adding syncdaemon

Signed-off-by: Csaba Henk <csaba@gluster.com>
Signed-off-by: Anand V. Avati <avati@dev.gluster.com>

BUG: 2310 (georeplication)
URL: http://bugs.gluster.com/cgi-bin/bugzilla3/show_bug.cgi?id=2310

13 files changed, 1217 insertions, 1 deletions

diff --git a/configure.ac b/configure.ac
index e8d3c07a8..3ce78028f 100644
--- a/configure.ac
+++ b/configure.ac
@@ -93,6 +93,9 @@ AC_CONFIG_FILES([Makefile
 		xlators/features/quota/src/Makefile
                 xlators/features/marker/Makefile
                 xlators/features/marker/src/Makefile
+                xlators/features/marker/utils/Makefile
+                xlators/features/marker/utils/gsyncd
+                xlators/features/marker/utils/syncdaemon/Makefile
 		xlators/features/read-only/Makefile
 		xlators/features/read-only/src/Makefile
 		xlators/features/mac-compat/Makefile
@@ -281,6 +284,36 @@ AC_SUBST(RDMA_SUBDIR)
 # end IBVERBS section
 
 
+# SYNCDAEMON section
+AC_ARG_ENABLE([georeplication],
+	      AC_HELP_STRING([--disable-georeplication],
+			     [Do not install georeplication components]))
+
+BUILD_SYNCDAEMON=no
+if test "x$enable_georeplication" != "xno"; then
+  SYNCDAEMON_SUBDIR=utils
+  BUILD_SYNCDAEMON="yes"
+  AM_PATH_PYTHON([2.4])
+  echo -n "checking if python is python 2.x... "
+  if echo $PYTHON_VERSION | grep ^2; then
+    :
+  else
+    echo no
+    AC_MSG_ERROR([only python 2.x is supported])
+  fi
+  echo -n "checking if python has ctypes support... "
+  if "$PYTHON" -c 'import ctypes' 2>/dev/null; then
+    echo yes
+  else
+    echo no
+    AC_MSG_ERROR([python does not have ctypes support])
+  fi
+fi
+
+AC_SUBST(SYNCDAEMON_SUBDIR)
+# end SYNCDAEMON section
+
+
 dnl FreeBSD > 5 has execinfo as a Ported library for giving a workaround
 dnl solution to GCC backtrace functionality
 
@@ -430,4 +463,5 @@ echo "epoll IO multiplex : $BUILD_EPOLL"
 echo "argp-standalone    : $BUILD_ARGP_STANDALONE"
 echo "fusermount         : $BUILD_FUSERMOUNT"
 echo "readline           : $BUILD_READLINE"
+echo "georeplication     : $BUILD_SYNCDAEMON"
 echo
diff --git a/xlators/features/marker/Makefile.am b/xlators/features/marker/Makefile.am
index a985f42a8..a6ba2de16 100644
--- a/xlators/features/marker/Makefile.am
+++ b/xlators/features/marker/Makefile.am
@@ -1,3 +1,3 @@
-SUBDIRS = src
+SUBDIRS = src @SYNCDAEMON_SUBDIR@
 
 CLEANFILES =
diff --git a/xlators/features/marker/utils/Makefile.am b/xlators/features/marker/utils/Makefile.am
new file mode 100644
index 000000000..8aefea401
--- /dev/null
+++ b/xlators/features/marker/utils/Makefile.am
@@ -0,0 +1,7 @@
+SUBDIRS = syncdaemon
+
+gsyncddir = $(libexecdir)
+
+gsyncd_SCRIPTS = gsyncd
+
+CLEANFILES =
diff --git a/xlators/features/marker/utils/gsyncd.in b/xlators/features/marker/utils/gsyncd.in
new file mode 100755
index 000000000..9bbf8041f
--- /dev/null
+++ b/xlators/features/marker/utils/gsyncd.in
@@ -0,0 +1,7 @@
+#!/bin/sh
+
+prefix="@prefix@"
+exec_prefix="@exec_prefix@"
+libexecdir=`eval echo "@libexecdir@"`
+
+PYTHONPATH="$libexecdir"/python exec @PYTHON@ -c "from syncdaemon import gsyncd; gsyncd.main()" -c @sysconfdir@/glusterfs/gsyncd.conf "$@"
diff --git a/xlators/features/marker/utils/syncdaemon/Makefile.am b/xlators/features/marker/utils/syncdaemon/Makefile.am
new file mode 100644
index 000000000..1d5014a9e
--- /dev/null
+++ b/xlators/features/marker/utils/syncdaemon/Makefile.am
@@ -0,0 +1,5 @@
+syncdaemondir = $(libexecdir)/python/syncdaemon
+
+syncdaemon_PYTHON = gconf.py gsyncd.py __init__.py master.py README.md repce.py resource.py simplecfg.py
+
+CLEANFILES =
diff --git a/xlators/features/marker/utils/syncdaemon/README.md b/xlators/features/marker/utils/syncdaemon/README.md
new file mode 100644
index 000000000..d45006932
--- /dev/null
+++ b/xlators/features/marker/utils/syncdaemon/README.md
@@ -0,0 +1,81 @@
+gsycnd, the Gluster Syncdaemon
+==============================
+
+REQUIREMENTS
+------------
+
+_gsyncd_ is a program which can operate either in _master_ or in _slave_ mode.
+Requirements are categorized according to this.
+
+* supported OS is GNU/Linux
+* Python >= 2.5, or 2.4 with Ctypes (see below) (both)
+* OpenSSH >= 4.0 (master) / SSH2 compliant sshd (eg. openssh) (slave)
+* rsync (both)
+* glusterfs with marker support (master); glusterfs (optional on slave)
+* FUSE; for supported versions consult glusterfs
+
+INSTALLATION
+------------
+
+As of now, the supported way of operation is running from the source directory.
