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Flexible server monitoring

Ping 1500MTU

Hi,

I need to be able to ping at 1500 MTU size. I created my own "Ping 1500MTU" service which works fine but doesn't give me the flexibility to adjust the failure rate before an alarm. I want to be able to have the same options as the regular Ping service (Failure if > 2000ms or Packet Loss over 20%). Does anyone know how I can do this?

Thank you.

David Sinclair's picture

Re: Ping 1500MTU

You'd need to use grep or similar to analyze the ping results in your script, and output suitable failure results.

If a number of people think it'd be useful to add a packet size option for the default Ping service, I could add that to the feature ideas list for a future version.

Re: Ping 1500MTU

It would be very handy - many people do not know that this is a big issue already for fiber connections are instead of copper. Copper is limited in the hardware CPEs however, fiber CPEs are not and can run true ethernet and jumbo packets.

David Sinclair's picture

Re: Ping 1500MTU

I guess Wi-Fi has a similar limit? I have a fiber connection (Verizon Fios) but am currently on AirPort. When I try ping in Terminal with various sizes, the maximum number of bytes I can send is 1464:

% ping -c5 -s1464 dejal.com
PING dejal.com (74.54.103.88): 1464 data bytes
1472 bytes from 74.54.103.88: icmp_seq=0 ttl=50 time=79.237 ms
1472 bytes from 74.54.103.88: icmp_seq=1 ttl=50 time=79.068 ms
1472 bytes from 74.54.103.88: icmp_seq=2 ttl=50 time=78.736 ms
1472 bytes from 74.54.103.88: icmp_seq=3 ttl=50 time=78.384 ms
1472 bytes from 74.54.103.88: icmp_seq=4 ttl=50 time=80.558 ms

--- dejal.com ping statistics ---
5 packets transmitted, 5 packets received, 0.0% packet loss
round-trip min/avg/max/stddev = 78.384/79.197/80.558/0.741 ms

% ping -c5 -s1465 dejal.com
PING dejal.com (74.54.103.88): 1465 data bytes
Request timeout for icmp_seq 0
Request timeout for icmp_seq 1
Request timeout for icmp_seq 2
Request timeout for icmp_seq 3

--- dejal.com ping statistics ---
5 packets transmitted, 0 packets received, 100.0% packet loss

David Sinclair's picture

Re: Ping 1500MTU

Version 3.3 includes a change to enable specifying the number of bytes.