New upstream version 1.11.0+dfsgupstream/1.11.0+dfsg

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

3 files changed, 886 insertions, 0 deletions

diff --git a/collectors/node.d.plugin/snmp/Makefile.inc b/collectors/node.d.plugin/snmp/Makefile.inc
new file mode 100644
index 000000000..26448a1ce
--- /dev/null
+++ b/collectors/node.d.plugin/snmp/Makefile.inc
@@ -0,0 +1,13 @@
+# SPDX-License-Identifier: GPL-3.0-or-later
+
+# THIS IS NOT A COMPLETE Makefile
+# IT IS INCLUDED BY ITS PARENT'S Makefile.am
+# IT IS REQUIRED TO REFERENCE ALL FILES RELATIVE TO THE PARENT
+
+# install these files
+dist_node_DATA       += snmp/snmp.node.js
+# dist_nodeconfig_DATA += snmp/snmp.conf
+
+# do not install these files, but include them in the distribution
+dist_noinst_DATA       += snmp/README.md snmp/Makefile.inc
+
diff --git a/collectors/node.d.plugin/snmp/README.md b/collectors/node.d.plugin/snmp/README.md
new file mode 100644
index 000000000..a307a3642
--- /dev/null
+++ b/collectors/node.d.plugin/snmp/README.md
@@ -0,0 +1,357 @@
+# SNMP Data Collector
+
+Using this collector, netdata can collect data from any SNMP device.
+
+This collector supports:
+
+- any number of SNMP devices
+- each SNMP device can be used to collect data for any number of charts
+- each chart may have any number of dimensions
+- each SNMP device may have a different update frequency
+- each SNMP device will accept one or more batches to report values (you can set `max_request_size` per SNMP server, to control the size of batches).
+
+## Configuration
+
+You will need to create the file `/etc/netdata/node.d/snmp.conf` with data like the following.
+
+In this example:
+
+ - the SNMP device is `10.11.12.8`.
+ - the SNMP community is `public`.
+ - we will update the values every 10 seconds (`update_every: 10` under the server `10.11.12.8`).
+ - we define 2 charts `snmp_switch.bandwidth_port1` and `snmp_switch.bandwidth_port2`, each having 2 dimensions: `in` and `out`.
+
+```json
+{
+    "enable_autodetect": false,
+    "update_every": 5,
+    "max_request_size": 100,
+    "servers": [
+        {
+            "hostname": "10.11.12.8",
+            "community": "public",
+            "update_every": 10,
+            "max_request_size": 50,
+            "options": { "timeout": 10000 },
+            "charts": {
+                "snmp_switch.bandwidth_port1": {
+                    "title": "Switch Bandwidth for port 1",
+                    "units": "kilobits/s",
+                    "type": "area",
+                    "priority": 1,
+                    "family": "ports",
+                    "dimensions": {
+                        "in": {
+                            "oid": "1.3.6.1.2.1.2.2.1.10.1",
+                            "algorithm": "incremental",
+                            "multiplier": 8,
+                            "divisor": 1024,
+                            "offset": 0
+                        },
+                        "out": {
+                            "oid": "1.3.6.1.2.1.2.2.1.16.1",
+                            "algorithm": "incremental",
+                            "multiplier": -8,
+                            "divisor": 1024,
+                            "offset": 0
+                        }
+                    }
+                },
+                "snmp_switch.bandwidth_port2": {
+                    "title": "Switch Bandwidth for port 2",
+                    "units": "kilobits/s",
+                    "type": "area",
+                    "priority": 1,
+                    "family": "ports",
+                    "dimensions": {
+                        "in": {
+                            "oid": "1.3.6.1.2.1.2.2.1.10.2",
+                            "algorithm": "incremental",
+                            "multiplier": 8,
+                            "divisor": 1024,
+                            "offset": 0
+                        },
+                        "out": {
+                            "oid": "1.3.6.1.2.1.2.2.1.16.2",
+                            "algorithm": "incremental",
+                            "multiplier": -8,
+                            "divisor": 1024,
+                            "offset": 0
+                        }
+                    }
+                }
+            }
+        }
+    ]
+}
+```
+
+`update_every` is the update frequency for each server, in seconds.
