diff --git a/nginx_stage/lib/nginx_stage/user.rb b/nginx_stage/lib/nginx_stage/user.rb
index f018d8b343..0bef299f6d 100644
--- a/nginx_stage/lib/nginx_stage/user.rb
+++ b/nginx_stage/lib/nginx_stage/user.rb
@@ -36,6 +36,18 @@ def initialize(user)
       @passwd = Etc.getpwnam user.to_s
       @group = Etc.getgrgid gid
       @groups = get_groups
+
+      if name.to_s != user.to_s
+        err_msg = <<~HEREDOC
+          Username '#{user}' is being mapped to '#{name}' in SSSD and they don't match.
+          Users with domain names cannot be mapped correctly. If '#{name}' still has the
+          domain in it you'll need to set SSSD's full_name_format to '%1$s'.
+
+          See https://github.com/OSC/ondemand/issues/1759 for more details.
+        HEREDOC
+
+        raise StandardError, err_msg
+      end
     end
 
     # User's primary group name
diff --git a/nginx_stage/spec/user_spec.rb b/nginx_stage/spec/user_spec.rb
new file mode 100644
index 0000000000..a71463ebbf
--- /dev/null
+++ b/nginx_stage/spec/user_spec.rb
@@ -0,0 +1,43 @@
+require 'nginx_stage'
+require 'spec_helper'
+
+describe NginxStage::User do
+
+  let(:test_user) { "spec" }
+  let(:test_user_full_name) { "spec@domain.edu" }
+  let(:test_user_gid) { 1111 }
+
+  def stub_etc(username)
+    etc_stub = {
+      :gid => test_user_gid,
+      :name => username
+    }
+
+    allow(Etc).to receive(:getpwnam).with(test_user).and_return(Struct.new(*etc_stub.keys).new(*etc_stub.values))
+    allow(Etc).to receive(:getgrgid).with(test_user_gid).and_return(nil)
+    allow_any_instance_of(NginxStage::User).to receive(:get_groups).and_return([test_user])
+  end
+
+  describe 'initialization' do
+
+    it 'initializes correctly' do
+      stub_etc(test_user)
+
+      u = described_class.new(test_user)
+      expect(u.name).to equal(test_user)
+    end
+
+    it 'raises an error when etc is different from username' do
+      stub_etc(test_user_full_name)
+
+      msg = <<~HEREDOC
+        Username 'spec' is being mapped to 'spec@domain.edu' in SSSD and they don't match.
+        Users with domain names cannot be mapped correctly. If 'spec@domain.edu' still has the
+        domain in it you'll need to set SSSD's full_name_format to '%1$s'.
+      
+        See https://github.com/OSC/ondemand/issues/1759 for more details.
+      HEREDOC
+      expect { described_class.new(test_user) }.to raise_error(StandardError, msg)
+    end
+  end
+end
\ No newline at end of file