+
+If you use Python 2.4.x, you need to install the [Ctypes module](http://python.net/crew/theller/ctypes/).
+
+CONFIGURATION
+-------------
+
+gsyncd tunables are a subset of the long command-line options; for listing them,
+type
+
+    gsyncd.py --help
+
+and see the long options up to "--config-file". (The leading double dash should be omitted;
+interim underscores and dashes are interchangeable.) The set of options bear some resemblance
+to those of glusterfs and rsync.
+
+The config file format matches the following syntax:
+
+      <option1>: <value1>
+      <option2>: <value2>
+      # comment
+
+By default (unless specified by the option `-c`), gsyncd looks for config file at _conf/gsyncd.conf_
+in the source tree.
+
+USAGE
+-----
+
+gsyncd is a utilitly for continous mirroring, ie. it mirrors master to slave incrementally.
+Assume we have a gluster volume _pop_ at localhost. We try to set up the following mirrors
+for it with gysncd:
+
+1. _/data/mirror_
+2. local gluster volume _yow_
+3. _/data/far_mirror_ at example.com
+4. gluster volume _moz_ at example.com
+
+The respective gsyncd invocations are (demoing some syntax sugaring):
+
+1.
+
+      gsyncd.py gluster://localhost:pop file:///data/mirror
+
+  or short form
+
+      gsyncd.py :pop /data/mirror
+
+2. `gsyncd :pop :yow`
+3.
+
+       gsyncd.py :pop ssh://example.com:/data/far_mirror
+
+  or short form
+
+       gsyncd.py :pop example.com:/data/far_mirror
+
+4. `gsyncd.py :pop example.com::moz`
+
+gsyncd has to be available on both sides; it's location on the remote side has to be specified
+via the "--remote-gsyncd" option (or "remote-gsyncd" config file parameter). (This option can also be
+used for setting options on the remote side, although the suggested mode of operation is to
+set parameters like log file / pid file in the configuration file.)
diff --git a/xlators/features/marker/utils/syncdaemon/__init__.py b/xlators/features/marker/utils/syncdaemon/__init__.py
new file mode 100644
index 000000000..e69de29bb
--- /dev/null
+++ b/xlators/features/marker/utils/syncdaemon/__init__.py
diff --git a/xlators/features/marker/utils/syncdaemon/gconf.py b/xlators/features/marker/utils/syncdaemon/gconf.py
new file mode 100644
index 000000000..7bedce514
--- /dev/null
+++ b/xlators/features/marker/utils/syncdaemon/gconf.py
@@ -0,0 +1,13 @@
+import os
+
+class GConf(object):
+    ssh_ctl_dir = None
+    ssh_ctl_args = None
+    cpid = None
+
+    @classmethod
+    def setup_ssh_ctl(cls, ctld):
+        cls.ssh_ctl_dir = ctld
+        cls.ssh_ctl_args = ["-oControlMaster=auto", "-S", os.path.join(ctld, "gsycnd-ssh-%r@%h:%p")]
+
+gconf = GConf()
diff --git a/xlators/features/marker/utils/syncdaemon/gsyncd.py b/xlators/features/marker/utils/syncdaemon/gsyncd.py
new file mode 100644
index 000000000..f84df5021
--- /dev/null
+++ b/xlators/features/marker/utils/syncdaemon/gsyncd.py
@@ -0,0 +1,230 @@
+#!/usr/bin/env python
+
+import os
+import os.path
+import sys
+import time
+import logging
+import signal
+import select
+import shutil
+import optparse
+from optparse import OptionParser, SUPPRESS_HELP
+from logging import Logger
+from errno import EEXIST, ENOENT
+
+from gconf import gconf
+import resource
+from simplecfg import SimpleCfg
+
+class GLogger(Logger):
+
+    def makeRecord(self, name, level, *a):
+        rv = Logger.makeRecord(self, name, level, *a)
+        rv.nsecs = (rv.created - int(rv.created)) * 1000000
+        fr = sys._getframe(4)
+        callee = fr.f_locals.get('self')
+        if callee:
+            ctx = str(type(callee)).split("'")[1].split('.')[-1]
+        else:
+            ctx = '<top>'
+        if not hasattr(rv, 'funcName'):
+            rv.funcName = fr.f_code.co_name
+        rv.lvlnam = logging.getLevelName(level)[0]
+        rv.ctx = ctx
+        return rv
+
+    @classmethod
+    def setup(cls, **kw):
+        lprm = {'datefmt': "%Y-%m-%d %H:%M:%S",
+                'format': "[%(asctime)s.%(nsecs)d] %(lvlnam)s [%(module)s:%(lineno)s:%(funcName)s] %(ctx)s: %(message)s"}
+        lprm.update(kw)
+        lvl = kw.get('level', logging.INFO)
+        if isinstance(lvl, str):
+            lvl = logging.getLevelName(lvl)
+            lprm['level'] = lvl
+        logging.root = cls("root", lvl)
+        logging.setLoggerClass(cls)
+        logging.getLogger().handlers = []
+        logging.basicConfig(**lprm)
+
+
+def startup(**kw):
+    def write_pid(fn):
+        fd = None
+        try:
+            fd = os.open(fn, os.O_CREAT|os.O_TRUNC|os.O_WRONLY|os.O_EXCL)
+            os.write(fd, str(os.getpid()) + '\n')
+        finally:
+            if fd:
+                os.close(fd)
+
+    if kw.get('go_daemon') == 'should':
+        x, y = os.pipe()
+        gconf.cpid = os.fork()
+        if gconf.cpid:
+            os.close(x)
+            sys.exit()
+        os.close(y)
+        # wait for parent to terminate
+        # so we can start up with
+        # no messing from the dirty