+
+`max_request_size` limits the maximum number of OIDs that will be requested in a single call. The default is 50. Lower this number of you get `TooBig` errors in netdata error.log.
+
+`family` sets the name of the submenu of the dashboard each chart will appear under.
+
+If you need to define many charts using incremental OIDs, you can use something like this:
+
+This is like the previous, but the option `multiply_range` given, will multiply the current chart from `1` to `24` inclusive, producing 24 charts in total for the 24 ports of the switch `10.11.12.8`.
+
+Each of the 24 new charts will have its id (1-24) appended at:
+
+1. its chart unique id, i.e. `snmp_switch.bandwidth_port1` to `snmp_switch.bandwidth_port24`
+2. its `title`, i.e. `Switch Bandwidth for port 1` to `Switch Bandwidth for port 24`
+3. its `oid` (for all dimensions), i.e. dimension `in` will be `1.3.6.1.2.1.2.2.1.10.1` to `1.3.6.1.2.1.2.2.1.10.24`
+3. its priority (which will be incremented for each chart so that the charts will appear on the dashboard in this order)
+
+```json
+{
+    "enable_autodetect": false,
+    "update_every": 10,
+    "servers": [
+        {
+            "hostname": "10.11.12.8",
+            "community": "public",
+            "update_every": 10,
+            "options": { "timeout": 20000 },
+            "charts": {
+                "snmp_switch.bandwidth_port": {
+                    "title": "Switch Bandwidth for port ",
+                    "units": "kilobits/s",
+                    "type": "area",
+                    "priority": 1,
+                    "family": "ports",
+                    "multiply_range": [ 1, 24 ],
+                    "dimensions": {
+                        "in": {
+                            "oid": "1.3.6.1.2.1.2.2.1.10.",
+                            "algorithm": "incremental",
+                            "multiplier": 8,
+                            "divisor": 1024,
+                            "offset": 0
+                        },
+                        "out": {
+                            "oid": "1.3.6.1.2.1.2.2.1.16.",
+                            "algorithm": "incremental",
+                            "multiplier": -8,
+                            "divisor": 1024,
+                            "offset": 0
+                        }
+                    }
+                }
+            }
+        }
+    ]
+}
+```
+
+The `options` given for each server, are:
+
+ - `timeout`, the time to wait for the SNMP device to respond. The default is 5000 ms.
+ - `version`, the SNMP version to use. `0` is Version 1, `1` is Version 2c. The default is Version 1 (`0`).
+ - `transport`, the default is `udp4`.
+ - `port`, the port of the SNMP device to connect to. The default is `161`.
+ - `retries`, the number of attempts to make to fetch the data. The default is `1`.
+
+## Retrieving names from snmp
+
+You can append a value retrieved from SNMP to the title, by adding `titleoid` to the chart.
+
+You can set a dimension name to a value retrieved from SNMP, by adding `oidname` to the dimension.
+
+Both of the above will participate in `multiply_range`.
+
+
+## Testing the configuration
+
+To test it, you can run:
+
+```sh
+/usr/libexec/netdata/plugins.d/node.d.plugin 1 snmp
+```
+
+The above will run it on your console and you will be able to see what netdata sees, but also errors. You can get a very detailed output by appending `debug` to the command line.
+
+If it works, restart netdata to activate the snmp collector and refresh the dashboard (if your SNMP device responds with a delay, you may need to refresh the dashboard in a few seconds).
+
+## Data collection speed
+
+Keep in mind that many SNMP switches and routers are very slow. They may not be able to report values per second. If you run `node.d.plugin` in `debug` mode, it will report the time it took for the SNMP device to respond. My switch, for example, needs 7-8 seconds to respond for the traffic on 24 ports (48 OIDs, in/out).
+
+Also, if you use many SNMP clients on the same SNMP device at the same time, values may be skipped. This is a problem of the SNMP device, not this collector.
+
+## Finding OIDs
+
+Use `snmpwalk`, like this:
+
+```sh
+snmpwalk -t 20 -v 1 -O fn -c public 10.11.12.8
+```
+
+- `-t 20` is the timeout in seconds
+- `-v 1` is the SNMP version
+- `-O fn` will display full OIDs in numeric format (you may want to run it also without this option to see human readable output of OIDs)
+- `-c public` is the SNMP community
+- `10.11.12.8` is the SNMP device
+
+Keep in mind that `snmpwalk` outputs the OIDs with a dot in front them. You should remove this dot when adding OIDs to the configuration file of this collector.
