ping
Overview
ping sends ICMP echo requests to test reachability and round-trip time. First tool for “is the host up / is the network path alive?”.
Syntax
ping [options] destinationCommon Options
| Option | Description |
|---|---|
-c N |
Count then exit |
-i sec |
Interval |
-W sec |
Wait for reply |
-w sec |
Overall deadline |
-s size |
Payload size |
-M do |
DF bit (PMTU probe) |
-4 / -6 |
Force family |
-n |
No reverse DNS |
-q |
Quiet summary |
Examples with Explanations
ping -c 4 1.1.1.1
ping -c 4 example.com
ping -c 10 -i 0.2 192.168.1.1
ping -c 3 -W 1 10.0.0.1
ping -6 -c 4 2606:4700:4700::1111
ping -M do -s 1472 example.com # DF PMTU experimentsScript-friendly
if ping -c 1 -W 2 gateway >/dev/null; then echo up; else echo down; fiNotes
- ICMP may be blocked while TCP works — try
curl/nctoo.
- Privileges: unprivileged ping works on modern Linux via socket flags; very low intervals may need root.
- High packet size tests fragmentation/PMTU issues.