Update sites using ServerCredentials.new
diff --git a/src/ruby/bin/math_server.rb b/src/ruby/bin/math_server.rb
index b41ccf6..5e2b7e7 100755
--- a/src/ruby/bin/math_server.rb
+++ b/src/ruby/bin/math_server.rb
@@ -155,7 +155,8 @@
 
 def test_server_creds
   certs = load_test_certs
-  GRPC::Core::ServerCredentials.new(nil, certs[1], certs[2])
+  GRPC::Core::ServerCredentials.new(
+    nil, [{ private_key: certs[1], cert_chain: certs[2] }], false)
 end
 
 def main
diff --git a/src/ruby/bin/noproto_server.rb b/src/ruby/bin/noproto_server.rb
index 90baaf9..72a5762 100755
--- a/src/ruby/bin/noproto_server.rb
+++ b/src/ruby/bin/noproto_server.rb
@@ -77,7 +77,8 @@
 
 def test_server_creds
   certs = load_test_certs
-  GRPC::Core::ServerCredentials.new(nil, certs[1], certs[2])
+  GRPC::Core::ServerCredentials.new(
+    nil, [{ private_key: certs[1], cert_chain: certs[2] }], false)
 end
 
 def main
diff --git a/src/ruby/pb/test/server.rb b/src/ruby/pb/test/server.rb
index e2e1ecb..a311bb7 100755
--- a/src/ruby/pb/test/server.rb
+++ b/src/ruby/pb/test/server.rb
@@ -64,7 +64,8 @@
 # creates a ServerCredentials from the test certificates.
 def test_server_creds
   certs = load_test_certs
-  GRPC::Core::ServerCredentials.new(nil, certs[1], certs[2])
+  GRPC::Core::ServerCredentials.new(
+      nil, [{private_key: certs[1], cert_chain: certs[2]}], false)
 end
 
 # produces a string of null chars (\0) of length l.
diff --git a/src/ruby/spec/client_server_spec.rb b/src/ruby/spec/client_server_spec.rb
index 2e673ff..9aacea9 100644
--- a/src/ruby/spec/client_server_spec.rb
+++ b/src/ruby/spec/client_server_spec.rb
@@ -32,12 +32,6 @@
 
 include GRPC::Core
 
-def load_test_certs
-  test_root = File.join(File.dirname(__FILE__), 'testdata')
-  files = ['ca.pem', 'server1.key', 'server1.pem']
-  files.map { |f| File.open(File.join(test_root, f)).read }
-end
-
 shared_context 'setup: tags' do
   let(:sent_message) { 'sent message' }
   let(:reply_text) { 'the reply' }
@@ -420,12 +414,19 @@
 end
 
 describe 'the secure http client/server' do
+  def load_test_certs
+    test_root = File.join(File.dirname(__FILE__), 'testdata')
+    files = ['ca.pem', 'server1.key', 'server1.pem']
+    files.map { |f| File.open(File.join(test_root, f)).read }
+  end
+
   before(:example) do
     certs = load_test_certs
     server_host = '0.0.0.0:0'
     @client_queue = GRPC::Core::CompletionQueue.new
     @server_queue = GRPC::Core::CompletionQueue.new
-    server_creds = GRPC::Core::ServerCredentials.new(nil, certs[1], certs[2])
+    server_creds = GRPC::Core::ServerCredentials.new(
+      nil, [{ private_key: certs[1], cert_chain: certs[2] }], false)
     @server = GRPC::Core::Server.new(@server_queue, nil)
     server_port = @server.add_http2_port(server_host, server_creds)
     @server.start
diff --git a/src/ruby/spec/credentials_spec.rb b/src/ruby/spec/credentials_spec.rb
index 8e72e85..b02219d 100644
--- a/src/ruby/spec/credentials_spec.rb
+++ b/src/ruby/spec/credentials_spec.rb
@@ -29,15 +29,15 @@
 
 require 'grpc'
 
-def load_test_certs
-  test_root = File.join(File.dirname(__FILE__), 'testdata')
-  files = ['ca.pem', 'server1.pem', 'server1.key']
-  files.map { |f| File.open(File.join(test_root, f)).read }
-end
+describe GRPC::Core::Credentials do
+  Credentials = GRPC::Core::Credentials
 