+
+## Example: Linksys SRW2024P
+
+This is what I use for my Linksys SRW2024P. It creates:
+
+1. A chart for power consumption (it is a PoE switch)
+2. Two charts for packets received (total packets received and packets received with errors)
+3. One chart for packets output
+4. 24 charts, one for each port of the switch. It also appends the port names, as defined at the switch, to the chart titles.
+
+This switch also reports various other metrics, like snmp, packets per port, etc. Unfortunately it does not report CPU utilization or backplane utilization.
+
+This switch has a very slow SNMP processors. To respond, it needs about 8 seconds, so I have set the refresh frequency (`update_every`) to 15 seconds.
+
+```json
+{
+    "enable_autodetect": false,
+    "update_every": 5,
+    "servers": [
+    {
+        "hostname": "10.11.12.8",
+        "community": "public",
+        "update_every": 15,
+        "options": { "timeout": 20000, "version": 1 },
+        "charts": {
+            "snmp_switch.power": {
+                "title": "Switch Power Supply",
+                "units": "watts",
+                "type": "line",
+                "priority": 10,
+                "family": "power",
+                "dimensions": {
+                    "supply": {
+                        "oid": ".1.3.6.1.2.1.105.1.3.1.1.2.1",
+                        "algorithm": "absolute",
+                        "multiplier": 1,
+                        "divisor": 1,
+                        "offset": 0
+                    },
+                    "used": {
+                        "oid": ".1.3.6.1.2.1.105.1.3.1.1.4.1",
+                        "algorithm": "absolute",
+                        "multiplier": 1,
+                        "divisor": 1,
+                        "offset": 0
+                    }
+                }
+            }
+            , "snmp_switch.input": {
+                "title": "Switch Packets Input",
+                "units": "packets/s",
+                "type": "area",
+                "priority": 20,
+                "family": "IP",
+                "dimensions": {
+                    "receives": {
+                        "oid": ".1.3.6.1.2.1.4.3.0",
+                        "algorithm": "incremental",
+                        "multiplier": 1,
+                        "divisor": 1,
+                        "offset": 0
+                    }
+                    , "discards": {
+                        "oid": ".1.3.6.1.2.1.4.8.0",
+                        "algorithm": "incremental",
+                        "multiplier": 1,
+                        "divisor": 1,
+                        "offset": 0
+                    }
+                }
+            }
+            , "snmp_switch.input_errors": {
+                "title": "Switch Received Packets with Errors",
+                "units": "packets/s",
+                "type": "line",
+                "priority": 30,
+                "family": "IP",
+                "dimensions": {
+                    "bad_header": {
+                        "oid": ".1.3.6.1.2.1.4.4.0",
+                        "algorithm": "incremental",
+                        "multiplier": 1,
+                        "divisor": 1,
+                        "offset": 0
+                    }
+                    , "bad_address": {
+                        "oid": ".1.3.6.1.2.1.4.5.0",
+                        "algorithm": "incremental",
+                        "multiplier": 1,
+                        "divisor": 1,
+                        "offset": 0
+                    }
+                    , "unknown_protocol": {
+                        "oid": ".1.3.6.1.2.1.4.7.0",
+                        "algorithm": "incremental",
+                        "multiplier": 1,
+                        "divisor": 1,
+                        "offset": 0
+                    }
+                }
+            }
+            , "snmp_switch.output": {
+                "title": "Switch Output Packets",
+                "units": "packets/s",
+                "type": "line",
+                "priority": 40,
+                "family": "IP",
+                "dimensions": {
+                    "requests": {
+                        "oid": ".1.3.6.1.2.1.4.10.0",
+                        "algorithm": "incremental",
+                        "multiplier": 1,
+                        "divisor": 1,
+                        "offset": 0
+                    }
+                    , "discards": {
