diff --git a/checkzfs.py b/checkzfs.py
new file mode 100644
index 0000000..12d8cd5
--- /dev/null
+++ b/checkzfs.py
@@ -0,0 +1,392 @@
+#!/usr/bin/env python3
+# vim:fenc=utf-8:noet
+##  Copyright 2021 sysops.tv ;-)
+##  BSD-2-Clause
+##
+##  Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:
+## 
+##  1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
+## 
+##  2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
+## 
+## THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
+## THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS
+## BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
+## GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+## LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+VERSION = 1.38
+
+import sys
+import re
+import subprocess
+import time
+import json
+import os.path
+import socket
+from email.message import EmailMessage
+
+class zfscheck(object):
+    ZFSLIST_REGEX = re.compile("^(?P<dataset>.*?)(?:|@(?P<snapshot>.*?))\t(?P<creation>\d+)\t(?P<guid>\d+)\t(?P<used>\d+)\t(?P<referenced>\d+)$",re.M) ## todo used/referenced ... diff zum replica
+    ZFS_LOCAL_SNAPSHOTS = []
+    ZFS_DATASTORES = {}
+    ZFS_RESULT_SNAPSHOT = {}
+    VALIDCOLUMNS = ["dataset","snapshot","creation","guid","used","referenced","size","age","status","copy"] ## valid columns
+    DEFAULT_COLUMNS = ["dataset","snapshot","age","count","copy"] ## default columns
+    DATEFORMAT = "%a %d.%b.%Y %H:%M"
+    COLOR_CONSOLE = {
+        "warn"  : "\033[93m",
+        "crit"  : "\033[91m",
+        "reset" : "\033[0m"
+    }
+    COLUMN_NAMES = {  ## Namen frei editierbar
+        "dataset"   : "Dataset",
+        "snapshot"  : "Snapshotname",
+        "creation"  : "Erstellungszeit",
+        "age"       : "Alter",
+        "count"     : "Anzahl",
+        "used"      : "Größe",
+        "copy"      : "Replikat"
+    }
+    COLUMN_ALIGN = {
+        "dataset"   : "<",
+        "snapshot"  : "<",
+        "copy"      : "<",
+        "status"    : "^"
+    }
+    
+    TIME_MULTIPLICATOR = { ## todo
+        "h" : 60, ## Stunden 
+        "d" : 60*24, ## Tage
+        "w" : 60 * 24 * 7, ## Wochen
+        "m" : 60 * 24 * 30 ## Monat
+    }
+    COLUMN_MAPPER = {}
+    
+    def __init__(self,**kwargs):
+        _start_time = time.time()
+        self.remote = None
+        self.filter = None
+        self.rawdata = False
+        self.sortreverse = False
+        self._check_kwargs(kwargs)
+        _data = self.get_data()
+        _script_runtime = time.time() - _start_time
+        if self.output == "text":
+            print(self.table_output(_data))
+        if self.output == "html":
+            print( self.html_output(_data) )
+        if self.output == "mail":
+            self.mail_output(_data)
+        if self.output == "checkmk":
+            self.checkmk_output(_data)
+        if self.output == "json":
+            print(self.json_output(_data))
+
+        print ("Runtime: {0:.2f}".format(_script_runtime))
+
+    def _check_kwargs(self,kwargs):
+        ## argumente überprüfen
+        for _k,_v in kwargs.items():
+            if _k == "columns":
+                _default = self.DEFAULT_COLUMNS[:]
+
+                if not _v:
+                    self.columns = _default
+                    continue ## defaults
+                # add modus wenn mit + 
+                if not _v.startswith("+"):
+                    _default = []
+                else:
+                    _v = _v[1:]
+                _v = _v.split(",")
+                for _column in _v:
+                    if _column not in self.VALIDCOLUMNS:
+                        raise Exception("invalid column {0} ({1})".format(_v,",".join(self.VALIDCOLUMNS)))
+                    _default.append(_column)
+                _v = list(_default)
+
+
+            if _k == "sort" and _v:
+                ## sortierung desc wenn mit +
+                if _v.startswith("+"):
