I am trying to run the ResolvingHostNames example from the ArduinoMDNS library on the EdgeBox-ESP-100. I am using the boilerplate example code (with my MAC address). The ethernet connection is successful. However, I get a Guru mediation error after entering the hostname to resolve. Here is the serial output. I decoded the Backtrace via the ESP Exception Decoder, which is also given below. Thanks in advance for any help with this issue.
ETH: Local IP is 192.168.0.66
Enter a mDNS host name via the Arduino Serial Monitor to have it resolved.
Do not postfix the name with “.local”
Resolving 'mark-dev-pi
’ via Multicast DNS (Bonjour)…
Guru Meditation Error: Core 1 panic’ed (LoadProhibited). Exception was unhandled.
Core 1 register dump:
PC : 0x42004f34 PS : 0x00060830 A0 : 0x82003cb2 A1 : 0x3fcebbf0
A2 : 0x3fcebc18 A3 : 0x00000000 A4 : 0x3fc951fc A5 : 0x00000000
A6 : 0x3fcec3b4 A7 : 0x00000000 A8 : 0x3c0302ec A9 : 0x0000002e
A10 : 0x3fcecaab A11 : 0x3fcecab2 A12 : 0x000000ff A13 : 0x0000ff00
A14 : 0x00ff0000 A15 : 0xff000000 SAR : 0x00000016 EXCCAUSE: 0x0000001c
EXCVADDR: 0x00000000 LBEG : 0x400556d5 LEND : 0x400556e5 LCOUNT : 0xfffffffb
Backtrace: 0x42004f31:0x3fcebbf0 0x42003caf:0x3fcebc10 0x420048ad:0x3fcebc40 0x4200197f:0x3fcebc80 0x42006845:0x3fcebeb0
ESP Exception Decoder
Sketch: EdgeBox_ESP_100_ResolvingHostNames FQBN: esp32:esp32:Edgebox-ESP-100
Backtrace: 0x42004f31:0x3fcebbf0 0x42003caf:0x3fcebc10 0x420048ad:0x3fcebc40 0x4200197f:0x3fcebc80 0x42006845:0x3fcebeb0
Decoding stack results
0x42004f31: is in IPAddress::IPAddress(unsigned char const*) (C:\Users\MarkWest\AppData\Local\Arduino15\packages\esp32\hardware\esp32\2.0.14\cores\esp32/Printable.h:33).
0x42003caf: is in MDNS::_finishedResolvingName(char*, unsigned char const*) (c:\Users\MarkWest\OneDrive - Sonnys Direct\Documents\Arduino\libraries\ArduinoMDNS\MDNS.cpp:1429).
0x420048ad: MDNS::run() at c:\Users\MarkWest\OneDrive - Sonnys Direct\Documents\Arduino\libraries\ArduinoMDNS\MDNS.cpp:1071
0x4200197f: loop() at C:\Temp\EdgeBox_ESP_100_ResolvingHostNames\EdgeBox_ESP_100_ResolvingHostNames.ino:91
0x42006845: loopTask(void*) at C:\Users\MarkWest\AppData\Local\Arduino15\packages\esp32\hardware\esp32\2.0.14\cores\esp32\main.cpp:50
Paste exception to decode…
Hi there,
Can you try changing the host name to “mark” I don’t think it likes the “-”'s
HTH
GL 
PJ
@PJ_Glasso I removed the dashes from my hostname. Still getting the Guru Mediation Error. However, the system reboots, which it didn’t do before. Here is my serial output.
ETH: Local IP is 192.168.0.66
Enter a mDNS host name via the Arduino Serial Monitor to have it resolved.
Do not postfix the name with “.local”
Resolving 'markdevpi
’ via Multicast DNS (Bonjour)…
Guru Meditation Error: Core 1 panic’ed (LoadProhibited). Exception was unhandled.
