Change the linux for linux artifacts to CentOS 6

tools/dockerfile/grpc_artifact_centos6_x64/Dockerfile

@@ -0,0 +1,58 @@
+# Copyright 2016 gRPC authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# Docker file for building gRPC artifacts.
+
+##################
+# Base
+
+FROM dockcross/manylinux2010-x64
+
+# Install essential packages.
+RUN yum -y install golang strace
+
+
+##################
+# Ruby dependencies
+
+# Install rvm
+RUN gpg --keyserver hkp://pool.sks-keyservers.net --recv-keys 409B6B1796C275462A1703113804BB82D39DC0E3 7D2BAF1CF37B13E2069D6956105BD0E739499BDB
+RUN \curl -sSL https://get.rvm.io | bash -s stable
+
+# Install Ruby 2.6
+RUN /bin/bash -l -c "rvm install ruby-2.6"
+RUN /bin/bash -l -c "rvm use --default ruby-2.6"
+RUN /bin/bash -l -c "echo 'gem: --no-document' > ~/.gemrc"
+RUN /bin/bash -l -c "echo 'export PATH=/usr/local/rvm/bin:$PATH' >> ~/.bashrc"
+RUN /bin/bash -l -c "echo 'rvm --default use ruby-2.6' >> ~/.bashrc"
+RUN /bin/bash -l -c "gem install bundler"
+
+
+##################
+# PHP dependencies
+
+RUN yum -y install php5 php5-dev php-pear
+
+RUN wget https://phar.phpunit.de/phpunit-5.7.27.phar && \
+  mv phpunit-5.7.27.phar /usr/local/bin/phpunit && \
+  chmod +x /usr/local/bin/phpunit
+
+# Clean yum
+RUN yum clean all
+
+# Create default work directory.
+RUN mkdir /var/local/jenkins
+
+# Define the default command.
+CMD ["bash"]

tools/dockerfile/grpc_artifact_centos6_x86/Dockerfile

@@ -0,0 +1,58 @@
+# Copyright 2016 gRPC authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# Docker file for building gRPC artifacts.
+
+##################
+# Base
+
+FROM dockcross/manylinux2010-x86
+
+# Install essential packages.
+RUN yum -y install golang strace
+
+
+##################
+# Ruby dependencies
+
+# Install rvm
+RUN gpg --keyserver hkp://pool.sks-keyservers.net --recv-keys 409B6B1796C275462A1703113804BB82D39DC0E3 7D2BAF1CF37B13E2069D6956105BD0E739499BDB
+RUN \curl -sSL https://get.rvm.io | bash -s stable
+
+# Install Ruby 2.6
+RUN /bin/bash -l -c "rvm install ruby-2.6"
+RUN /bin/bash -l -c "rvm use --default ruby-2.6"
+RUN /bin/bash -l -c "echo 'gem: --no-document' > ~/.gemrc"
+RUN /bin/bash -l -c "echo 'export PATH=/usr/local/rvm/bin:$PATH' >> ~/.bashrc"
+RUN /bin/bash -l -c "echo 'rvm --default use ruby-2.6' >> ~/.bashrc"
+RUN /bin/bash -l -c "gem install bundler"
+
+
+##################
+# PHP dependencies
+
+RUN yum -y install php5 php5-dev php-pear
+
+RUN wget https://phar.phpunit.de/phpunit-5.7.27.phar && \
+  mv phpunit-5.7.27.phar /usr/local/bin/phpunit && \
+  chmod +x /usr/local/bin/phpunit
+
+# Clean yum
+RUN yum clean all
+
+# Create default work directory.
+RUN mkdir /var/local/jenkins
+
+# Define the default command.
+CMD ["bash"]

tools/run_tests/artifacts/artifact_targets.py

@@ -271,7 +271,7 @@ class CSharpExtArtifact:
                     cmake_arch_option = '-DOPENSSL_NO_ASM=ON'
                 return create_docker_jobspec(
                     self.name,
-                    'tools/dockerfile/grpc_artifact_linux_%s' % self.arch,
+                    'tools/dockerfile/grpc_artifact_centos6_%s' % self.arch,
                     'tools/run_tests/artifacts/build_artifact_csharp.sh',
                     environ={
                         'CMAKE_ARCH_OPTION': cmake_arch_option
@@ -304,7 +304,7 @@ class PHPArtifact:
 
     def build_jobspec(self):
         return create_docker_jobspec(
-            self.name, 'tools/dockerfile/grpc_artifact_linux_{}'.format(
+            self.name, 'tools/dockerfile/grpc_artifact_centos6_{}'.format(
                 self.arch), 'tools/run_tests/artifacts/build_artifact_php.sh')