+                        "oid": ".1.3.6.1.2.1.4.11.0",
+                        "algorithm": "incremental",
+                        "multiplier": -1,
+                        "divisor": 1,
+                        "offset": 0
+                    }
+                    , "no_route": {
+                        "oid": ".1.3.6.1.2.1.4.12.0",
+                        "algorithm": "incremental",
+                        "multiplier": -1,
+                        "divisor": 1,
+                        "offset": 0
+                    }
+                }
+            }
+            , "snmp_switch.bandwidth_port": {
+                "title": "Switch Bandwidth for port ",
+                "titleoid": ".1.3.6.1.2.1.31.1.1.1.18.",
+                "units": "kilobits/s",
+                "type": "area",
+                "priority": 100,
+                "family": "ports",
+                "multiply_range": [ 1, 24 ],
+                "dimensions": {
+                    "in": {
+                        "oid": ".1.3.6.1.2.1.2.2.1.10.",
+                        "algorithm": "incremental",
+                        "multiplier": 8,
+                        "divisor": 1024,
+                        "offset": 0
+                    }
+                    , "out": {
+                        "oid": ".1.3.6.1.2.1.2.2.1.16.",
+                        "algorithm": "incremental",
+                        "multiplier": -8,
+                        "divisor": 1024,
+                        "offset": 0
+                    }
+                }
+            }
+        }
+    }
+    ]
+}
+```
diff --git a/collectors/node.d.plugin/snmp/snmp.node.js b/collectors/node.d.plugin/snmp/snmp.node.js
new file mode 100644
index 000000000..a051d3d3a
--- /dev/null
+++ b/collectors/node.d.plugin/snmp/snmp.node.js
@@ -0,0 +1,516 @@
+'use strict';
+// SPDX-License-Identifier: GPL-3.0-or-later
+// netdata snmp module
+// This program will connect to one or more SNMP Agents
+//
+
+// example configuration in /etc/netdata/node.d/snmp.conf
+/*
+{
+    "enable_autodetect": false,
+    "update_every": 5,
+    "max_request_size": 50,
+    "servers": [
+        {
+            "hostname": "10.11.12.8",
+            "community": "public",
+            "update_every": 10,
+            "max_request_size": 50,
+            "options": { "timeout": 10000 },
+            "charts": {
+                "snmp_switch.bandwidth_port1": {
+                    "title": "Switch Bandwidth for port 1",
+                    "units": "kilobits/s",
+                    "type": "area",
+                    "priority": 1,
+                    "dimensions": {
+                        "in": {
+                            "oid": ".1.3.6.1.2.1.2.2.1.10.1",
+                            "algorithm": "incremental",
+                            "multiplier": 8,
+                            "divisor": 1024,
+                            "offset": 0
+                        },
+                        "out": {
+                            "oid": ".1.3.6.1.2.1.2.2.1.16.1",
+                            "algorithm": "incremental",
+                            "multiplier": -8,
+                            "divisor": 1024,
+                            "offset": 0
+                        }
+                    }
+                },
+                "snmp_switch.bandwidth_port2": {
+                    "title": "Switch Bandwidth for port 2",
+                    "units": "kilobits/s",
+                    "type": "area",
+                    "priority": 1,
+                    "dimensions": {
+                        "in": {
+                            "oid": ".1.3.6.1.2.1.2.2.1.10.2",
+                            "algorithm": "incremental",
+                            "multiplier": 8,
+                            "divisor": 1024,
+                             "offset": 0
+                        },
+                        "out": {
+                            "oid": ".1.3.6.1.2.1.2.2.1.16.2",
+                            "algorithm": "incremental",
+                            "multiplier": -8,
+                            "divisor": 1024,
+                            "offset": 0
+                        }
+                    }
+                }
+            }
+        }
+    ]
+}
+*/
+
+// You can also give ranges of charts like the following.
+// This will append 1-24 to id, title, oid (on each dimension)
+// so that 24 charts will be created.
