Its an ESP32 Steve; but an (almost) identical system, with the same code (presently at 192.168.1.42) DOES ping;
the board provides a webpage using server side events; and keeps a log of pings and mains failures that I can access via FTP. It all works fine.
The SimplePing example on an ESP8266 (at 192.168.1.59) DOES ping it; and I've added a line
int avg_time_ms = Ping.averageTime();
to show the time - around 50 - 150ms; and put the ping in the loop() to do it repeatedly at 10 sec intervals. rock solid, no fails.
but as already said testing yesterday a laptop, a linux box, and my android tablet connecting via wifi all get "device unobtainable".
I cant make ANY sense of any of all that!
arp - a on the (wifi) laptop doesnt even SHOW .34, but .42 is there.
Testing again just now on the linux box (at 192.168.1.48)
ping 192.168.1.34 I get a few good pings - then "from 192.168.1.48 - device unobtainable"
The solar logger counts interrupts but at present there are none ('cos its dark) so I can rule that out.
Code here
netmonitor.zip (10.0 KB)
Testing from my PC connected via ethernet
C:\Users\john>arp -a
Interface: 192.168.1.11 --- 0x9
Internet Address Physical Address Type
192.168.1.1 d0-c6-5b-cc-34-c4 dynamic
192.168.1.14 54-04-a6-f0-e4-77 dynamic
192.168.1.24 00-18-97-00-b5-ac dynamic
192.168.1.26 24-fd-52-f3-80-c0 dynamic
192.168.1.30 a4-cf-12-ef-6c-a4 dynamic
192.168.1.31 a4-cf-12-ef-61-62 dynamic
192.168.1.34 7c-9e-bd-3a-04-7c dynamic
192.168.1.36 78-32-1b-c6-dd-a9 dynamic
192.168.1.42 24-0a-c4-60-05-78 dynamic
192.168.1.48 70-1a-04-51-a4-38 dynamic
192.168.1.59 d8-bf-c0-11-23-9d dynamic
192.168.1.75 22-31-3b-a0-47-bc dynamic
192.168.1.255 ff-ff-ff-ff-ff-ff static
192.168.2.1 d0-c6-5b-cc-34-c4 dynamic
224.0.0.22 01-00-5e-00-00-16 static
224.0.0.251 01-00-5e-00-00-fb static
224.0.0.252 01-00-5e-00-00-fc static
239.255.255.250 01-00-5e-7f-ff-fa static
255.255.255.255 ff-ff-ff-ff-ff-ff static
C:\Program Files (x86)\Advanced Port Scanner>ping 192.168.1.34
Pinging 192.168.1.34 with 32 bytes of data:
Reply from 192.168.1.34: bytes=32 time=32ms TTL=255
Reply from 192.168.1.34: bytes=32 time=43ms TTL=255
Reply from 192.168.1.34: bytes=32 time=65ms TTL=255
Reply from 192.168.1.34: bytes=32 time=91ms TTL=255
Ping statistics for 192.168.1.34:
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 32ms, Maximum = 91ms, Average = 57ms