Added the relevent parts of the .config directory. Alss add ssh config

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diff --git a/vimwiki/Blocked IP Addresses.md b/vimwiki/Blocked IP Addresses.md
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+An application called `fail2ban` blocks IP addresses with repeated failed login attempts. 
+If a user is locked out of ssh connections, this is usually why. 
+
+If you suspect this has happened to someone, you need to know which cluster address they are trying to 
+log in to and ideally what IP address they are coming in from. Each machine that runs an ssh server 
+has its own fail2ban list. 
+
+As root on the machine that the user is trying to log in to, do 
+
+`fail2ban-client set sshd unbanip IPADDRESS` 
+
+Note that normal users log in to both headnode1 and headnode2, so the problem may show up on one or 
+both of these machines. It can’t hurt to unban an IP that is not banned, so you can just do e.g. 
+
+`sudo pdsh –w ‘headnode[1-2]’ fail2ban-client set sshd unbanip IPADDRESS` 
+
+which will unban the IP on both head nodes2. If you have a problem working out the IP that’s banned, 
+try looking at `/var/log/secure.log` on the login machine. 
+