ESP32, Embassy & Sockets

Sun, 09 Aug 2026 12:02:50 +0100

The Problem

I was running a webserver (picoserve), but I was only able to run one worker; somewhere in the picoserve code I was running into a panic from SocketSet add function, specifically this panic:

match &mut self.sockets {
 ManagedSlice::Borrowed(_) => panic!("adding a socket to a full SocketSet"),
 #[cfg(feature = "alloc")]
 ManagedSlice::Owned(sockets) => {
 sockets.push(SocketStorage { inner: None });
 let index = sockets.len() - 1;
 put(index, &mut sockets[index], socket)
 }
}

The problem, I eventually figured out, was that the network stack created with embassy-net was being initialized with 3 sockets: one for DHCP, one for DNS, and one for the rest of the code.

Embassy on Notebook

ESP32, Embassy & Sockets

The Problem