+        # ol' bustard
+        select.select((x,), (), ())
+        os.close(x)
+        if getattr(gconf, 'pid_file', None):
+            write_pid(gconf.pid_file + '.tmp')
+            os.rename(gconf.pid_file + '.tmp', gconf.pid_file)
+        os.setsid()
+        dn = os.open(os.devnull, os.O_RDWR)
+        for f in (sys.stdin, sys.stdout, sys.stderr):
+            os.dup2(dn, f.fileno())
+    elif getattr(gconf, 'pid_file', None):
+        try:
+            write_pid(gconf.pid_file)
+        except OSError:
+            gconf.pid_file = None
+            ex = sys.exc_info()[1]
+            if ex.errno == EEXIST:
+                sys.stderr.write("pidfile is taken, exiting.\n")
+                exit(2)
+            raise
+
+    lkw = {'level': gconf.log_level}
+    if kw.get('log_file'):
+        lkw['filename'] = kw['log_file']
+    GLogger.setup(**lkw)
+
+def finalize(*a):
+    if getattr(gconf, 'pid_file', None):
+        if gconf.cpid:
+            while True:
+                f = open(gconf.pid_file)
+                pid = f.read()
+                f.close()
+                pid = int(pid.strip())
+                if pid == gconf.cpid:
+                    break
+                if pid != os.getpid():
+                    raise RuntimeError("corrupt pidfile")
+                if os.waitpid(gconf.cpid, os.WNOHANG)[0] == gconf.cpid:
+                    break;
+                time.sleep(0.1)
+        else:
+            try:
+                os.unlink(gconf.pid_file)
+            except:
+                ex = sys.exc_info()[1]
+                if ex.errno == ENOENT:
+                    pass
+                else:
+                    raise
+    if gconf.ssh_ctl_dir and not gconf.cpid:
+        shutil.rmtree(gconf.ssh_ctl_dir)
+
+def main():
+    # ??? "finally" clause does not take effect with SIGTERM...
+    # but this handler neither does
+    # signal.signal(signal.SIGTERM, finalize)
+    GLogger.setup()
+    try:
+        try:
+            main_i()
+        except:
+            exc = sys.exc_info()[0]
+            if exc != SystemExit:
+                logging.exception("FAIL: ")
+                sys.stderr.write("failed with %s.\n" % exc.__name__)
+                exit(1)
+    finally:
+        finalize()
+
+def main_i():
+    rconf = {'go_daemon': 'should'}
+
+    def store_abs(opt, optstr, val, parser):
+        setattr(parser.values, opt.dest, os.path.abspath(val))
+    def store_local(opt, optstr, val, parser):
+        rconf[opt.dest] = val
+    def store_local_curry(val):
+        return lambda o, oo, vx, p: store_local(o, oo, val, p)
+
+    op = OptionParser(usage="%prog [options...] <master> <slave>", version="%prog 0.0.1")
+    op.add_option('--gluster-command',     metavar='CMD',   default='glusterfs')
+    op.add_option('--gluster-log-file',    metavar='LOGF',  default=os.devnull, type=str, action='callback', callback=store_abs)
+    op.add_option('--gluster-log-level',   metavar='LVL')
+    op.add_option('-p', '--pid-file',      metavar='PIDF',  type=str, action='callback', callback=store_abs)
+    op.add_option('-l', '--log-file',      metavar='LOGF',  type=str, action='callback', callback=store_abs)
+    op.add_option('-L', '--log-level',     metavar='LVL')
+    op.add_option('-r', '--remote-gsyncd', metavar='CMD',   default=os.path.abspath(sys.argv[0]))
+    op.add_option('-s', '--ssh-command',   metavar='CMD',   default='ssh')
+    op.add_option('--rsync-command',       metavar='CMD',   default='rsync')
+    op.add_option('--rsync-extra',         metavar='ARGS',  default='-sS', help=SUPPRESS_HELP)
+    op.add_option('--timeout',             metavar='SEC',   type=int, default=30)
+    op.add_option('--sync-jobs',           metavar='N',     type=int, default=3)
+    op.add_option('--turns',               metavar='N',     type=int, default=0, help=SUPPRESS_HELP)
+
+    op.add_option('-c', '--config-file',   metavar='CONF',  type=str, action='callback', callback=store_local)
+    # duh. need to specify dest or value will be mapped to None :S
+    op.add_option('--listen', dest='listen', help=SUPPRESS_HELP,      action='callback', callback=store_local_curry(True))
+    op.add_option('-N', '--no-daemon', dest="go_daemon",    action='callback', callback=store_local_curry('dont'))
+    op.add_option('--debug', dest="go_daemon",              action='callback', callback=lambda *a: (store_local_curry('dont')(*a),
+                                                                                                    a[-1].values.__dict__.get('log_level') or \
+                                                                                                     a[-1].values.__dict__.update(log_level='DEBUG')))
+    # precedence for sources of values: 1) commandline, 2) cfg file, 3) defaults
+    # -- for this to work out we need to tell apart defaults from explicitly set
+    # options... so churn out the defaults here and call the parser with virgin
+    # values container.
