diff --git a/README b/README
index edbbbbcc..47089579 100644
--- a/README
+++ b/README
@@ -1,40 +1,46 @@
 #
 # Copyright (C) 2010-2020 Red Hat, Inc.  All rights reserved.
 #
 # Author: Fabio M. Di Nitto <fabbione@kronosnet.org>
 #
 # This software licensed under GPL-2.0+
 #
 
 Upstream resources
 ------------------
 
 https://github.com/kronosnet/kronosnet/
 https://ci.kronosnet.org/
 https://trello.com/kronosnet (TODO list and activities tracking)
 https://goo.gl/9ZvkLS (google shared drive)
 https://github.com/kronosnet/knet-ansible-ci
 https://lists.kronosnet.org/mailman/listinfo/users
 https://lists.kronosnet.org/mailman/listinfo/devel
 https://lists.kronosnet.org/mailman/listinfo/commits
 https://kronosnet.org/ (web 0.1 style)
 IRC: #kronosnet on Freenode
 
 Architecture
 ------------
 
 Please refer to the google shared drive Presentations directory for
 diagrams and fancy schemas
 
 Running knet on FreeBSD
 -----------------------
 
 knet requires big socket buffers and you need to set:
 kern.ipc.maxsockbuf=18388608
 in /etc/sysctl.conf or knet will fail to run.
 
-currently, knet requires also:
+For version 12 (or lower), knet requires also:
 net.inet.sctp.blackhole=1
 in /etc/sysctl.conf or knet will fail to work with SCTP.
+This sysctl is obsoleted in version 13.
 
 libnozzle requires if_tap.ko loaded in the kernel.
+
+Please avoid to use ifconfig_DEFAULT in /etc/rc.conf to use
+DHCP for all interfaces or the dhclient will interfere with
+libnozzle interface management, causing errors on some
+operations such as "ifconfig tap down".