Create a NAM monitor

With network availability monitors (NAM), you can check the availability of your hosts, devices, and services.

There are three types of NAM monitors: ICMP, TCP, and DNS. To learn more about them, see NAM types. You can create NAM monitors in Synthetic in latest Dynatrace or through API.

Configuration

With NAM monitors, you can include more than one step.

  • Each step can contain one or multiple requests.
  • Like for HTTP and browser monitors, steps are executed sequentially.
  • Unlike for HTTP and browser monitors, NAM monitors can contain multiple requests within a single step. All requests assigned to a particular step are executed in parallel. If one request fails, it doesn't affect the execution of other requests within that step.
  • Concept of requests executed in parallel exists for NAM monitors only

For example, if you want to monitor a group of 4 hosts with an ICMP test, you want to apply the same conditions (such as frequency, location executing test, and number of packets) for each host from your group.

NAM offers you the possibility of addressing this in multiple ways:

  • You can define 4 separate tests, one per host. The benefit of this approach is that Dynatrace triggers a separate problem for each host and you can assign separate notifications for each one. You can also adjust test parameters for each host separately.

  • You can define a single test with 4 requests (within 1 step). The same ICMP checks are executed, but there will be differences in reporting and alerting. The number or percentage of hosts that are down is reported with the Requests Success rate metric. You can configure a customized threshold for failing the whole monitor. For example, if it's OK that 1 out of 4 hosts is down, because of rolling out an update, you can define it on the >=75% level. There's always a single problem generated for a monitor, yet still, it contains detailed info about hosts that don't respond. Another benefit of this approach is easier maintenance (adjusting single setting for all 4 hosts).

    Finally, filters offer defining tests against dynamically changing structure, for example if you want to define ICMP tests against a given host group, you don't need to adjust the NAM monitor test after the host group configuration change.

You need to define constraints for each monitor. Constraints are conditions that need to be met to consider the monitor’s execution successful. It is obligatory to define the Success rate constraint. See step-level constraints to learn more.

Create a NAM monitor

To create a NAM monitor in latest Dynatrace

  1. Go to Synthetic and select Create monitor.
  2. Follow the on-screen steps as outlined in the sections below.

Select type

The Create synthetic monitor page shows the types of synthetic monitor you can create.

Select Network monitor (NAM) to get started.

General

  • required Name this monitor—The name of the monitor as it will be displayed in the web UI (up to 500 characters).
  • required Select a protocol—Choose the monitor type: DNS, ICMP, or TCP.
  • optional Set a description—Describe your monitor.
  • optional Add tags to this monitor—To manually create a new tag, select Add tag, type the key, optionally provide a value, and select Add.

After you specify the general settings, select Continue.

Requests

The Requests section has two editing modes. You can switch back and forth between these modes.

  • default Visual—to view and configure NAM requests through web UI settings.
  • Script—to view and edit request settings as JSON. The script you provide also serves as payload for API requests.

Settings per request (you can add multiple requests) are:

  • required Request name—The name of the request.
  • required List of targets or Filter expression
    • You can provide targets for requests as an explicit list, or filter monitored hosts using a filter expression. You can also use a combination of both to fine-tune your selection.
      • If you want to provide targets as IP or domain names, use List of targets to specify a comma-separated list of targets. Use this to monitor single or multiple hosts, devices, or services.
      • If you want to select some of the monitored hosts, use Filter expression to specify a filter expression. This allows you to monitor a group of hosts that meet the filter criteria. To learn more about available filters, see target filter.
  • required Execution attributes—Execution attributes are essentially key/value pairs that are associated with your request. Define Request timeout, Number of packets, Data length, Time to live, Timeout to reply, you can also turn on or turn off Do not fragment data. Execution attributes are available for ICMP only.
  • required Constraints—Constraints are conditions that need to be met to consider monitor’s execution successful. You need to define Constraint type, Operator and value.

If you want to create another request, select Add next request and specify the above for the next request.

Use Duplicate Duplicate to duplicate a request and then edit it from that point instead of starting from scratch each time you add a request.

After you specify all requests, select Continue.