+    defaults = op.get_default_values()
+    opts, args = op.parse_args(values=optparse.Values())
+    if not (len(args) == 2 or (len(args) == 1 and rconf.get('listen'))):
+        sys.stderr.write("error: incorrect number of arguments\n\n")
+        sys.stderr.write(op.get_usage() + "\n")
+        sys.exit(1)
+
+    gconf.__dict__.update(defaults.__dict__)
+    # XXX add global config support
+    if not 'config_file' in rconf:
+        rconf['config_file'] = os.path.join(os.path.dirname(sys.argv[0]), "conf/gsyncd.conf")
+    try:
+        cfg = SimpleCfg()
+        cfg.read(rconf['config_file'])
+        gconf.__dict__.update(cfg)
+    except IOError:
+        ex = sys.exc_info()[1]
+        if ex.errno != ENOENT:
+            raise
+    gconf.__dict__.update(opts.__dict__)
+
+    local = resource.parse_url(args[0])
+    remote = None
+    if len(args) > 1:
+        remote = resource.parse_url(args[1])
+
+    if not local.can_connect_to(remote):
+        raise RuntimeError("%s cannot work with %s" % (local.path, remote and remote.path))
+
+    go_daemon = rconf['go_daemon']
+
+    if isinstance(remote, resource.SSH) and go_daemon == 'should':
+        go_daemon = 'postconn'
+        log_file = None
+    else:
+        log_file = gconf.log_file
+    startup(go_daemon=go_daemon, log_file=log_file)
+
+    logging.info("syncing: %s" % " -> ".join([x.url for x in [local, remote] if x]))
+    if remote:
+        go_daemon = remote.connect_remote(go_daemon=go_daemon)
+        if go_daemon:
+            startup(go_daemon=go_daemon, log_file=gconf.log_file)
+            # complete remote connection in child
+            remote.connect_remote(go_daemon='done')
+    local.connect()
+    local.service_loop(*[r for r in [remote] if r])
+
+    logging.info("exiting.")
+
+
+if __name__ == "__main__":
+    main()
diff --git a/xlators/features/marker/utils/syncdaemon/master.py b/xlators/features/marker/utils/syncdaemon/master.py
new file mode 100644
index 000000000..a2f9f718e
--- /dev/null
+++ b/xlators/features/marker/utils/syncdaemon/master.py
@@ -0,0 +1,240 @@
+import os
+import sys
+import time
+import stat
+import signal
+import logging
+import errno
+from errno import ENOENT, ENODATA
+from threading import Thread, currentThread, Condition, Lock
+
+from gconf import gconf
+
+URXTIME = (-1, 0)
+
+class GMaster(object):
+
+    def get_volinfo(self):
+        self.volume_info = self.master.server.volume_info()
+        if self.volume_info['retval']:
+            raise RuntimeError("master is corrupt")
+        return self.volume_info
+
+    @property
+    def uuid(self):
+        if not getattr(self, '_uuid', None):
+            self._uuid = self.volume_info['uuid']
+        return self._uuid
+
+    @property
+    def volmark(self):
+        return self.volume_info['volume_mark']
+
+    def xtime(self, path, *a, **opts):
+        if a:
+            rsc = a[0]
+        else:
+            rsc = self.master
+        if not 'create' in opts:
+            opts['create'] = rsc == self.master
+        xt = rsc.server.xtime(path, self.uuid)
+        if (isinstance(xt, int) or xt < self.volmark) and opts['create']:
+            t = time.time()
+            sec = int(t)
+            nsec = int((t - sec) * 1000000)
+            xt = (sec, nsec)
+            rsc.server.set_xtime(path, self.uuid, xt)
+        if xt == ENODATA:
+            xt = URXTIME
+        return xt
+
+    def __init__(self, master, slave):
+        self.master = master
+        self.slave = slave
+        self.get_volinfo()
+        self.jobtab = {}
+        self.syncer = Syncer(slave)
+        self.total_turns = int(gconf.turns)
+        self.turns = 0
+        self.start = None
+        self.change_seen = None
+        logging.info('master started on ' + self.uuid)
+        while True:
+            self.crawl()
+
+    def add_job(self, path, label, job, *a, **kw):
+        if self.jobtab.get(path) == None:
+            self.jobtab[path] = []
+        self.jobtab[path].append((label, a, lambda : job(*a, **kw)))
+
+    def wait(self, path, mark):
+        jobs = self.jobtab.pop(path, [])
+        succeed = True
+        for j in jobs:
+            ret = j[-1]()
+            if not ret:
+                succeed = False
+        if succeed:
+            self.sendmark(path, mark)
+        return succeed
+
+    def sendmark(self, path, mark):
+        self.slave.server.set_xtime(path, self.uuid, mark)
+
+    def crawl(self, path='.', xtl=None):
+        if path == '.':
+            if self.start:
+                logging.info("crawl took %.6f" % (time.time() - self.start))
+            time.sleep(1)
+            self.start = time.time()
+            logging.info("crawling...")
+            self.get_volinfo()
+            if self.volume_info['uuid'] != self.uuid:
+                raise RuntimeError("master uuid mismatch")
+        logging.debug("entering " + path)
+        if not xtl:
+            xtl = self.xtime(path)
+        xtr0 = self.xtime(path, self.slave)
+        if isinstance(xtr0, int):
+            xtr = URXTIME
+        else:
+            xtr = xtr0
+        if xtr0 == ENOENT:
+            self.slave.server.mkdir(path)
+        else:
+            if xtr > xtl:
+                raise RuntimeError("timestamp corruption for " + path)
+            if xtl == xtr:
+                if path == '.' and self.total_turns and self.change_seen:
+                    self.turns += 1
+                    self.change_seen = False
+                    logging.info("finished turn #%s/%s" % (self.turns, self.total_turns))
+                    if self.turns == self.total_turns:
+                        logging.info("reached turn limit, terminating.")
