ICMP method
General
The ICMP method relates to the ICMP protocol which is usually the standard protocol for a simple ping request. A single measurement sends a ICMP packet to the specified IP address or hostname and measures the round-trip-time.
When to use the ICMP method
ICMP requests are very useful to monitor the availability of a host/device/server as usually every host is answering to an ICMP request. ICMP packets are lightweight and fast and therefore don't produce a high load on the client or the target host. Not only the availability but also the round-trip-time (latency) to a host can be measured. High latencies to a host indicate performance issues for a client that can be caused by high loads (in the network or on the host) or indicate misconfigurations.
Parameters
These are the parameters that are configurable for each test using the ICMP method.
IP address or hostname
The target host of the ICMP requests. Either a local or global IP address can be specified or a hostname that will be resolved to the corresponding IP address.
Examples: 192.168.2.1, weibo.com
Number of executions
The number of ICMP packets send per minute. To measure the availability one request is sufficient. To measure the performance a value between 3 and 10 measurements is recommended.
Allowed inputs: 1 - 58
Example: 10
Warning threshold
The threshold defines the latency beyond which a measurement gets the status warning. A senseful threshold highly depens on the proximity of the target, e.g. whether it is internal or external. An ICMP request times out after 1s.
Base value (internal): 50ms
Base value (external): 100ms
Allowed input: 1 - 1.000 and has to be less than the critical threshold.
Critical threshold
The threshold defines the latency beyond which the measurement gets the status crticial. As for the warning threshold, a sensful value depens on the proximity of the target. An ICMP request times out after 1s.
Base value (internal): 100ms
Base value (external): 150ms
Allowed input: 1 - 1.000 and has to be greater than the warning threshold.
Status percentage
See Status percentage. One or two slow ICMP packets per test run are normal and generally not noticeable for the performance.
Allowed input: 1 - 100.
Limitations and recommondations
- The host needs to respond to ICMP packets. Make sure your target host does not block this.
Example test
Microsoft Connect Test