+/*
+{
+    "enable_autodetect": false,
+    "update_every": 10,
+    "max_request_size": 50,
+    "servers": [
+        {
+            "hostname": "10.11.12.8",
+            "community": "public",
+            "update_every": 10,
+            "max_request_size": 50,
+            "options": { "timeout": 20000 },
+            "charts": {
+                "snmp_switch.bandwidth_port": {
+                    "title": "Switch Bandwidth for port ",
+                    "units": "kilobits/s",
+                    "type": "area",
+                    "priority": 1,
+                    "multiply_range": [ 1, 24 ],
+                    "dimensions": {
+                        "in": {
+                            "oid": ".1.3.6.1.2.1.2.2.1.10.",
+                            "algorithm": "incremental",
+                            "multiplier": 8,
+                            "divisor": 1024,
+                            "offset": 0
+                        },
+                        "out": {
+                            "oid": ".1.3.6.1.2.1.2.2.1.16.",
+                            "algorithm": "incremental",
+                            "multiplier": -8,
+                            "divisor": 1024,
+                            "offset": 0
+                        }
+                    }
+                }
+            }
+        }
+    ]
+}
+*/
+
+var net_snmp = require('net-snmp');
+var extend = require('extend');
+var netdata = require('netdata');
+
+if(netdata.options.DEBUG === true) netdata.debug('loaded', __filename, ' plugin');
+
+netdata.processors.snmp = {
+    name: 'snmp',
+
+    fixoid: function(oid) {
+        if(typeof oid !== 'string')
+            return oid;
+
+        if(oid.charAt(0) === '.')
+            return oid.substring(1, oid.length);
+
+        return oid;
+    },
+
+    prepare: function(service) {
+        var __DEBUG = netdata.options.DEBUG;
+
+        if(typeof service.snmp_oids === 'undefined' || service.snmp_oids === null || service.snmp_oids.length === 0) {
+            // this is the first time we see this service
+
+            if(__DEBUG === true)
+                netdata.debug(service.module.name + ': ' + service.name + ': preparing ' + this.name + ' OIDs');
+
+            // build an index of all OIDs
+            service.snmp_oids_index = {};
+            var chart_keys = Object.keys(service.request.charts);
+            var chart_keys_len = chart_keys.length;
+            while(chart_keys_len--) {
+                var c = chart_keys[chart_keys_len];
+                var chart = service.request.charts[c];
+
+                // for each chart
+
+                if(__DEBUG === true)
+                    netdata.debug(service.module.name + ': ' + service.name + ': indexing ' + this.name + ' chart: ' + c);
+
+                if(typeof chart.titleoid !== 'undefined') {
+                        service.snmp_oids_index[this.fixoid(chart.titleoid)] = {
+                            type: 'title',
+                            link: chart
+                        };
+                    }
+
+                var dim_keys = Object.keys(chart.dimensions);
+                var dim_keys_len = dim_keys.length;
+                while(dim_keys_len--) {
+                    var d = dim_keys[dim_keys_len];
+                    var dim = chart.dimensions[d];
+
+                    // for each dimension in the chart
+
+                    var oid = this.fixoid(dim.oid);
+                    var oidname = this.fixoid(dim.oidname);
+
+                    if(__DEBUG === true)
+                        netdata.debug(service.module.name + ': ' + service.name + ': indexing ' + this.name + ' chart: ' + c + ', dimension: ' + d + ', OID: ' + oid + ", OID name: " + oidname);
+
+                    // link it to the point we need to set the value to
+                    service.snmp_oids_index[oid] = {
+                        type: 'value',
+                        link: dim
+                    };
+
+                    if(typeof oidname !== 'undefined')
+                        service.snmp_oids_index[oidname] = {
+                            type: 'name',
+                            link: dim
+                        };
+
+                    // and set the value to null
+                    dim.value = null;
+                }
+            }
+
+            if(__DEBUG === true)
+                netdata.debug(service.module.name + ': ' + service.name + ': indexed ' + this.name + ' OIDs: ' + netdata.stringify(service.snmp_oids_index));
+
+            // now create the array of OIDs needed by net-snmp
+            service.snmp_oids = Object.keys(service.snmp_oids_index);
+
+            if(__DEBUG === true)
+                netdata.debug(service.module.name + ': ' + service.name + ': final list of ' + this.name + ' OIDs: ' + netdata.stringify(service.snmp_oids));