+                        os.kill(os.getpid(), signal.SIGTERM)
+                return
+        if path == '.':
+            self.change_seen = True
+        dem, des = ( x.server.entries(path) for x in (self.master, self.slave) )
+        dd = set(des) - set(dem)
+        if dd:
+            self.slave.server.purge(path, dd)
+        chld = []
+        for e in dem:
+            e = os.path.join(path, e)
+            xte = self.xtime(e)
+            if isinstance(xte, int):
+                logging.warn("irregular xtime for %s: %s" % (e, errno.errorcode[xte]))
+            elif xte > xtr:
+                chld.append((e, xte))
+        def indulgently(e, fnc, blame=None):
+            if not blame:
+                blame = path
+            try:
+                return fnc(e)
+            except (IOError, OSError):
+                ex = sys.exc_info()[1]
+                if ex.errno == ENOENT:
+                    logging.warn("salvaged ENOENT for" + e)
+                    self.add_job(blame, 'salvage', lambda: False)
+                    return False
+                else:
+                    raise
+        for e, xte in chld:
+            mo = indulgently(e, lambda e: os.lstat(e).st_mode)
+            if mo == False:
+                continue
+            if stat.S_ISLNK(mo):
+                self.slave.server.symlink(os.readlink(e), e)
+                self.sendmark(e, xte)
+            elif stat.S_ISREG(mo):
+                logging.debug("syncing %s ..." % e)
+                pb = self.syncer.add(e)
+                def regjob(e, xte, pb):
+                    if pb.wait():
+                        logging.debug("synced " + e)
+                        self.sendmark(e, xte)
+                        return True
+                    else:
+                        logging.error("failed to sync " + e)
+                self.add_job(path, 'reg', regjob, e, xte, pb)
+            elif stat.S_ISDIR(mo):
+                if indulgently(e, lambda e: (self.add_job(path, 'cwait', self.wait, e, xte),
+                                             self.crawl(e, xte),
+                                             True)[-1], blame=e) == False:
+                    continue
+            else:
+                # ignore fifos, sockets and special files
+                pass
+        if path == '.':
+            self.wait(path, xtl)
+
+class BoxClosedErr(Exception):
+    pass
+
+class PostBox(list):
+
+    def __init__(self, *a):
+        list.__init__(self, *a)
+        self.lever = Condition()
+        self.open = True
+        self.done = False
+
+    def wait(self):
+        self.lever.acquire()
+        if not self.done:
+            self.lever.wait()
+        self.lever.release()
+        return self.result
+
+    def wakeup(self, data):
+        self.result = data
+        self.lever.acquire()
+        self.done = True
+        self.lever.notifyAll()
+        self.lever.release()
+
+    def append(self, e):
+        self.lever.acquire()
+        if not self.open:
+            raise BoxClosedErr
+        list.append(self, e)
+        self.lever.release()
+
+    def close(self):
+        self.lever.acquire()
+        self.open = False
+        self.lever.release()
+
+class Syncer(object):
+
+    def __init__(self, slave):
+        self.slave = slave
+        self.lock = Lock()
+        self.pb = PostBox()
+        for i in range(int(gconf.sync_jobs)):
+            t = Thread(target=self.syncjob)
+            t.setDaemon = True
+            t.start()
+
+    def syncjob(self):
+        while True:
+            pb = None
+            while True:
+                self.lock.acquire()
+                if self.pb:
+                    pb, self.pb = self.pb, PostBox()
+                self.lock.release()
+                if pb:
+                    break
+                time.sleep(0.5)
+            pb.close()
+            pb.wakeup(self.slave.rsync(pb))
+
+    def add(self, e):
+        while True:
+            try:
+                self.pb.append(e)
+                return self.pb
+            except BoxClosedErr:
+                pass
diff --git a/xlators/features/marker/utils/syncdaemon/repce.py b/xlators/features/marker/utils/syncdaemon/repce.py
new file mode 100644
index 000000000..f878d481a
--- /dev/null
+++ b/xlators/features/marker/utils/syncdaemon/repce.py
@@ -0,0 +1,150 @@
+import os
+import sys
+import select
+import time
+import logging
+from threading import Thread, Condition
+try:
+    import thread
+except ImportError:
+    # py 3
+    import _thread as thread
+try:
+    from Queue import Queue
+except ImportError:
+    # py 3
+    from queue import Queue
+try:
+    import cPickle as pickle
+except ImportError:
+    # py 3
+    import pickle
+
+pickle_proto = -1
+
+def ioparse(i, o):
+    if isinstance(i, int):
+        i = os.fdopen(i)
+    # rely on duck typing for recognizing
+    # streams as that works uniformly
+    # in py2 and py3
+    if hasattr(o, 'fileno'):
+        o = o.fileno()
+    return (i, o)
+
+def send(out, *args):
+    os.write(out, pickle.dumps(args, pickle_proto))
+
+def recv(inf):
+    return pickle.load(inf)
+
+
+class RepceServer(object):
+
+    def __init__(self, obj, i, o, wnum=6):
+        self.obj = obj
+        self.inf, self.out = ioparse(i, o)
+        self.wnum = wnum
+        self.q = Queue()
+
+    def service_loop(self):
+        for i in range(self.wnum):
+            t = Thread(target=self.worker)
+            t.setDaemon(True)
+            t.start()
+        try:
+            while True:
+                self.q.put(recv(self.inf))
+        except EOFError:
+                logging.info("terminating on reaching EOF.")