Frequency and locations

In the Frequency and locations section, specify the frequency and locations.

  • required Select frequency—You can choose a frequency (every 1 min, 2 min, 5 min, 10 min, 15 min, 30 min, or 1 h) or select On demand only for manual execution.
  • required n selected locations—Specify one or more locations.

After you specify the frequency and locations, select Continue.

Outage and Performance

In Outage handling, you can enable and configure the following settings related to problem and alert generation:

  • optional "Generate a problem and send an alert when the monitor is unavailable at all configured locations (global outage)."
  • optional "Generate a problem and send an alert when the monitor is unavailable only when at least two locations are assigned." Note that this option is only possible if you selected two or more locations.
  • optional "Generate a problem and send an alert on performance threshold violations."

After you specify the outage and performance settings, select Continue.

Summary

In the Summary section, verify your settings.

After you review the summary, select Save to create your monitor or Back to go back and adjust your monitor settings.

Target filter

Target filter gives an option to filter hosts monitored by Dynatrace or custom devices having IP addresses. With this filter, you can select those two types of targets based on:

  • type (type)
  • tags (tag)
  • host ID (hostId) (deprecated, works for hosts only, use entity ID instead)
  • entity ID (entityId)
  • host groups (hostGroup)
  • management zones (managementZone)
  • IP mask (ipMask)
  • IP range (ipRange)
  • process group instance (processGroupInstance)
  • network interfaces of particular custom device (interfacesOf)
  • extension name (extensionName)

IP range and IP mask are filters for hosts known for the Dynatrace server, not an option to scan the network.

Syntax

  • Logical operators: AND and OR (case insensitive)
  • Parentheses
  • Expression operators: == and !=
  • Tag names and values
  • Negation ("not"): !=.
  • Wildcard: * (selects all hosts monitored by Dynatrace)

Examples

  • tag == tagname or hostGroup == group1
  • (tag == tagname1:tagvalue1 or tag == tagname1:tagvalue2) and (hostGroup == group1 or managementZone == zone1)
  • tag != tagname1 and tag != tagname2:tagvalue
  • tag == tagname:tagvalue and (managementZone == zone1 or managementZone == zone2)
  • tag == "[tagwithbrackets and spaces]":"value, with, commas, and, spaces"
  • ipMask == 127.0.0.1/24
  • hostId == HOST-000123
  • type == CUSTOM_DEVICE and ipMask == 172.17.0.2/24
  • entityId == HOST-045BFCDA3F507D30 or entityId == CUSTOM_DEVICE-13081D4B74B3E2C8
  • type == HOST and processGroupInstance == PROCESS_GROUP_INSTANCE-07611353BB98908C
  • type == CUSTOM_DEVICE and interfacesOf == CUSTOM_DEVICE-E1A88946BF04D5E7
  • type == CUSTOM_DEVICE and extensionName == "Docker devices"

Performance thresholds

The performance threshold metric is compared to metric calculated for each request within monitor/step. For example, if TCP port check monitor, tests on the same host port 80 and 443 separately, Dynatrace compares threshold TCP connection establishment time twice, once for port 80 and once for port 443.

There are three performance metrics for three types of NAM monitors:

  • RTT for ICMP
  • TCP connection establishment time for TCP
  • DNS resolution time for DNS

Violating defined performance triggers a Problem (Slowdown).

Similarly to availability problems:

  • Problems are opened per monitor
  • Contains information about all requests responsible for problem

You can configure the way Dynatrace aggregates results for each packet for ICMP requests with single execution. Dynatrace supports AVG, MAX and MIN with AVG as the default method.

Define thresholds

You can define performance thresholds when configuring the request for your synthetic monitor. The defined performance threshold is the same for all requests within a single step. In cases, where there's a need to build a multi-step NAM monitor, it's possible to define various thresholds for each step.

To define thresholds

  1. Follow the steps described in Create a NAM monitor section.

  2. In the Requests step, scroll down the page and see Performance thresholds alerting section.

  3. Select Generate a problem and send an alert on performance threshold violations. check box.

  4. Turn on Advanced performance thresholds settings toggle.

    In this section you can set the Number of request executions in analyzed sliding window and the Number of violating request executions in analyzed sliding window. For de-alerting samples we require n most recent non-violating request executions.

