sys-cmd ping

sys-cmd ping sends an ICMP echo request to a target from the route table selected in WEB-CLI and shows the round-trip time of every response that returns, and at the end the number of packets sent and received together with the loss rate. It is the first step of the question "Is this address reachable over the network, and with how much latency?".

Command Summary

TR7 WEB-CLI · sys-cmd ping

# type ping and press Tab: a free parameter

admin@TR7LBWAF01> sys-cmd ping

<ping-parameter-1>

 

admin@TR7LBWAF01> sys-cmd ping <parameters> <target>

admin@TR7LBWAF01>  

Everything written after the word ping is passed to the tool as it is. There is no mandatory field; the target address or name is written together with the parameters according to the tool's own syntax.

How It Works

Subject	Behavior
Context	The packets are sent from within the selected v-device and route table. For a target in an isolated route table, route-table set is run first.
Duration	If -c is not given, it sends packets without stopping.
Stopping	Ctrl+C stops the tool. If the tool does not close within 10 seconds, it is terminated by force.
Pipe	The output can be filtered with | or written to a file with to-file.
Recording	Every run is written to the user logs.

Frequently Used Parameters

Parameter	What it does	What is written after it
-c	Limits the number of packets to be sent; when this number is reached, the tool closes by itself	A number (e.g. 4)
-i	Changes the waiting time between two packets	Seconds (e.g. 0.2)
-W	Determines how long at most to wait for each response	Seconds
-s	Changes the size of the data section of the packet	Bytes (e.g. 1472)
-M	Determines the fragmentation behavior; do forbids fragmentation and reveals the MTU limit	do · dont · want
-I	Selects the interface from which the packet will go out or the source address	An interface name or an IP address
-q	Does not write the packet-by-packet lines, shows only the summary at the end	—

The table summarizes frequently used parameters; the full list and behavior depend on the version of the tool on the device.

Examples

TR7 WEB-CLI · A) Four packets to the backend

admin@TR7LBWAF01> sys-cmd ping -c 4 10.20.0.15

admin@TR7LBWAF01>  

TR7 WEB-CLI · B) Loss and jitter at short intervals

# 200 ms apart, 20 packets, summary only

admin@TR7LBWAF01> sys-cmd ping -c 20 -i 0.2 -q 10.20.0.15

admin@TR7LBWAF01>  

TR7 WEB-CLI · C) The MTU limit

# 1472 bytes of data + 28 bytes of header = 1500; fragmentation forbidden

admin@TR7LBWAF01> sys-cmd ping -c 3 -s 1472 -M do 10.20.0.15

admin@TR7LBWAF01>  

TR7 WEB-CLI · D) From a specific source address

admin@TR7LBWAF01> sys-cmd ping -c 4 -I 10.20.0.2 10.20.0.15

admin@TR7LBWAF01>  

TR7 WEB-CLI · E) Write only the summary to a file

admin@TR7LBWAF01> sys-cmd ping -c 50 -q 10.20.0.15 | tail -n 2 | to-file ping-summary.txt

admin@TR7LBWAF01>  

Things to Know

• ICMP succeeds but the service is not working. The problem is not in the network but in the service port; it is tested at the port level with nmap, telnet or curl.
• There is no response. The target or a firewall in between may be blocking ICMP; this does not mean that the service is down. Where the path is cut is seen with traceroute.
• The wrong context. If the target is in an isolated route table, a test made from the default context fails misleadingly; the current context is verified with route-table show.
• For IPv6 targets ping6 is used, and for more than one target fping.