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go-ping / ping

ICMP Ping library for Go
MIT License
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How to send packets larger than 1490 #135

Closed QQ2017 closed 3 years ago

QQ2017 commented 3 years ago

How to send packets larger than 1490 on the windows platform?

CHTJonas commented 3 years ago

The docs list the Size field which is what you want:

pinger, _ := ping.NewPinger("1.1.1.1")
pinger.Count = 3
pinger.Size = 1490
pinger.SetPrivileged(true)
pinger.Run()
fmt.Println(pinger.Statistics())

That being said, I wouldn't set a Size that's bigger than 1472 because otherwise you'll likely go over your network MTU and cause packet fragmentation. 1472-byte ICMP message + 8-byte message header + 20-byte IP header = 1500 ethernet MTU. Note that this isn't a hard & fast rule and that your network MTU may be lower, for example if your connection uses PPPoE.

I've just had a look at the code and there is a bug in the deserialisation of ICMP messages larger than 512 bytes; I'll open a separate ticket for that.