Violation reporting

Red color annotation over performance charts indicates the period of time during which the performance threshold is raised. Additionally, a threshold is drawn on the performance chart, and you can examine which requests are above the threshold.

You may narrow down the time range only to that for which the problem was active using zoom functionality.

Manage NAM monitors with API

To manage your NAM monitors via REST API

  1. Search for and select Dynatrace API.

  2. In the Select a definition field, select Synthetic - Network availability monitors.

  3. Authenticate with your API token.

    For details, see Authentication.

  4. Perform one of the following actions.

    To do this
    Go to Synthetic - Network availability monitors and select this
    Get all synthetic monitors
    GET /synthetic/monitors
    Create a synthetic monitor definition
    POST /synthetic/monitors
    Delete a synthetic monitor definition for the given monitor ID
    DELETE /synthetic/monitors/{monitorId}
    Get all synthetic monitor definition for the given monitor ID
    GET /synthetic/monitors/{monitorId}
    Update a synthetic monitor definition for the given monitor ID.
    PUT /synthetic/monitors/{monitorId}

See Synthetic monitors API v2 for more details.

Available script configuration properties

optional

Monitors consist of requests, always of the same type (ICMP, TCP, or DNS).

If you don't provide the value, defaults will apply.

  • 100 milliseconds = PT0.1S
  • 500 milliseconds = PT0.5S
  • 1 second = PT1S
  • 10 seconds = PT10S
  • 90 seconds = PT1M30S
  • 1 minute = PT1M
  • 2 minutes = PT2M
  • 5 minutes = PT5M

ICMP

Name

Type

Description

Values

Default value

EXECUTION_TIMEOUT

string:duration

Timeout for the execution of a single request.

Valid duration, for example, PT1S.

Range = 0PT2M

ICMP_NUMBER_OF_PACKETS × ICMP_TIMEOUT_FOR_REPLY + 1s

ICMP_NUMBER_OF_PACKETS

integer

Number of echo requests. The equivalent of the ping process are the -c (Linux) and -n (Windows) parameters.

Range = 110

1

ICMP_PACKET_SIZE

integer

Data length. The equivalent of the ping process are the -s (Linux) and -l (Windows) parameters.

Range = 065500

32

ICMP_TIME_TO_LIVE

integer

Time to live (TTL). The equivalent of the ping process are the -t (Linux) and -i (Windows) parameters.

Range = 1255

ICMP_TYPE_OF_SERVICE

integer

Type of service. The equivalent of the ping process are the -Q (Linux) and -v (Windows) parameters.

Range = 0255

ICMP_DO_NOT_FRAGMENT_DATA

boolean

Do not fragment. The equivalent of the ping process are the -M do (Linux) and -f (Windows) parameters.

true or false

ICMP_TIMEOUT_FOR_REPLY

string:duration

Wait for the echo reply message.

The equivalent of the ping process are the -W (Linux) and -w (Windows) parameters.

Valid duration, for example, PT1S. On Windows values like PT1.1S are accepted (granularity in milliseconds).

On Linux, values like PT1S are required (granularity in seconds).

Range = PT1SPT2S

PT1S

TCP

Name

Type

Description

Values

Default value

TCP_PORT_RANGES

string

Comma-separated list of port ranges

A single range can be either a single port number or a range of ports, defined as two port numbers with a hyphen.

The final list of requests to be executed is the product of all defined ports and target hosts. For example, if a step has two target hosts (1.1.1.1 and 2.2.2.2) and a range of two ports (80-81), four requests are executed within such a step.

  • Request to 1.1.1.1 on port 80
  • Request to 1.1.1.1 on port 81
  • Request to 2.2.2.2 on port 80
  • Request to 2.2.2.2 on port 81

Sample values

  • 8080
  • 8000-9000
  • 80,443,90-100

EXECUTION_TIMEOUT

string:duration

Connection timeout

Valid duration, for example, PT1S

Range = 0PT2M

1s

DNS

Name

Type

Description

Values

Default value

DNS_RECORD_TYPES

string

Comma-separated list of DNS record types.

