /var/log and also a backup is made. Note that each time this script is ececuted a new backup is generated. That menas that for now I have to manually erase them when they get to many. Later (when I learn a bit more of scripting) I'll make the oldest get automatically erased.
#!/bin/bash
#/usr/bin/log-unram.sh
#Refresh the content of /var/backup so it's up to date
#Remove /var/log: so all symbolic links get erased
#Recreate /var/log: is there a faster way to do this and the last step?
#Copy from /tmp to /var: from RAM to HDD
#Rename and change directory of /var/log.backup with an unique identifier (time at which script is run).
echo "Copiando LOGs de RAM a HDD"
now=`date +"%Y%m%d_%Hh%M"`
cp -Rp /tmp/log/* /var/log.backup/
rm -r /var/log
mkdir /var/log
mv /tmp/log /var/log
mv /var/log.backup /var/log.old/$now/
Questions:
Is there a faster way to erase al symbolic links
As said, this are my two first attempts to writte a bash script (excetp the hello world one lol). So I probably did a lot wrong.
For now it seems to work (when calling them from shell) but I still didnt tried them with real powerup & shutdown. (Ill do it after posting this).
Thanks in advance
EDIT:
These scripts are give me problems. I'm trying to make now a syngle script which copies from HDD -> RAM or RAM -> HDD depending on if logs are already loaded or  not. This way If my system crashes I dont have problems while booting (like the firefox-sync script).
As soon as I have something, I'll post it here
Last edited by agon (2011-02-27 13:06:11)