+                    self.sortreverse = True
+                    _v = _v[1:]
+                if _v not in self.VALIDCOLUMNS:
+                    raise Exception("invalid sort column: {0} ({1})".format(_v,",".join(self.VALIDCOLUMNS)))
+
+            if _k == "threshold" and _v:
+                _v = _v.split(",")
+                ## todo tage etc
+                _v = list(map(int,_v[:2])) ## convert zu int
+                if len(_v) == 1:
+                    _v = (float("inf"),_v[0])
+
+            if _k == "filter" and _v:
+                _v = re.compile(_v)
+
+            setattr(self,_k,_v)
+        
+        ## funktionen zum anzeigen / muss hier da sonst kein self
+        if not self.rawdata:
+            self.COLUMN_MAPPER = {
+                "creation"      : self.convert_ts_date,
+                "age"           : self.seconds2timespan,
+                "used"          : self.format_bytes,
+                "size"          : self.format_bytes,
+                "referenced"    : self.format_bytes,
+            }
+
+    def get_data(self):
+        _data = self._call_proc()
+        self.get_local_snapshots(_data)
+        if self.remote:
+            _data = self._call_proc(self.remote)
+        
+        return self.get_snapshot_results(_data)
+
+    def get_local_snapshots(self,data):
+        for _entry in self._parse(data):
+            _entry.update({
+                "creation"  : int(_entry.get("creation",0))
+            })
+            if _entry.get("snapshot") == None:
+                self.ZFS_DATASTORES[_entry.get("dataset")] = _entry
+            self.ZFS_LOCAL_SNAPSHOTS.append(_entry)
+
+    def get_snapshot_results(self,data):
+        _now = time.time()
+        for _entry in self._parse(data):
+            if _entry.get("snapshot") == None:
+                continue ## TODO 
+            if self.filter and not self.filter.search("{dataset}@{snapshot}".format(**_entry)):
+                continue
+            _timestamp = int(_entry.get("creation",0))
+            _dataset = _entry["dataset"]
+            _entry.update({
+                "creation"  : _timestamp,
+                "age"       : int(_now - _timestamp),
+                "count"     : 1,
+                "size"      : self.ZFS_DATASTORES.get(_dataset,{}).get("used",0),
+                "used"      : int(_entry.get("used",0)),
+                "referenced": int(_entry.get("referenced",0)),
+                "copy"      : "",
+                "status"    : self.check_threshold(_now -_timestamp)
+            })
+            _copys = list(
+                filter(lambda x: x.get("guid") == _entry.get("guid") and x.get("dataset") != _entry.get("dataset") , self.ZFS_LOCAL_SNAPSHOTS)
+            )
+            if len(_copys) > 0:
+                _entry["copy"] = ",".join(["{0}".format(_x.get("dataset")) for _x in _copys])
+            else:
+                if self.backup:
+                    continue
+            _exist_entry = self.ZFS_RESULT_SNAPSHOT.get(_dataset)
+            if _exist_entry:
+                _entry["count"] += _exist_entry.get("count") ## update counter
+                if _exist_entry.get("creation") <= _entry.get("creation"): ## newer
+                    _exist_entry.update(_entry)
+                else:
+                    _exist_entry["count"] = _entry["count"]
+            else:
+                self.ZFS_RESULT_SNAPSHOT[_dataset] = _entry
+                    
+        
+        return list(self.ZFS_RESULT_SNAPSHOT.values())
+
+    def _parse(self,data):
+        _ret = [] ## Fixme
+        for _match in self.ZFSLIST_REGEX.finditer(data):
+            #yield _match.groupdict()
+            _ret.append(_match.groupdict())
+        return _ret
+
+    def _call_proc(self,remote=None):
+        zfs_args = ["zfs", "list", 
+                "-t", "all",  ## list snapshots / TODO:all
+                "-Hp",  ## script und numeric output
