I connect my laptop to a server in the same room using wifi.
I use ssh and sshfs to do so.
Laptop runs chimaera; server runs beowulf.

I use ssh to communicate with mutt and with gnucash on the server.
I use sshfs to access the server's file system.

For the last few days, I've been getting disconnections using ssh,
with the message
    client_loop: send disconnect: Broken pipe

It's obvious that the wifi connection ha gone down, except
* ping tells me it' still up
* my sshfs connection I have is still up.
* connection to the rest of the world (via the same wifi) is still up.

Any ideas?