oops! I was send to user! I'm very sorry :( >> unionfs-fuse ... yes it is exist in Debian (as backport). >> Why two separate "-o" option group? > one goes to unionfs-fuse and the other to FUSE itself. > >> The branch(?) is "/tmp/var"=RW:"/var"=RO "/var" mean that /tmp/var (which >> is created at /tmp which is a tmpfs - ramdisk) as writable and it is branch over /var which is read only. My interpretation is correct? > Yes, it is. > >>> I haven't figured out a way to do it using AuFS without moving /var, >> What is that mean? Moving /var, basically possible only after mount root file system, which includes it. Suggestion about unionfs (I have got from >> hup.hu) is working if I copy some part of /var to place for rw area for /var. The translation: >> You should make a script which is should run first at the start (rcS.d/S00unionfs), and it should do the next: >> >> - create a ramdisk >> >> mount -nt tmpfs tmpfs /mnt/tmpfs >> >> - copy/create appropriate directories: >> >> tar -xzf /etc/unionfs/var.tar.gz >> >> - and create a union mount: >> >> mount -t unionfs unionfs /var -o dirs=/mnt/tmpfs:/var >> >> Many places I have read that aufs could do the same things. It is not true >> for my situation? >> >> Sincerely >> tovis > > AuFS cannot union mount its own mountpoint, so I don't think it's possible. At least I couldn't get such setups to work. > The only way to make it work is to copy all the files from /var to /var.real and perform the union mount early in the boot process before anything is written to /var, like this: > rm -rf /var > mkdir /var > mount -t aufs aufs "/var" -o dirs="/tmp/var"=rw:"/var.real"=ro > > It could be work! unionfs also needs some files to copy on ramdisk before unify - but note all of them! Also, may I skip the remove /var? - can I use something like /var.real at boot and immediately after mount of / simply mount aufs as you suggest? Question, that do I need /var before mount of root file system?
This idea direct me to one of my first idea, rename /var to /var.real, make a mount of /var as tmpfs, copy whole bunch under /var.real to ram disk. The disadvantages of this solution is obvious. What to do if ram is full, and what to do if I want to keep something from unified /var? Anyway I need to explore boot process in details, and find a point where the script should be put. Does not meter what version I will use. Thanks tovis ------------------------------------------------------------------------------ All the data continuously generated in your IT infrastructure contains a definitive record of customers, application performance, security threats, fraudulent activity, and more. Splunk takes this data and makes sense of it. IT sense. And common sense. http://p.sf.net/sfu/splunk-novd2d
