diff --git a/dockerbuild/Dockerfile.centos6 b/dockerbuild/Dockerfile.centos6
deleted file mode 100644
index 6b8f023ed..000000000
--- a/dockerbuild/Dockerfile.centos6
+++ /dev/null
@@ -1,20 +0,0 @@
-FROM centos:6
-
-ARG go_pkg_url
-
-RUN yum update -y
-RUN yum install -y curl git wget openssh-server sudo make rpmdevtools && yum clean all
-
-RUN curl -s $go_pkg_url -o go.tar.gz && \
-    tar -C /usr/local -xzf go.tar.gz && \
-   rm go.tar.gz
-
-RUN groupadd -g 1000 jenkins-build && useradd -u 1000 -g 1000 jenkins-build
-
-RUN echo $'\n\
-  export PATH=$PATH:/usr/local/go/bin:$HOME/go/bin\n'\
-  >> ~/.bash_profile
-
-RUN mkdir /rpmbuild && chmod 777 /rpmbuild
-
-CMD ["/usr/sbin/sshd", "-D"]
diff --git a/dockerbuild/Dockerfile.centos6-i386 b/dockerbuild/Dockerfile.centos6-i386
deleted file mode 100644
index c6a47072b..000000000
--- a/dockerbuild/Dockerfile.centos6-i386
+++ /dev/null
@@ -1,21 +0,0 @@
-FROM i386/centos:6
-
-ARG go_pkg_url
-
-RUN echo i386 > /etc/yum/vars/basearch && echo i686 > /etc/yum/vars/arch
-
-RUN yum install -y curl git wget openssh-server sudo make rpmdevtools && yum clean all
-
-RUN curl -s $go_pkg_url -o go.tar.gz && \
-    tar -C /usr/local -xzf go.tar.gz && \
-    rm go.tar.gz
-
-RUN groupadd -g 1000 jenkins-build && useradd -u 1000 -g 1000 jenkins-build
-
-RUN echo $'\n\
-  export PATH=$PATH:/usr/local/go/bin:$HOME/go/bin\n'\
-  >> ~/.bash_profile
-
-RUN mkdir /rpmbuild && chmod 777 /rpmbuild
-
-CMD ["/usr/sbin/sshd", "-D"]
diff --git a/dockerbuild/Dockerfile.centos7-i386 b/dockerbuild/Dockerfile.centos7-i386
index f7ee9a0c4..4d0a28023 100644
--- a/dockerbuild/Dockerfile.centos7-i386
+++ b/dockerbuild/Dockerfile.centos7-i386
@@ -2,8 +2,11 @@ FROM centos:7
 
 ARG go_pkg_url
 
-RUN yum install -y curl git wget openssh-server sudo make development-tools rpmdevtools clang gcc-c++ ruby ruby-devel && yum clean all
-
+RUN yum install -y curl git wget openssh-server sudo make development-tools rpmdevtools clang gcc-c++ ruby ruby-devel ssl-devel && yum clean all
+RUN curl -s -k -L https://github.com/Kitware/CMake/releases/download/v3.17.3/cmake-3.17.3.tar.gz -o cmake-3.17.3.tar.gz && tar -xzf cmake-3.17.3.tar.gz
+WORKDIR /cmake-3.17.3
+RUN ./bootstrap && make -j8 && make install
+WORKDIR /
 RUN curl -s $go_pkg_url -o go.tar.gz && \
     tar -C /usr/local -xzf go.tar.gz && \
     rm go.tar.gz
diff --git a/dockerbuild/Makefile b/dockerbuild/Makefile
index cb54f9bc6..596f271c5 100644
--- a/dockerbuild/Makefile
+++ b/dockerbuild/Makefile
@@ -16,8 +16,6 @@ alpine:
 centos:
 	@docker buildx build --build-arg go_pkg_url="https://dl.google.com/go/go${GO_VERSION}.linux-amd64.tar.gz" --platform linux/amd64 -f Dockerfile.centos7 . -t ztbuild/centos7-amd64 --load
 	@docker buildx build --build-arg go_pkg_url="https://dl.google.com/go/go${GO_VERSION}.linux-386.tar.gz" --platform linux/386 -f Dockerfile.centos7-i386 . -t ztbuild/centos7-i386 --load
-	@docker buildx build --build-arg go_pkg_url="https://dl.google.com/go/go${GO_VERSION}.linux-amd64.tar.gz" --platform linux/amd64 -f Dockerfile.centos6 . -t ztbuild/centos6-amd64 --load
-	@docker buildx build --build-arg go_pkg_url="https://dl.google.com/go/go${GO_VERSION}.linux-386.tar.gz" --platform linux/386 -f Dockerfile.centos6-i386 . -t ztbuild/centos6-i386 --load
 	@docker buildx build --build-arg go_pkg_url="https://dl.google.com/go/go${GO_VERSION}.linux-amd64.tar.gz" --platform linux/amd64 -f Dockerfile.centos8 . -t ztbuild/centos8-amd64 --load
 	@docker buildx build --build-arg go_pkg_url="https://dl.google.com/go/go${GO_VERSION}.linux-arm64.tar.gz" --platform linux/arm64 -f Dockerfile.centos8 . -t ztbuild/centos8-arm64 --load
 	@docker buildx build --build-arg go_pkg_url="https://dl.google.com/go/go${GO_VERSION}.linux-ppc64le.tar.gz" --platform linux/ppc64le -f Dockerfile.centos8 . -t ztbuild/centos8-ppc64le --load