+                "-o", "name,creation,guid,used,referenced",  ## attributes to show
+                "-r" ## recursive
+        ]
+        if remote:
+            _privkeyoption = []
+            if self.ssh_identity:
+                _privkeyoption = ["-i",self.ssh_identity]
+            _sshoptions = "BatchMode yes"
+            _parts = remote.split(":")
+            _port = "22"  ## default port
+            if len(_parts) > 1:
+                remote = _parts[0]
+                _port = _parts[1]
+            zfs_args = ["ssh",
+                remote, ## Hostname
+                "-p", _port,
+                "-o", _sshoptions, ## ssh options
+            ] + _privkeyoption + zfs_args
+        _proc = subprocess.Popen(zfs_args,stdout=subprocess.PIPE,stderr=subprocess.PIPE,shell=False)
+        _stdout, _stderr = _proc.communicate()
+        if _proc.returncode > 0:
+            raise Exception(_stderr.decode(sys.stdout.encoding)) ## Raise Errorlevel with Error from proc
+        return _stdout.decode(sys.stdout.encoding)
+
+    def convert_ts_date(self,ts):
+        return time.strftime(self.DATEFORMAT,time.localtime(ts))
+
+    def check_threshold(self,age):
+        if not self.threshold:
+            return "ok"
+        age /= 60 ## default in minuten
+        #print("Age: {0} - {1} - {2}".format(age,list(zip(self.threshold,("warn","crit"))),list(filter(lambda y: y[0] < age,zip(self.threshold,("warn","crit"))))))
+        _status = list(
+            map(lambda x: x[1], ## return only last
+                filter(lambda y: y[0] < age, ## check threshold Texte
+                    zip(self.threshold,("warn","crit"))
+                )
+            )
+        )
+        if not _status:
+            _status = ["ok"]
+        return _status[-1]
+        
+
+    @staticmethod
+    def format_bytes(size,unit='B'):
+        # 2**10 = 1024
+        size = float(size)
+        if size == 0:
+            return "0"
+        power = 2**10
+        n = 0
+        power_labels = {0 : '', 1: 'K', 2: 'M', 3: 'G', 4: 'T'}
+        while size > power:
+            size /= power
+            n += 1
+        return "{0:.2f} {1}{2}".format(size, power_labels[n],unit)
+
+    @staticmethod
+    def seconds2timespan(seconds,details=2,seperator=" ",template="{0:.0f}{1}",fixedview=False):
+        _periods = (
+            ('W', 604800),
+            ('T', 86400),
+            ('Std', 3600),
+            ('Min', 60),
+            ('Sek', 1)
+        )
+        _ret = []
+        for _name, _period in _periods:
+            _val = seconds//_period
+            if _val:
+                seconds -= _val * _period
+                #if _val == 1:
+                #    _name = _name[:-1]
+                _ret.append(template.format(_val,_name))
+            else:
+                if fixedview:
+                    _ret.append("")
+        return seperator.join(_ret[:details])
+
+    def _datasort(self,data):
+        if not self.sort:
+            return data
+        return sorted(data, key=lambda k: k[self.sort],reverse=self.sortreverse)
+
+    def checkmk_output(self,data):
+        if not data:
+            return
+        print ("<<<checkzfs>>>")
+        for _item in data:
+            print("<<{0}>>".format(_item.get("dataset","").replace(" ","_")))
+            for _info,_val in _item.items():
+                print("{0}: {1}".format(_info,_val))
+
+    def table_output(self,data):
+        if not data:
+            return
+        _header = data[0].keys() if not self.columns else self.columns
+        _header_names = [self.COLUMN_NAMES.get(i,i) for i in _header]
+        _converter = dict((i,self.COLUMN_MAPPER.get(i,(lambda x: str(x)))) for i in _header)
+        
+        _output_data = [_header_names]
+        _line_status = []
+        for _item in self._datasort(data):
+            _line_status.append(_item.get("status"))