-Credentials = GRPC::Core::Credentials
+  def load_test_certs
+    test_root = File.join(File.dirname(__FILE__), 'testdata')
+    files = ['ca.pem', 'server1.pem', 'server1.key']
+    files.map { |f| File.open(File.join(test_root, f)).read }
+  end
 
-describe Credentials do
   describe '#new' do
     it 'can be constructed with fake inputs' do
       expect { Credentials.new('root_certs', 'key', 'cert') }.not_to raise_error
diff --git a/src/ruby/spec/server_credentials_spec.rb b/src/ruby/spec/server_credentials_spec.rb
index 55598bc..8ae5770 100644
--- a/src/ruby/spec/server_credentials_spec.rb
+++ b/src/ruby/spec/server_credentials_spec.rb
@@ -31,8 +31,9 @@
 
 def load_test_certs
   test_root = File.join(File.dirname(__FILE__), 'testdata')
-  files = ['ca.pem', 'server1.pem', 'server1.key']
-  files.map { |f| File.open(File.join(test_root, f)).read }
+  files = ['ca.pem', 'server1.key', 'server1.pem']
+  contents = files.map { |f| File.open(File.join(test_root, f)).read }
+  [contents[0], [{ private_key: contents[1], cert_chain: contents[2] }], false]
 end
 
 describe GRPC::Core::ServerCredentials do
@@ -40,7 +41,8 @@
 
   describe '#new' do
     it 'can be constructed from a fake CA PEM, server PEM and a server key' do
-      expect { Creds.new('a', 'b', 'c') }.not_to raise_error
+      creds = Creds.new('a', [{ private_key: 'a', cert_chain: 'b' }], false)
+      expect(creds).to_not be_nil
     end
 
     it 'can be constructed using the test certificates' do
@@ -48,21 +50,44 @@
       expect { Creds.new(*certs) }.not_to raise_error
     end
 
+    it 'cannot be constructed without a nil key_cert pair array' do
+      root_cert, _, _ = load_test_certs
+      blk = proc do
+        Creds.new(root_cert, nil, false)
+      end
+      expect(&blk).to raise_error
+    end
+
+    it 'cannot be constructed without any key_cert pairs' do
+      root_cert, _, _ = load_test_certs
+      blk = proc do
+        Creds.new(root_cert, [], false)
+      end
+      expect(&blk).to raise_error
+    end
+
     it 'cannot be constructed without a server cert chain' do
       root_cert, server_key, _ = load_test_certs
-      blk = proc { Creds.new(root_cert, server_key, nil) }
+      blk = proc do
+        Creds.new(root_cert,
+                  [{ server_key: server_key, cert_chain: nil }],
+                  false)
+      end
       expect(&blk).to raise_error
     end
 
     it 'cannot be constructed without a server key' do
       root_cert, _, _ = load_test_certs
-      blk = proc { Creds.new(root_cert, nil, cert_chain) }
+      blk = proc do
+        Creds.new(root_cert,
+                  [{ server_key: nil, cert_chain: cert_chain }])
+      end
       expect(&blk).to raise_error
     end
 
     it 'can be constructed without a root_cret' do
-      _, server_key, cert_chain = load_test_certs
-      blk = proc { Creds.new(nil, server_key, cert_chain) }
+      _, cert_pairs, _ = load_test_certs
+      blk = proc { Creds.new(nil, cert_pairs, false) }
       expect(&blk).to_not raise_error
     end
   end
diff --git a/src/ruby/spec/server_spec.rb b/src/ruby/spec/server_spec.rb
index 47fe575..c52fe0d 100644
--- a/src/ruby/spec/server_spec.rb
+++ b/src/ruby/spec/server_spec.rb
@@ -32,7 +32,8 @@
 def load_test_certs
   test_root = File.join(File.dirname(__FILE__), 'testdata')
   files = ['ca.pem', 'server1.key', 'server1.pem']
-  files.map { |f| File.open(File.join(test_root, f)).read }
+  contents = files.map { |f| File.open(File.join(test_root, f)).read }
+  [contents[0], [{ private_key: contents[1], cert_chain: contents[2] }], false]
 end
 
 Server = GRPC::Core::Server