The final list of requests executed is the product of all defined record types and target hosts. For example, if a step has two record types (A,AAAA) and two target hosts (host1.domain.com and host2.domain.com), four requests are executed within such a step.

  • Request for A record contents for host1.domain.com
  • Request for AAAA record contents for host1.domain.com
  • Request for A record contents for host2.domain.com
  • Request or AAAA record contents for host2.domain.com

Sample values

  • A
  • A,AAAA
  • A,AAAA,CNAME

EXECUTION_TIMEOUT

string:duration

Connection timeout

Valid duration, for example, PT1S

Range = 0PT2M

2s

DNS_SERVER

string

Address of the DNS server to query, with optional port

If a hostname is provided, it's resolved to an IP address using the system default DNS server.

Valid address, such as:

  • 1.1.1.1
  • 8.4.4.8:53
  • dns.google
  • dns9.quad9.net:53

If only host is provided, the default port 53 is used.

If no value is provided, the system default DNS server and port are used.

DNS_FORCE_TCP

boolean

By default, the DNS server is queried over a UDP connection, unless the message is too large to fit the UDP datagram. This option allows you to specify a TCP connection instead.

true or false

false

Script configuration constraints

Constraints are conditions that need to be met to consider monitor’s execution successful. You need to define constraints for each monitor.

Step-level constraints

SUCCESS_RATE_PERCENT

required

This is an obligatory constraint for all monitors' request success rate. The default value is >=80%.

Percentage of successful requests in a step.

Actual success rate = ratio of the number of requests that didn't fail to all requests.

For example, if 1 request out of 6 has failed, the ratio is (6-1)/6 = 83.33%.

Property
Type
Description
Value
Default value
operator
string
Comparison operator to compare actual and expected value
>=, >, <=, <, =, or !=
>=
value
integer
Expected value of success rate to use for comparison
Range = 0100
80
{
"type": "SUCCESS_RATE_PERCENT",
"properties": {
"value": "80",
"operator": ">"
}
}

For requests with only one target, we suggest setting the constraints values to 100.

Request-level constraints

ICMP request constraints

ICMP_SUCCESS_RATE_PERCENT

required

This is an obligatory constraint for ICMP monitors request success rate. The default value is >=80%.

Percentage of successful pings (echo requests) in a request.

Actual success rate = ratio of number of the packets received to number of packets sent.

For example, if 5 packets were sent and 4 packets were received, the ratio is 4/5 = 80.00%.

Property
Type
Description
Value
Default value
operator
string
Comparison operator to compare actual and expected value
>=, >, <=, <, =, or !=
>=
value
integer
Expected value of success rate to use for comparison
Range = 0100
80
{
"type": "ICMP_SUCCESS_RATE_PERCENT",
"properties": {
"value": "80",
"operator": ">"
}
}

TCP request constraints

TCP_PORT_UNREACHABLE

optional

This is an optional constraint for TCP monitors. This is a special constraint that inverts the execution status for TCP requests. It should be applied if it's expected that the port being checked is unreachable.

This constraint has no configuration properties.

If this constraint is applied:

  • When the Execution timeout (12033) and TCP socket connection error (22000) statuses are detected after performing a connection attempt, they are interpreted as HEALTHY (0).
  • The HEALTHY (0) connection status is interpreted as CONSTRAINT_VIOLATED (1401) because we expected a failure.
  • The UNEXPECTED_ERROR (-1) and UNKNOWN_HOST (12013) statuses are preserved and reported as is.
{
"type": "TCP_PORT_UNREACHABLE",
"properties": {}
}

DNS request constraints

At least one required

DNS constraints are optional, but at least one must be defined to indicate what is a successful query.

DNS_STATUS_CODE

DNS_STATUS_CODE by default is 1, having status code =0 is the simplest example of a successful query.

