There are a couple of instructions out there to reset a salt minion. For me, these don't seem to work reliably and the salt minion is not able to re-register to a new master (or report back).
So here are the steps that I take:
rm -f /etc/salt/pki/minion/minion.pem
rm -f /etc/salt/pki/minion/minion.pub
cat /dev/null > /etc/salt/minion_id
rm -f /etc/salt/pki/minion/minion_master.pub
service salt-minion restart
service salt-minion status
# check if there are errors on service salt-minion status
# Delete the key on the salt master
service salt-minion restart
Maybe these commands also help on the master:
salt-key -L # lists all client keys
saltkey -A # Accept client keys