+
+            service.snmp_oids_cleaned = 0;
+        }
+        else if(service.snmp_oids_cleaned === 0) {
+            service.snmp_oids_cleaned = 1;
+
+            // the second time, keep only values
+
+            service.snmp_oids = new Array();
+            var oid_keys = Object.keys(service.snmp_oids_index);
+            var oid_keys_len = oid_keys.length;
+            while(oid_keys_len--) {
+                if (service.snmp_oids_index[oid_keys[oid_keys_len]].type === 'value')
+                    service.snmp_oids.push(oid_keys[oid_keys_len]);
+            }
+        }
+    },
+
+    getdata: function(service, index, ok, failed, callback) {
+        var __DEBUG = netdata.options.DEBUG;
+        var that = this;
+
+        if(index >= service.snmp_oids.length) {
+            callback((ok > 0)?{ ok: ok, failed: failed }:null);
+            return;
+        }
+
+        var slice;
+        if(service.snmp_oids.length <= service.request.max_request_size) {
+            slice = service.snmp_oids;
+            index = service.snmp_oids.length;
+        }
+        else if(service.snmp_oids.length - index <= service.request.max_request_size) {
+            slice = service.snmp_oids.slice(index, service.snmp_oids.length);
+            index = service.snmp_oids.length;
+        }
+        else {
+            slice = service.snmp_oids.slice(index, index + service.request.max_request_size);
+            index += service.request.max_request_size;
+        }
+
+        if(__DEBUG === true)
+            netdata.debug(service.module.name + ': ' + service.name + ': making ' + slice.length + ' entries request, max is: ' + service.request.max_request_size);
+
+        service.snmp_session.get(slice, function(error, varbinds) {
+            if(error) {
+                service.error('Received error = ' + netdata.stringify(error) + ' varbinds = ' + netdata.stringify(varbinds));
+
+                // make all values null
+                var len = slice.length;
+                while(len--)
+                    service.snmp_oids_index[slice[len]].value = null;
+            }
+            else {
+                if(__DEBUG === true)
+                    netdata.debug(service.module.name + ': ' + service.name + ': got valid ' + service.module.name + ' response: ' + netdata.stringify(varbinds));
+
+                var varbinds_len = varbinds.length;
+                for(var i = 0; i < varbinds_len ; i++) {
+                    var value = null;
+
+                    if(net_snmp.isVarbindError(varbinds[i])) {
+                        if(__DEBUG === true)
+                            netdata.debug(service.module.name + ': ' + service.name + ': failed ' + service.module.name + ' get for OIDs ' + varbinds[i].oid);
+
+                        service.error('OID ' + varbinds[i].oid + ' gave error: ' + snmp.varbindError(varbinds[i]));
+                        value = null;
+                        failed++;
+                    }
+                    else {
+                        // test fom Counter64
+                        // varbinds[i].type = net_snmp.ObjectType.Counter64;
+                        // varbinds[i].value = new Buffer([0x34, 0x49, 0x2e, 0xdc, 0xd1]);
+
+                        switch(varbinds[i].type) {
+                            case net_snmp.ObjectType.OctetString:
+                                if (service.snmp_oids_index[varbinds[i].oid].type !== 'title' && service.snmp_oids_index[varbinds[i].oid].type !== 'name') {
+                                    // parse floating point values, exposed as strings
+                                    value = parseFloat(varbinds[i].value) * 1000;
+                                    if (__DEBUG === true) netdata.debug(service.module.name + ': ' + service.name + ': found ' + service.module.name + ' value of OIDs ' + varbinds[i].oid + ", ObjectType " + net_snmp.ObjectType[varbinds[i].type] + " (" + netdata.stringify(varbinds[i].type) + "), typeof(" + typeof(varbinds[i].value) + "), in JSON: " + netdata.stringify(varbinds[i].value) + ", value = " + value.toString() + " (parsed as float in string)");
+                                }
+                                else {
+                                    // just use the string
+                                    value = varbinds[i].value;
+                                    if (__DEBUG === true) netdata.debug(service.module.name + ': ' + service.name + ': found ' + service.module.name + ' value of OIDs ' + varbinds[i].oid + ", ObjectType " + net_snmp.ObjectType[varbinds[i].type] + " (" + netdata.stringify(varbinds[i].type) + "), typeof(" + typeof(varbinds[i].value) + "), in JSON: " + netdata.stringify(varbinds[i].value) + ", value = " + value.toString() + " (parsed as string)");
+                                }