Property
Type
Description
Value
Default value
operator
string
Comparison operator to compare actual and expected value
= or !=
=
statusCode
integer
Numeric code indicating status of DNS response
Exclusive with status
Valid code, for example, 0
Range = 065535
0
status
string
Mnemonic representing DNS status code
Exclusive with statusCode
Valid status, for example, NOERROR
NOERROR
{
"type": "DNS_STATUS_CODE",
"properties": {
"operator": "=",
"statusCode": "0"
}
}
{
"type": "DNS_STATUS_CODE",
"properties": {
"operator": "=",
"status": "NOERROR"
}
}
DNS_IP_ADDRESS

Verifies the IP address value returned in A/AAAA records.

Property
Type
Description
Value
Default value
quantifier
string
How many records must match the condition for the constraint to pass
any (at least one) or all
any
operator
string
Comparison operator
=, != or in
= for an address, in for a subnet
recordType
string
DNS record type
A or AAAA
A if address/subnet is IPv4
AAAA if address/subnet is IPv6
address
string
IPv4 address in dot notation or IPv6 address in colon notation
Only with the operators =, !=
Exclusive with subnet
Valid address, for example, 192.168.0.1, 2001:db8::2:1
subnet
string
IPv4 subnet in dot notation or IPv6 subnet in colon notation, followed by network prefix length
Only with the operator in
Exclusive with address
Valid subnet, for example, 172.22.80.0/20, 2001:db8:85a3::0/48
{
"type": "DNS_IP_ADDRESS",
"properties": {
"quantifier": "any",
"recordType": "A",
"operator": "=",
"address": "54.208.9.71"
}
}
{
"type": "DNS_IP_ADDRESS",
"properties": {
"quantifier": "all",
"recordType": "A",
"operator": "in",
"subnet": "10.102.44.0/24"
}
}
DNS_RECORD_COUNT

Verifies the count of records of a given type.

Property
Type
Description
Value
Default value
operator
string
Comparison operator
>=, >, <=, <, =, or !=
>
recordType
string
DNS record type
Valid record type, for example, MX
value
integer
Expected record count
Valid count, for example 2 Range = 065535
80
{
"type": "DNS_RECORD_COUNT",
"properties": {
"recordType": "A",
"operator": ">",
"value": "80"
}
}
DNS_TIME_TO_LIVE

Verifies the time to live (TTL) of records of a given type.

Property
Type
Description
Value
Default value
quantifier
string
How many records must match the condition for the constraint to pass
any (at least one) or all
any
operator
string
Comparison operator
>=, >, <=, <, =, or !=
>
recordType
string
DNS record type
Valid record type, for example, NS
value
integer
Expected TTL in seconds
Valid TTL, for example 3600 Range = 02147483647
80
{
"type": "DNS_TIME_TO_LIVE",
"properties": {
"quantifier": "any",
"recordType": "A",
"operator": ">=",
"value": "80"
}
}
DNS_RECORD_VALUE

Verifies the raw value of records of a given type, with the value format depending on the record type.

Constraints process all records in a response, regardless of the section to which they belong (answer, authority, or additional).

Property
Type
Description
Value
Default value
quantifier
string
How many records must match the condition for the constraint to pass
any (at least one) or all
any
operator
string
Comparison operator
- contains checks if the record value contains a given sequence.
- matches checks if record value matches a given pattern.
contains or matches
contains
recordType
string
DNS record type
Valid record type, for example, TXT
sequence
string
Sequence of characters that the record value should contain
Only with the operator contains
Exclusive with pattern
Non-empty sequence, for example, ms71815323
pattern
string
Pattern to be matched against the record value, with * denoting 0 or more characters
Only with the operator matches
Exclusive with sequence
Non-empty pattern, for example, "v=spf1 include:*
{
"type": "DNS_RECORD_VALUE",
"properties": {
"quantifier": "any",
"recordType": "TXT",
"operator": "contains",
"sequence": "ms71815323"
}
}
{
"type": "DNS_RECORD_VALUE",
"properties": {
"quantifier": "any",
"recordType": "TXT",
"operator": "matches",
"pattern": "\"v=spf1 include:*"
}
}