Know your servers and network devices still answer

Some systems have no web page to check: a mail server, a VPN gateway, a router at a branch office, a database host, the uplink of a data centre rack. The first sign that one is gone should not be a colleague saying the connection is down. An ICMP ping — the same one you would type in a terminal — is the simplest way to know that a host is reachable at all.

What the check does

Each check sends one ICMP echo request to the host and waits for the reply. It records whether the host answered and how long the answer took, from each location you choose. The round-trip time is charted, so you can see a route that got slower over the last week, not only a host that stopped answering.

Hostnames are resolved on every check, so a DNS change is followed automatically.

How a failure is judged

One echo request per check means one lost packet is one failed check. That is why the alert threshold matters: "3 of the last 5 checks failed" ignores a single lost packet and reports a host that is really down. The threshold is applied per location, so a host that is unreachable from one region is not hidden by the others.

Why use Pingsured for ping monitoring

From outside your network. A check from your own network says nothing about whether customers or branch offices can reach you. Ours run from Germany, Finland, the US West Coast and Singapore.
Easy to allow through a firewall. Our checks come from published addresses, so you can let exactly those through and keep ICMP closed to everyone else.
Next to your other checks. A server's ping, its TLS certificate and the web application on it, on one dashboard and with the same alerts.
Monitoring data stays in the EU. The list of your hosts is a map of your infrastructure; Pingsured stores it in Germany and Finland.

Limits worth knowing

Only public addresses can be checked. Hosts in a private network — 10.x, 192.168.x and the like — are refused.
A check is one echo request, so there is no packet-loss percentage or jitter figure; the history of failed and passed checks is the measure.
Many hosts and providers drop ICMP on purpose. For a web server, an HTTP or TLS check says more about whether it works; a ping says only that the machine answers.