+                                break;
+
+                            case net_snmp.ObjectType.Counter64:
+                                // copy the buffer
+                                value = '0x' + varbinds[i].value.toString('hex');
+                                if(__DEBUG === true) netdata.debug(service.module.name + ': ' + service.name + ': found ' + service.module.name + ' value of OIDs ' + varbinds[i].oid + ", ObjectType " + net_snmp.ObjectType[varbinds[i].type] + " (" + netdata.stringify(varbinds[i].type) + "), typeof(" + typeof(varbinds[i].value) + "), in JSON: " + netdata.stringify(varbinds[i].value) + ", value = " + value.toString() + " (parsed as buffer)");
+                                break;
+
+                            case net_snmp.ObjectType.Integer:
+                            case net_snmp.ObjectType.Counter:
+                            case net_snmp.ObjectType.Gauge:
+                            default:
+                                value = varbinds[i].value;
+                                if(__DEBUG === true) netdata.debug(service.module.name + ': ' + service.name + ': found ' + service.module.name + ' value of OIDs ' + varbinds[i].oid + ", ObjectType " + net_snmp.ObjectType[varbinds[i].type] + " (" + netdata.stringify(varbinds[i].type) + "), typeof(" + typeof(varbinds[i].value) + "), in JSON: " + netdata.stringify(varbinds[i].value) + ", value = " + value.toString() + " (parsed as number)");
+                                break;
+                        }
+
+                        ok++;
+                    }
+
+                    if(value !== null) {
+                        switch(service.snmp_oids_index[varbinds[i].oid].type) {
+                            case 'title': service.snmp_oids_index[varbinds[i].oid].link.title += ' ' + value; break;
+                            case 'name' : service.snmp_oids_index[varbinds[i].oid].link.name = value.toString().replace(/\W/g, '_'); break;
+                            case 'value': service.snmp_oids_index[varbinds[i].oid].link.value = value; break;
+                        }
+                    }
+                }
+
+                if(__DEBUG === true)
+                    netdata.debug(service.module.name + ': ' + service.name + ': finished ' + service.module.name + ' with ' + ok + ' successful and ' + failed + ' failed values');
+            }
+            that.getdata(service, index, ok, failed, callback);
+        });
+    },
+
+    process: function(service, callback) {
+        var __DEBUG = netdata.options.DEBUG;
+
+        this.prepare(service);
+
+        if(service.snmp_oids.length === 0) {
+            // no OIDs found for this service
+
+            if(__DEBUG === true)
+                service.error('no OIDs to process.');
+
+            callback(null);
+            return;
+        }
+
+        if(typeof service.snmp_session === 'undefined' || service.snmp_session === null) {
+            // no SNMP session has been created for this service
+            // the SNMP session is just the initialization of NET-SNMP
+
+            if(__DEBUG === true)
+                netdata.debug(service.module.name + ': ' + service.name + ': opening ' + this.name + ' session on ' + service.request.hostname + ' community ' + service.request.community + ' options ' + netdata.stringify(service.request.options));
+
+            // create the SNMP session
+            service.snmp_session = net_snmp.createSession (service.request.hostname, service.request.community, service.request.options);
+
+            if(__DEBUG === true)
+                netdata.debug(service.module.name + ': ' + service.name + ': got ' + this.name + ' session: ' + netdata.stringify(service.snmp_session));
+
+            // if we later need traps, this is how to do it:
+            //service.snmp_session.trap(net_snmp.TrapType.LinkDown, function(error) {
+            //  if(error) console.error('trap error: ' + netdata.stringify(error));
+            //});
+        }
+
+        // do it, get the SNMP values for the sessions we need
+        this.getdata(service, 0, 0, 0, callback);
+    }
+};
+
+var snmp = {
+    name: __filename,
+    enable_autodetect: true,
+    update_every: 1,
+    base_priority: 50000,
+
+    charts: {},
+
+    processResponse: function(service, data) {
+        if(data !== null) {
+            if(service.added !== true)
+                service.commit();
+
+            var chart_keys = Object.keys(service.request.charts);
+            var chart_keys_len = chart_keys.length;
+            for(var i = 0; i < chart_keys_len; i++) {
+                var c = chart_keys[i];
+
+                var chart = snmp.charts[c];
+                if(typeof chart === 'undefined') {
+                    chart = service.chart(c, service.request.charts[c]);