+
+    def worker(self):
+        while True:
+            in_data = self.q.get(True)
+            rid = in_data[0]
+            rmeth = in_data[1]
+            exc = False
+            try:
+                res = getattr(self.obj, rmeth)(*in_data[2:])
+            except:
+                res = sys.exc_info()[1]
+                exc = True
+                logging.exception("call failed: ")
+            send(self.out, rid, exc, res)
+
+
+class RepceJob(object):
+
+    def __init__(self, cbk):
+        self.rid = (os.getpid(), thread.get_ident(), time.time())
+        self.cbk = cbk
+        self.lever = Condition()
+        self.done = False
+
+    def __repr__(self):
+        return ':'.join([str(x) for x in self.rid])
+
+    def wait(self):
+        self.lever.acquire()
+        if not self.done:
+            self.lever.wait()
+        self.lever.release()
+        return self.result
+
+    def wakeup(self, data):
+        self.result = data
+        self.lever.acquire()
+        self.done = True
+        self.lever.notify()
+        self.lever.release()
+
+
+class RepceClient(object):
+
+    def __init__(self, i, o):
+        self.inf, self.out = ioparse(i, o)
+        self.jtab = {}
+        t = Thread(target = self.listen)
+        t.setDaemon(True)
+        t.start()
+
+    def listen(self):
+        while True:
+            select.select((self.inf,), (), ())
+            rid, exc, res = recv(self.inf)
+            rjob = self.jtab.pop(rid)
+            if rjob.cbk:
+                rjob.cbk(rjob, [exc, res])
+
+    def push(self, meth, *args, **kw):
+        cbk = kw.get('cbk')
+        if not cbk:
+            def cbk(rj, res):
+                if res[0]:
+                    raise res[1]
+        rjob = RepceJob(cbk)
+        self.jtab[rjob.rid] = rjob
+        logging.debug("call %s %s%s ..." % (repr(rjob), meth, repr(args)))
+        send(self.out, rjob.rid, meth, *args)
+        return rjob
+
+    def __call__(self, meth, *args):
+        rjob = self.push(meth, *args, **{'cbk': lambda rj, res: rj.wakeup(res)})
+        exc, res = rjob.wait()
+        if exc:
+            logging.error('call %s (%s) failed on peer with %s' % (repr(rjob), meth, str(type(res).__name__)))
+            raise res
+        logging.debug("call %s %s -> %s" % (repr(rjob), meth, repr(res)))
+        return res
+
+    class mprx(object):
+
+        def __init__(self, ins, meth):
+            self.ins = ins
+            self.meth = meth
+
+        def __call__(self, *a):
+            return self.ins(self.meth, *a)
+
+    def __getattr__(self, meth):
+        return self.mprx(self, meth)
diff --git a/xlators/features/marker/utils/syncdaemon/resource.py b/xlators/features/marker/utils/syncdaemon/resource.py
new file mode 100644
index 000000000..bbf7459bb
--- /dev/null
+++ b/xlators/features/marker/utils/syncdaemon/resource.py
@@ -0,0 +1,372 @@
+import re
+import os
+import sys
+import time
+import errno
+import struct
+import select
+import logging
+import tempfile
+import threading
+from ctypes import *
+from ctypes.util import find_library
+from errno import EEXIST, ENOENT, ENODATA, ENOTDIR
+
+from gconf import gconf
+import repce
+from repce import RepceServer, RepceClient
+from master import GMaster
+
+UrlRX  = re.compile('\A(\w+)://(.*)')
+HostRX = re.compile('[a-z\d](?:[a-z\d.-]*[a-z\d])?', re.I)
+UserRX = re.compile("[\w!\#$%&'*+-\/=?^_`{|}~]+")
+
+def sup(x, *a, **kw):
+    return getattr(super(type(x), x), sys._getframe(1).f_code.co_name)(*a, **kw)
+
+def desugar(ustr):
+    m = re.match('([^:]*):(.*)', ustr)
+    if m:
+        if not m.groups()[0]:
+            return "gluster://localhost" + ustr
+        elif '@' in m.groups()[0] or re.search('[:/]', m.groups()[1]):
+            return "ssh://" + ustr
+        else:
+            return "gluster://#{str}"
+    else:
+        return "file://" + os.path.abspath(ustr)
+
+def parse_url(ustr):
+    m = UrlRX.match(ustr)
+    if not m:
+        ustr = desugar(ustr)
+    m = UrlRX.match(ustr)
+    if not m:
+        raise RuntimeError("malformed url")
+    sch, path = m.groups()
+    this = sys.modules[__name__]
+    if not hasattr(this, sch.upper()):
+        raise RuntimeError("unknown url scheme " + sch)
+    return getattr(this, sch.upper())(path)
+
+
+class Xattr(object):
+
+    libc = CDLL(find_library("libc"))
+
+    @classmethod
+    def geterrno(cls):
+        return c_int.in_dll(cls.libc, 'errno').value
+
+    @classmethod
+    def raise_oserr(cls):
+        errn = cls.geterrno()
+        raise OSError(errn, os.strerror(errn))
+
+    @classmethod
+    def lgetxattr(cls, path, attr, siz=0):
+        if siz:
+            buf = create_string_buffer('\0' * siz)
+        else:
+            buf = None
+        ret = cls.libc.lgetxattr(path, attr, buf, siz)
+        if ret == -1:
+            cls.raise_oserr()
+        if siz:
+            return buf.raw[:ret]
+        else:
+            return ret
+
+    @classmethod
+    def lsetxattr(cls, path, attr, val):
+        ret = cls.libc.lsetxattr(path, attr, val, len(val), 0)
+        if ret == -1:
+            cls.raise_oserr()
+
+
+class Server(object):
+
+    GX_NSPACE = "trusted.glusterfs"
+
+    @staticmethod
+    def entries(path):
+        try:
+            return os.listdir(path)
+        except OSError:
+            ex = sys.exc_info()[1]
+            if ex.errno == ENOTDIR:
+                return []
+            else:
+                raise
+
+    @classmethod
+    def purge(cls, path, entries=None):
+        me_also = entries == None
+        if not entries:
+            try:
+                entries = os.listdir(path)
+            except OSError:
+                ex = sys.exc_info()[1]
+                if ex.errno in (ENOTDIR, ENOENT):
+                    try:
+                        os.unlink(path)
+                        return
+                    except OSError:
+                        ex = sys.exc_info()[1]
+                        if ex.errno != ENOENT:
+                            raise
+                else:
+                    raise
+        for e in entries:
+            cls.purge(os.path.join(path, e))
+        if me_also:
+            os.rmdir(path)
+
+    @classmethod
+    def _create(cls, path, ctor):
+        try:
+            ctor(path)
+        except OSError:
+            ex = sys.exc_info()[1]
+            if ex.errno == EEXIST:
+                cls.purge(path)
+                return ctor(path)
+            raise
+
+    @classmethod
+    def mkdir(cls, path):
+        cls._create(path, os.mkdir)
+
+    @classmethod
+    def symlink(cls, lnk, path):
+        cls._create(path, lambda p: os.symlink(lnk, p))
+
+    @classmethod
+    def xtime(cls, path, uuid):
+        try:
+            return struct.unpack('!II', Xattr.lgetxattr(path, '.'.join([cls.GX_NSPACE, uuid, 'xtime']), 8))
+        except OSError:
+            ex = sys.exc_info()[1]
+            if ex.errno in (ENOENT, ENODATA):
+                return ex.errno
+            else:
+                raise
+
+    @classmethod
+    def set_xtime(cls, path, uuid, mark):
+        Xattr.lsetxattr(path, '.'.join([cls.GX_NSPACE, uuid, 'xtime']), struct.pack('!II', *mark))
+
+    @staticmethod
+    def pid():
+        return os.getpid()
+
+    lastping = 0
+    @classmethod
+    def ping(cls):
+        cls.lastping += 1
+        return cls.lastping
+
+
+class SlaveLocal(object):
+
+    def can_connect_to(self, remote):
+        return not remote
+
+    def service_loop(self):
+        repce = RepceServer(self.server, sys.stdin, sys.stdout, int(gconf.sync_jobs))
+        t = threading.Thread(target=repce.service_loop)
+        t.setDaemon(True)
+        t.start()
+        logging.info("slave listening")
+        if gconf.timeout and int(gconf.timeout) > 0:
+            while True:
+                lp = self.server.lastping
+                time.sleep(int(gconf.timeout))
+                if lp == self.server.lastping:
+                    logging.info("connection inactive for %d seconds, stopping" % int(gconf.timeout))
+                    break
+        else:
+            select.select((), (), ())
+
+class SlaveRemote(object):
+
+    def connect_remote(self, rargs=[], **opts):
+        slave = opts.get('slave', self.url)
+        ix, ox = os.pipe()
+        iy, oy = os.pipe()
+        pid = os.fork()
+        if not pid:
+            os.close(ox)
+            os.dup2(ix, sys.stdin.fileno())
+            os.close(iy)
+            os.dup2(oy, sys.stdout.fileno())
+            argv = rargs + gconf.remote_gsyncd.split() + ['-N', '--listen', '--timeout', str(gconf.timeout), slave]
+            os.execvp(argv[0], argv)
+        os.close(ix)
+        os.close(oy)
+        return self.start_fd_client(iy, ox, **opts)
+
+    def start_fd_client(self, i, o, **opts):
+        self.server = RepceClient(i, o)
+        if gconf.timeout and int(gconf.timeout) > 0:
+            def pinger():
+                while True:
+                    self.server.ping()
+                    time.sleep(int(gconf.timeout) * 0.5)
+            t = threading.Thread(target=pinger)
+            t.setDaemon(True)
+            t.start()
+
+    def rsync(self, files, *args):
+        if not files:
+            raise RuntimeError("no files to sync")
+        logging.debug("files: " + ", ".join(files))
+        argv = gconf.rsync_command.split() + gconf.rsync_extra.split() + ['-aR'] + files + list(args)
+        return os.spawnvp(os.P_WAIT, argv[0], argv) == 0
+
+
+class AbstractUrl(object):
+
+    def __init__(self, path, pattern):
+        m = re.search(pattern, path)
+        if not m:
+            raise RuntimeError("malformed path")
+        self.path = path
+        return m.groups()
+
+    def scheme(self):
+        return type(self).__name__.lower()
+
+    @property
+    def url(self):
+        return "://".join((self.scheme(), self.path))
+
+
+  ### Concrete resource classes ###
+
+
+class FILE(AbstractUrl, SlaveLocal, SlaveRemote):
+
+    class FILEServer(Server):
+        pass
+
+    server = FILEServer
+
+    def __init__(self, path):
+        sup(self, path, '^/')
+
+    def connect(self):
+        os.chdir(self.path)
+
+    def rsync(self, files):
+        return sup(self, files, self.path)
+
+
+class GLUSTER(AbstractUrl, SlaveLocal, SlaveRemote):
+
+    class GLUSTERServer(Server):
+
+        @classmethod
+        def volume_info(cls):
+            vm = struct.unpack('!' + 'B'*19 + 'II',
+                               Xattr.lgetxattr('.', '.'.join([cls.GX_NSPACE, 'volume-mark']), 27))
+            m = re.match('(.{8})(.{4})(.{4})(.{4})(.{12})', "".join(['%02x' % x for x in vm[2:18]]))
+            uuid = '-'.join(m.groups())
+            return { 'version': vm[0:2],
+                     'uuid'   : uuid,
+                     'retval' : vm[18],
+                     'volume_mark': vm[-2:] }
+
+    server = GLUSTERServer
+
+    def __init__(self, path):
+        self.host, self.volume = sup(self, path, '^(%s):(.+)' % HostRX.pattern)
+
+    def can_connect_to(self, remote):
+        return True
+
+    def connect(self):
+        d = tempfile.mkdtemp()
+        try:
+            argv = [gconf.gluster_command] + \