Core 1 register dump:
PC : 0x42004f34 PS : 0x00060830 A0 : 0x82003cb2 A1 : 0x3fcebbf0
A2 : 0x3fcebc18 A3 : 0x00000000 A4 : 0x3fc951fc A5 : 0x00000000
A6 : 0x3fcec3b4 A7 : 0x00000000 A8 : 0x3c0302ec A9 : 0x0000002e
A10 : 0x3fcecaa9 A11 : 0x3fcecab0 A12 : 0x000000ff A13 : 0x0000ff00
A14 : 0x00ff0000 A15 : 0xff000000 SAR : 0x00000016 EXCCAUSE: 0x0000001c
EXCVADDR: 0x00000000 LBEG : 0x400556d5 LEND : 0x400556e5 LCOUNT : 0xfffffffb
Backtrace: 0x42004f31:0x3fcebbf0 0x42003caf:0x3fcebc10 0x420048ad:0x3fcebc40 0x4200197f:0x3fcebc80 0x42006845:0x3fcebeb0
ELF file SHA256: 33e69648250ed1e2
Rebooting…
�R~��gBETH: Local IP is 192.168.0.66
Enter a mDNS host name via the Arduino Serial Monitor to have it resolved.
Do not postfix the name with “.local”
Regards, Mark
Hi there,
Ok , you’re getting closer , time to see the code your sending.
Post it using the </> tags above.
I suspect a Lib is the issue.
HTH
GL PJ 
@PJ_Glasso Here you go. Thanks.
#include <SPI.h>
#include <Ethernet.h>
#include <EthernetUdp.h>
#include <ArduinoMDNS.h>
EthernetUDP udp;
MDNS mdns(udp);
void nameFound(const char* name, IPAddress ip);
void setup() {
uint8_t mac[6];
esp_read_mac(mac, ESP_MAC_WIFI_STA);
Ethernet.begin(mac);
// Initialize the mDNS library. You can now reach or ping this
// Arduino via the host name "arduino.local", provided that your operating
// system is mDNS/Bonjour-enabled (such as macOS).
// Always call this before any other method!
mdns.begin(Ethernet.localIP(), "arduino");
// We specify the function that the mDNS library will call when it
// resolves a host name. In this case, we will call the function named
// "nameFound".
mdns.setNameResolvedCallback(nameFound);
Serial.begin(9600);
Serial.print("ETH: Local IP is ");
Serial.println(Ethernet.localIP());
Serial.println("Enter a mDNS host name via the Arduino Serial Monitor to "
"have it resolved.");
Serial.println("Do not postfix the name with \".local\"");
}
void loop() {
char hostName[512];
int length = 0;
// read in a host name from the Arduino IDE's Serial Monitor.
while (Serial.available()) {
hostName[length] = Serial.read();
length = (length + 1) % 512;
delay(5);
}
hostName[length] = '\0';
// You can use the "isResolvingName()" function to find out whether the
// mDNS library is currently resolving a host name.
// If so, we skip this input, since we want our previous request to continue.
if (!mdns.isResolvingName()) {
if (length > 0) {
Serial.print("Resolving '");
Serial.print(hostName);
Serial.println("' via Multicast DNS (Bonjour)...");
// Now we tell the mDNS library to resolve the host name. We give it a
// timeout of 5 seconds (e.g. 5000 milliseconds) to find an answer. The
// library will automatically resend the query every second until it
// either receives an answer or your timeout is reached - In either case,
// the callback function you specified in setup() will be called.
mdns.resolveName(hostName, 5000);
}
}
// This actually runs the mDNS module. YOU HAVE TO CALL THIS PERIODICALLY,
// OR NOTHING WILL WORK! Preferably, call it once per loop().
mdns.run();
}
// This function is called when a name is resolved via mDNS/Bonjour. We set
// this up in the setup() function above. The name you give to this callback
// function does not matter at all, but it must take exactly these arguments
// (a const char*, which is the hostName you wanted resolved, and a const
// byte[4], which contains the IP address of the host on success, or NULL if
// the name resolution timed out).
void nameFound(const char* name, IPAddress ip) {
if (ip != INADDR_NONE) {
Serial.print("The IP address for '");
Serial.print(name);
Serial.print("' is ");
Serial.println(ip);
} else {
Serial.print("Resolving '");
Serial.print(name);
Serial.println("' timed out.");
}
}
Hi there,
AT first Glance, Can you comment this out or move it to the setup, You are running out of memory fast, with buffers that size, try smaller too.
HTH
GL PJ
@PJ_Glasso That worked! I hard-coded the hostname to that of my pi.
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