+                    snmp.charts[c] = chart;
+                }
+
+                service.begin(chart);
+
+                var dimensions = service.request.charts[c].dimensions;
+                var dim_keys = Object.keys(dimensions);
+                var dim_keys_len = dim_keys.length;
+                for(var j = 0; j < dim_keys_len ; j++) {
+                    var d = dim_keys[j];
+
+                    if (dimensions[d].value !== null) {
+                        if(typeof dimensions[d].offset === 'number')
+                            service.set(d, dimensions[d].value + dimensions[d].offset);
+                        else
+                            service.set(d, dimensions[d].value);
+                    }
+                }
+
+                service.end();
+            }
+        }
+    },
+
+    // module.serviceExecute()
+    // this function is called only from this module
+    // its purpose is to prepare the request and call
+    // netdata.serviceExecute()
+    serviceExecute: function(conf) {
+        var __DEBUG = netdata.options.DEBUG;
+
+        if(__DEBUG === true)
+            netdata.debug(this.name + ': snmp hostname: ' + conf.hostname + ', update_every: ' + conf.update_every);
+
+        var service = netdata.service({
+            name: conf.hostname,
+            request: conf,
+            update_every: conf.update_every,
+            module: this,
+            processor: netdata.processors.snmp
+        });
+
+        // multiply the charts, if required
+        var chart_keys = Object.keys(service.request.charts);
+        var chart_keys_len = chart_keys.length;
+        for( var i = 0; i < chart_keys_len ; i++ ) {
+            var c = chart_keys[i];
+            var service_request_chart = service.request.charts[c];
+
+            if(__DEBUG === true)
+                netdata.debug(this.name + ': snmp hostname: ' + conf.hostname + ', examining chart: ' + c);
+
+            if(typeof service_request_chart.update_every === 'undefined')
+                service_request_chart.update_every = service.update_every;
+
+            if(typeof service_request_chart.multiply_range !== 'undefined') {
+                var from = service_request_chart.multiply_range[0];
+                var to = service_request_chart.multiply_range[1];
+                var prio = service_request_chart.priority || 1;
+
+                if(prio < snmp.base_priority) prio += snmp.base_priority;
+
+                while(from <= to) {
+                    var id = c + from.toString();
+                    var chart = extend(true, {}, service_request_chart);
+                    chart.title += from.toString();
+
+                    if(typeof chart.titleoid !== 'undefined')
+                        chart.titleoid += from.toString();
+
+                    chart.priority = prio++;
+
+                    var dim_keys = Object.keys(chart.dimensions);
+                    var dim_keys_len = dim_keys.length;
+                    for(var j = 0; j < dim_keys_len ; j++) {
+                        var d = dim_keys[j];
+
+                        chart.dimensions[d].oid += from.toString();
+
+                        if(typeof chart.dimensions[d].oidname !== 'undefined')
+                            chart.dimensions[d].oidname += from.toString();
+                    }
+                    service.request.charts[id] = chart;
+                    from++;
+                }
+
+                delete service.request.charts[c];
+            }
+            else {
+                if(service.request.charts[c].priority < snmp.base_priority)
+                    service.request.charts[c].priority += snmp.base_priority;
+            }
+        }
+
+        service.execute(this.processResponse);
+    },
+
+    configure: function(config) {
+        var added = 0;
+
+        if(typeof config.max_request_size === 'undefined')
+            config.max_request_size = 50;
+
+        if(typeof(config.servers) !== 'undefined') {
+            var len = config.servers.length;
+            while(len--) {
+                if(typeof config.servers[len].update_every === 'undefined')
+                    config.servers[len].update_every = this.update_every;
+
+                if(typeof config.servers[len].max_request_size === 'undefined')
+                    config.servers[len].max_request_size = config.max_request_size;
+
+                this.serviceExecute(config.servers[len]);
+                added++;
+            }
+        }
+
+        return added;
+    },
+
+    // module.update()
+    // this is called repeatidly to collect data, by calling
+    // service.execute()
+    update: function(service, callback) {
+        service.execute(function(serv, data) {
+            service.module.processResponse(serv, data);
+            callback();
+        });
+    }
+};
+
+module.exports = snmp;