Index: postlfs/security/firewalling.xml
===================================================================
--- postlfs/security/firewalling.xml	(revision 2c871871fb5ce59b5eec21da0a4cb315c3d882dd)
+++ postlfs/security/firewalling.xml	(revision cd29bc9b3d06f82ca64ab123ed167e277d7f0dd7)
@@ -212,22 +212,33 @@
       <blockquote>
         <literallayout>
-<ulink url="http://www.netfilter.org/">www.netfilter.org - Homepage of the netfilter/iptables/nftables projects</ulink>
-<ulink url="http://www.netfilter.org/documentation/FAQ/netfilter-faq.html">Netfilter related FAQ</ulink>
-<ulink url="http://www.netfilter.org/documentation/index.html#HOWTO">Netfilter related HOWTO's</ulink>
+<ulink url="https://www.netfilter.org/">www.netfilter.org - Homepage of the netfilter/iptables/nftables projects</ulink>
+<ulink url="https://www.netfilter.org/documentation/FAQ/netfilter-faq.html">Netfilter related FAQ</ulink>
+<ulink url="https://www.netfilter.org/documentation/index.html#HOWTO">Netfilter related HOWTO's</ulink>
 <ulink url="https://wiki.nftables.org/wiki-nftables/index.php/Main_Page">nftables HOWTO</ulink>
-<ulink url="http://en.tldp.org/LDP/nag2/x-087-2-firewall.html">en.tldp.org/LDP/nag2/x-087-2-firewall.html</ulink>
-<ulink url="http://en.tldp.org/HOWTO/Security-HOWTO.html">en.tldp.org/HOWTO/Security-HOWTO.html</ulink>
-<ulink url="http://en.tldp.org/HOWTO/Firewall-HOWTO.html">en.tldp.org/HOWTO/Firewall-HOWTO.html</ulink>
-<ulink url="http://www.linuxsecurity.com/docs/">www.linuxsecurity.com/docs/</ulink>
-<ulink url="http://www.little-idiot.de/firewall">www.little-idiot.de/firewall (German &amp; outdated, but very comprehensive)</ulink>
+<ulink url="https://tldp.org/LDP/nag2/x-087-2-firewall.html">tldp.org/LDP/nag2/x-087-2-firewall.html</ulink>
+<ulink url="https://tldp.org/HOWTO/Security-HOWTO.html">tldp.org/HOWTO/Security-HOWTO.html</ulink>
+<ulink url="https://tldp.org/HOWTO/Firewall-HOWTO.html">tldp.org/HOWTO/Firewall-HOWTO.html</ulink>
+<ulink url="https://linuxsecurity.com/howtos">linuxsecurity.com/howtos</ulink>
+<ulink url="http://www.e-infomax.com/ipmasq">www.e-infomax.com/ipmasq</ulink>
+<ulink url="https://www.circlemud.org/jelson/writings/security/index.htm">www.circlemud.org/jelson/writings/security/index.htm</ulink>
+<ulink url="https://insecure.org/reading.html">insecure.org/reading.html</ulink>
+        </literallayout>
+
+<!-- comment-out entries moved out of literallayout to avoid empty lines -->
+
+<!-- not accssible 2022-09-08
+<ulink url="http://www.little-idiot.de/firewall">www.little-idiot.de/firewall (German &amp; outdated, but very comprehensive)</ulink>-->
+<!-- redirects somewhere you can buy a book, not sure if we should link to
+     a book which you'll need to pay for reading
 <ulink url="http://linux.oreillynet.com/pub/a/linux/2000/03/10/netadmin/ddos.html">linux.oreillynet.com/pub/a/linux/2000/03/10/netadmin/ddos.html</ulink>
-<ulink url="http://staff.washington.edu/dittrich/misc/ddos">staff.washington.edu/dittrich/misc/ddos</ulink>
-<ulink url="http://www.e-infomax.com/ipmasq">www.e-infomax.com/ipmasq</ulink>
-<ulink url="http://www.circlemud.org/~jelson/writings/security/index.htm">www.circlemud.org/~jelson/writings/security/index.htm</ulink>
-<ulink url="http://www.securityfocus.com">www.securityfocus.com</ulink>
-<ulink url="http://www.cert.org/tech_tips/">www.cert.org - tech_tips</ulink>
-<ulink url="http://security.ittoolbox.com/">security.ittoolbox.com</ulink>
-<ulink url="http://www.insecure.org/reading.html">www.insecure.org/reading.html</ulink>
-        </literallayout>
+-->
+<!-- 404 2022-09-08
+<ulink url="http://staff.washington.edu/dittrich/misc/ddos">staff.washington.edu/dittrich/misc/ddos</ulink> -->
+<!-- redirects to dead bugtraq
+<ulink url="http://www.securityfocus.com">www.securityfocus.com</ulink>-->
+<!-- redirects to CERT main page
+<ulink url="http://www.cert.org/tech_tips/">www.cert.org - tech_tips</ulink>-->
+<!-- not accessible 2022-09-08
+<ulink url="http://security.ittoolbox.com/">security.ittoolbox.com</ulink> -->
       </blockquote>
 
