I'm trying to get /var/log to be persistent in my fido build. The default setting on poky is, that there is a symlink in /var which points log -> volatile/log. volatile is a mounted on a tmpfs.
So far i figured out that the symlink should be created by the base-files recipe:
volatiles = "log tmp" do_install () { ... for d in ${volatiles}; do ln -sf volatile/$d ${D}${localstatedir}/$d done ...
I appended the base-files recipe so the link was not created, but it still turned up in my rootfs. So where does it come from? I suspect that maybe the fs-perms.txt has something to do with it. But i tried to create one without the
${localstatedir}/log link volatile/log
line and it still created that link. Any clues?
The base-files recipe creates the basic system directories and makes the volatile symlinks. There is also a second file that affects, it's an initscript that checks volatile directories, symlinks during startup and creates if missing. You should append both base-files and initscripts recipes. Finally, you have to update base-files related links in fs-perms.txt.
I suggest that If there is enough space on your hard drive you could mount /var/log to a different partition from rootfs. That's more practical and safe way if there is something happen on your rootfs partition.
new_log_part is my log partition in this case.
If you create a new partition for logs, you should add it to fstab to automount on startup. Include new fstab in base-files recipe.
The base-files recipe to append:
FILESEXTRAPATHS_prepend := "${THISDIR}/${PN}:" SRC_URI += "file://fstab" dirs755_remove = "${localstatedir}/volatile/log" volatiles_remove = "log" do_install_append () { ln -snf new_log_part ${D}${localstatedir}/log }
initscripts append:
FILESEXTRAPATHS_prepend := "${THISDIR}/${PN}:" SRC_URI += "file://volatiles"
volatiles file:
# This configuration file lists filesystem objects that should get verified # during startup and be created if missing. # # Every line must either be a comment starting with # # or a definition of format: # <type> <owner> <group> <mode> <path> <linksource> # where the items are separated by whitespace ! # # <type> : d|f|l : (d)irectory|(f)ile|(l)ink # # A linking example: # l root root 0777 /var/test /tmp/testfile # f root root 0644 /var/test none # # Understanding links: # When populate-volatile is to verify/create a directory or file, it will first # check it's existence. If a link is found to exist in the place of the target, # the path of the target is replaced with the target the link points to. # Thus, if a link is in the place to be verified, the object will be created # in the place the link points to instead. # This explains the order of "link before object" as in the example above, where # a link will be created at /var/test pointing to /tmp/testfile and due to this # link the file defined as /var/test will actually be created as /tmp/testfile. d root root 0755 /var/volatile/cache none d root root 1777 /var/volatile/lock none d root root 0755 /var/new_log_part none d root root 0755 /var/volatile/run none d root root 1777 /var/volatile/tmp none l root root 0755 /var/cache /var/volatile/cache l root root 1777 /var/lock /var/volatile/lock l root root 0755 /var/log /var/new_log_part l root root 0755 /var/run /var/volatile/run l root root 1777 /var/tmp /var/volatile/tmp d root root 0755 /var/lock/subsys none f root root 0664 /var/new_log_part/wtmp none f root root 0664 /var/run/utmp none l root root 0644 /etc/resolv.conf /var/run/resolv.conf f root root 0644 /var/run/resolv.conf none
fs-perms.txt changes:
# Items from base-files # Links ${localstatedir}/run link volatile/run ${localstatedir}/log link new_log_part ${localstatedir}/lock link volatile/lock ${localstatedir}/tmp link volatile/tmp
Then in the layer's layer.conf file add this line to include new fs-perms.txt:
FILESYSTEM_PERMS_TABLES = "${LAYER_PATH}/fs_files/fs-perms.txt"
Note: You can create your own fs-perm file and append the default one in your conf.layer.
FILESYSTEM_PERMS_TABLES = "fs-perm.txt my-fs-perm.txt"