+                    (gconf.gluster_log_level and ['-L', gConf.gluster_log_level] or []) + \
+                    ['-l', gconf.gluster_log_file, '-s', self.host,
+                     '--volfile-id', self.volume, '--client-pid=-1', d]
+            if os.spawnvp(os.P_WAIT, argv[0], argv):
+                raise RuntimeError("command failed: " + " ".join(argv))
+            logging.debug('auxiliary glusterfs mount in place')
+            os.chdir(d)
+            argv = ['umount', '-l', d]
+            if os.spawnvp(os.P_WAIT, argv[0], argv):
+                raise RuntimeError("command failed: " + " ".join(argv))
+        finally:
+            try:
+                os.rmdir(d)
+            except:
+                logging.warn('stale mount left behind on ' + d)
+        logging.debug('auxiliary glusterfs mount prepared')
+
+    def connect_remote(self, *a, **kw):
+        sup(self, *a, **kw)
+        self.slavedir = "/proc/%d/cwd" % self.server.pid()
+
+    def service_loop(self, *args):
+        if args:
+            GMaster(self, args[0]).crawl()
+        else:
+            sup(self, *args)
+
+    def rsync(self, files):
+        return sup(self, files, self.slavedir)
+
+
+class SSH(AbstractUrl, SlaveRemote):
+
+    def __init__(self, path):
+        self.remote_addr, inner_url = sup(self, path,
+                                          '^((?:%s@)?%s):(.+)' % tuple([ r.pattern for r in (UserRX, HostRX) ]))
+        self.inner_rsc = parse_url(inner_url)
+
+    def can_connect_to(self, remote):
+        return False
+
+    def start_fd_client(self, *a, **opts):
+        if opts['deferred']:
+            return a
+        sup(self, *a)
+        ityp = type(self.inner_rsc)
+        if ityp == FILE:
+            slavepath = self.inner_rsc.path
+        elif ityp == GLUSTER:
+            slavepath = "/proc/%d/cwd" % self.server.pid()
+        else:
+            raise NotImplementedError
+        self.slaveurl = ':'.join([self.remote_addr, slavepath])
+
+    def connect_remote(self, go_daemon=None):
+        if go_daemon == 'done':
+            return self.start_fd_client(*self.fd_pair)
+        gconf.setup_ssh_ctl(tempfile.mkdtemp())
+        deferred = go_daemon == 'postconn'
+        ret = sup(self, gconf.ssh_command.split() + gconf.ssh_ctl_args + [self.remote_addr], slave=self.inner_rsc.url, deferred=deferred)
+        if deferred:
+            # send a ping to peer so that we can wait for
+            # the answer from which we know connection is
+            # established and we can proceed with daemonization
+            # (doing that too early robs the ssh passwd prompt...)
+            # However, we'd better not start the RepceClient
+            # before daemonization (that's not preserved properly
+            # in daemon), we just do a an ad-hoc linear put/get.
+            i, o = ret
+            inf = os.fdopen(i)
+            repce.send(o, None, 'ping')
+            select.select((inf,), (), ())
+            repce.recv(inf)
+            # hack hack hack: store a global reference to the file
+            # to save it from getting GC'd which implies closing it
+            gconf._in_fd_reference = inf
+            self.fd_pair = (i, o)
+            return 'should'
+
+    def rsync(self, files):
+        return sup(self, files, '-ze', " ".join(gconf.ssh_command.split() + gconf.ssh_ctl_args), self.slaveurl)
diff --git a/xlators/features/marker/utils/syncdaemon/simplecfg.py b/xlators/features/marker/utils/syncdaemon/simplecfg.py
new file mode 100644
index 000000000..fc3863ef4
--- /dev/null
+++ b/xlators/features/marker/utils/syncdaemon/simplecfg.py
@@ -0,0 +1,77 @@
+import re
+import tempfile
+import os
+
+CommentRe = re.compile('\s*(#|$)')
+ParseRe = re.compile('\s*(\S+):\s+(.*\S)\s+$')
+
+class SimpleCfgError(Exception):
+    pass
+
+class SimpleCfg(dict):
+    """
+    Read/write support for a simple config file format.
+    Entries can be of the form "key: value".
+    "#" comments are supported. Whitespace-only lines are ignored.
+    """
+
+    def __init__(self, *a, **kw):
+        dict.__init__(self, *a, **kw)
+        self.klist =  dict.keys(self)
+
+    def __setitem__(self, k, v):
+        k = k.replace('-', '_')
+        if not k in self:
+            self.klist.append(k)
+        dict.__setitem__(self, k, v)
+
+    def __iter__(self):
+        return self.klist.__iter__()
+
+    def keys(self):
+        return self.klist
+
+    def pop(self, key, *a):
+        e = dict.pop(self, key, *a)
+        self.klist.remove(key)
+        return e
+
+    def readstream(self, s):
+        while True:
+            l = s.readline()
+            if not l:
+                break
+            m = ParseRe.match(l)
+            if m:
+                k, v = m.groups()
+                self[k] = v
+            elif not CommentRe.match(l):
+                raise SimpleCfgError('syntax error')
+
+    def writestream(self, s):
+        for k in self:
+            s.write('%s: %s\n' % (k, self[k]))
+
+    def read(self, file):
+        f = None
+        try:
+            f = open(file)
+            self.readstream(f)
+        finally:
+            if f:
+                f.close()
+
+    def write(self, file):
+        tfd = None
+        tfil = None
+        try:
+            tfd, tname = tempfile.mkstemp(dir=os.path.dirname(file))
+            tfil, tfd = os.fdopen(tfd, 'w'), None
+            self.writestream(tfil)
+            os.fsync(tfil.fileno())
+            os.rename(tname, file)
+        finally:
+            if tfd != None:
+                os.close(tfd)
+            if tfil != None:
+                tfil.close()