+            _output_data.append([_converter.get(_col)(_item.get(_col,"")) for _col in _header])
+
+        _maxwidth = [max(map(len,_col)) for _col in zip(*_output_data)] ## max column breite
+        _format = " ║ ".join(["{{:{}{}}}".format(self.COLUMN_ALIGN.get(_h,">"),_w) for _h,_w in zip(_header,_maxwidth)])  ## format bilden
+        _line_print = False
+        _out = []
+        _status = "ok"
+        for _item in _output_data:
+            if _line_print:
+                _status = _line_status.pop(0)
+            if _status != "ok":
+                _out.append(self.COLOR_CONSOLE.get(_status,"") + _format.format(*_item) + self.COLOR_CONSOLE.get("reset"))
+            else:
+                _out.append(_format.format(*_item))
+            if not _line_print:
+                _out.append("═╬═".join(map(lambda x: x*"═",_maxwidth))) ## trennlinie
+                _line_print = True  
+        return "\n".join(_out)
+
+    def html_output(self,data):
+        if not data:
+            return
+        _header = data[0].keys() if not self.columns else self.columns
+        _header_names = [self.COLUMN_NAMES.get(i,i) for i in _header]
+        _converter = dict((i,self.COLUMN_MAPPER.get(i,(lambda x: str(x)))) for i in _header)
+        
+        _out = []
+        _out.append("<html><head>")
+        _out.append("<style type='text/css'>.warn { background-color: yellow } .crit { background-color: red}</style>")
+        _out.append("<title>ZFS</title></head>")
+        _out.append("<body><table border=1>")
+        _out.append("<tr><th>{0}</th></tr>".format("</th><th>".join(_header_names)))
+        for _item in self._datasort(data):
+            _out.append("<tr class='{1}'><td>{0}</td></tr>".format("</td><td>".join([_converter.get(_col)(_item.get(_col,"")) for _col in _header]),_item.get("status","ok")))
+        _out.append("</table></body></html>")
+        return "".join(_out)
+
+    def mail_output(self,data):
+        _msg = EmailMessage()
+        self.hostname = socket.getfqdn()
+        _msg.set_content(self.checkmk_output)
+        _msg.add_alternative(self.html_output(data),subtype="html")
+        _msg["From"] = "ZFS-Checkscript on {0} <root@{0}".format(self.hostname)
+        _msg["To"] = "root@{0}".format(self.hostname)
+        _msg["Content-Type"] 
+        _msg["Subject"] = "ZFS-Check {0}".format(self.hostname.split(".")[0])
+        subprocess.run(["/usr/sbin/sendmail","-t","-oi"], input=_msg.as_bytes())
+
+    def json_output(self,data):
+        return json.dumps(data)
+
+if __name__ == "__main__":
+    import argparse
+
+    _parser = argparse.ArgumentParser("Tool to check ZFS Replication age\n##########################################\n")
+    _parser.add_argument('--remote',type=str,
+                help="SSH Connection Data user@host")
+    _parser.add_argument("--filter",type=str,
+                help="Regex Filter only Snapshots")
+    _parser.add_argument("--pool",type=str,
+                help="Regex Filter only Pool")
+    _parser.add_argument("--output",type=str,default="text",choices=["html","text","mail","checkmk","json"],
+                help="Ausgabeformat")
+    _parser.add_argument("--columns",type=str,
+                help="Show only Columns")
+    _parser.add_argument("--sort",type=str,choices=zfscheck.VALIDCOLUMNS,
+                help="Sort by Column")
+    _parser.add_argument("--threshold",type=str,
+                help="Add Warn/Crit times in minutes")
+    _parser.add_argument("--backup",action="store_true",
+                help="search backups only")
+    _parser.add_argument("--rawdata",action="store_true",
+               help="show times/bytes unconverted")
+    _parser.add_argument("--ssh-identity",type=str,
+                help="Path to ssh private key to use")
+    _parser.add_argument("--ssh-extra-option",type=str,
+                help="additional ssh -o ... options")
+    args = _parser.parse_args()
+    zfscheck(**args.__dict__)
+