this is just to make the text convey to us that the fix should happen on
alberti. there's no need to use cumin on all hosts for this

howto/upgrades.md

@@ -393,11 +393,14 @@ Sometimes, userdir-ldap's `ud-replicate` leaves a multiplexing SSH
 process lying around and those show up as part of
 `cron.service`.
 
-Logging into the LDAP server (currently `alberti`) and killing all the
-`sshdist` process will clear those:
+We can close all of those connections up at once, on one host, by logging into
+the LDAP server (currently `alberti`) and killing all the ssh processes running
+under the `sshdist` user:
 
     pkill -u sshdist ssh
 
+That should clear out all processes on other hosts.
+
 ## systemd user manager services
 
 The `needrestart` tool [lacks](https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=843778)