Homesync

A simple Bash wrapper script for Unison and Inotifywait, in order to syncronize LDAP user roaming home files with the local machine for offline use; while keeping some files and folders on local storage, according to configuration.

 

Functionality

Consider the directory stucture below. The server server.domain.tld provides two NFS shares that are mounted on login via AutoFS.

• /ldap contains your user's roaming home directory

• /share contains your user's personal directories like Documents, Images, Music, Videos, etc.

• /home/ldap contains your user's local home directory. Here lie all files and directories that are machine-specific (e.g. .bash_history, .cache)

• /storage is the user's primary computer local file storage

Note: Dotted lines represent symbolic links.

 

Homesync works in 2 stages:

Login:

1. The script will start by syncronizing /ldap/bob with the underlying directory that has been mounted over;

2. Home directory /ldap/bob symbolic links will point to either /share/users/bob (if mounted), or the local /storage;

3. An inotifywait watcher will start to monitor create, delete, modify and attrib events on /share to continuously sync files with /storage, throughout the session, with unison.

Logout:

1. Home directory /ldap/bob is synchronized one last time;

2. All homesync processes started by the current user session are killed (SIGTERM)

 

Usage

homesync -arg
    -a  Online: Sync roaming home with local home, and network share with local storage 
        Offline: Change symlinks to local storage 
    -d  Setup local home directory structure
    -h  Show this help message and exit
    -k  Kill all homesync processes started by the current user session
    -l  Setup home directory symlinks according to mount status
    -r  Only sync network share with local storage
    -s  Only sync roaming home with the underlying directory

 

Configuration

Name	Type	Description
DEBUG	Boolean	If events should be logged in LOG_FILE.
LOG_FILE	String	Where DEBUG will log events. By default it's ~/.log/homesync.log.
LDAP_URL	String	Can be configured with an FQDN or IP address (e.g. ldap://domain.tld).
LDAP_DN	String	Your domain's full distinguished name (e.g. dc=domain,dc=tld).
LDAP_BIND	String	Optional user that will bind to the LDAP server (e.g. cn=username,dc=domain,dc=tld). Can be set to false. Since LDAP_BIND_PW is stored in plaintext, it's recommended to create a read-only user.
LDAP_BIND_PW	String	Plaintext LDAP_BIND user password.
LDAP_MACHINE_ATTRIBUTE	String	Any field in your LDAP user entry where you can define its own primary computer hostname for local storage syncronization. By default it's inetOrgPerson homePostalAddress.
BIND_PATH	String	Location where / will be bind mounted on homesync -s (e.g. /mnt/bind). This is used to sync the user's roaming home with the underlying directory which has been mounted over.
UNISON_ARGS	String	Space-separated list of options to use during syncs (e.g. -batch -silent -log=false -owner -group -prefer=newer). For more options, refer to the unison repository.
STORAGE_REMOTE	String	Path of the mounted network share which contains your users' personal files (e.g. /share/users).
STORAGE_LOCAL	String	Path of the local directory which contains the user's personal files (e.g. /storage). This directory is synchronized with STORAGE_REMOTE only if the current machine that is running homesync is the user's primary computer defined in LDAP_MACHINE_ATTRIBUTE.
STORAGE_LOCAL_NAME	String	Name of the symbolic link that will be created in the user's home, and point to either STORAGE_REMOTE or STORAGE_LOCAL, depending on if the user is logged on with a roaming or local directory.
STORAGE_DIRS_SYNC	String	Space-separated list of directories to be synchronized between STORAGE_REMOTE and STORAGE_LOCAL, and symlinked in $HOME (e.g. Documents Images).
STORAGE_DIRS_NOSYNC	String	Optional space-separated list of directories to be kept locally in STORAGE_LOCAL and symlinked in $HOME (e.g. Music Videos). Can be set to false.
HOME_LOCAL	String	Local diretory path which will store users' machine-specific files and folders (e.g. /home/ldap).
HOME_DIRS	String	Space-separated list of directories to be created locally in HOME_LOCAL and symlinked in $HOME with homesync -d (e.g. .cache .local Desktop).
HOME_FILES	String	Space-separated list of files to be created locally in HOME_LOCAL and symlinked in $HOME with homesync -d (e.g. .viminfo file.txt). The user's shell history dotfile is created automatically.

 

Installation

1. Install dependencies:

   sudo apt install inotify-tools ldap-utils unison

2. Download the script and its configuration file to their respective destination:

   sudo wget https://raw.githubusercontent.com/RicardoJeronimo/homesync/master/homesync -O /usr/bin/homesync;
   sudo wget https://raw.githubusercontent.com/RicardoJeronimo/homesync/master/homesync.conf -O /etc/homesync.conf;
   sudo chmod +x /usr/bin/homesync

3. Allow your users to mount BIND_PATH without sudo on /etc/fstab:

   /       /mnt/bind       none        bind,user,noauto        0 0

4. Setup homesync to run at logon (e.g. on .profile):

   homesync -a

5. Setup homesync to run at logoff (e.g. on .bash_logout):

   homesync -d && homesync -k