diff --git a/templates/ssh_config.erb b/templates/ssh_config.erb
index 8cf7db3..5546a10 100644
--- a/templates/ssh_config.erb
+++ b/templates/ssh_config.erb
@@ -1,60 +1,60 @@
 # File managed by Puppet
 <%-
   def bool2str(v)
     case v
     when true
       'yes'
     when false
       'no'
     else
       v
     end
   end
 -%>
 
 <%- @options.each do |k, v| -%>
 <%- if v.is_a?(Hash) -%>
 <%- if k.length > 1024 -%>
 <%- fail("Line exceeds 1024 characters: #{k}") -%>
 <%- end -%>
 <%= k %>
 <%- v.sort.each do |key, value| -%>
     <%- if value.is_a?(Array) -%>
     <%- value.each do |a| -%>
-    <%- if a != '' -%>
+    <%- if a != '' && a != nil -%>
     <%- line_content = "#{key} #{bool2str(a)}" -%>
     <%- if line_content.length > 1020 -%>
     <%- fail("Line exceeds 1024 characters: #{line_content}") -%>
     <%- else -%>
     <%= line_content %>
     <%- end -%>
     <%- end -%>
     <%- end -%>
-    <%- elsif value != '' -%>
+    <%- elsif value != '' && value != nil -%>
     <%- line_content = "#{key} #{bool2str(value)}" -%>
     <%- if line_content.length > 1020 -%>
     <%- fail("Line exceeds 1024 characters: #{line_content}") -%>
     <%- end -%>
     <%= line_content %>
     <%- end -%>
 <%- end -%>
 <%- else -%>
 <%- if v.is_a?(Array) -%>
 <%- v.each do |a| -%>
-<%- if a != '' -%>
+<%- if a != '' && a != nil -%>
 <%- line_content = "#{k} #{bool2str(a)}" -%>
 <%- if line_content.length > 1024 -%>
 <%- fail("Line exceeds 1024 characters: #{line_content}") -%>
 <%- end -%>
 <%= k %> <%= bool2str(a) %>
 <%- end -%>
 <%- end -%>
-<%- elsif v != :undef and v != '' -%>
+<%- elsif v != :undef && v != '' && v != nil -%>
 <%- line_content = "#{k} #{bool2str(v)}" -%>
 <%- if line_content.length > 1024 -%>
 <%- fail("Line exceeds 1024 characters: #{line_content}") -%>
 <%- end -%>
 <%= k %> <%= bool2str(v) %>
 <%- end -%>
 <%- end -%>
 <%- end -%>