diff --git a/runner/Dockerfile b/runner/Dockerfile
index f9b73dbe0d..66887c641a 100644
--- a/runner/Dockerfile
+++ b/runner/Dockerfile
@@ -47,8 +47,8 @@ RUN apt update -y \
 # arch command on OS X reports "i386" for Intel CPUs regardless of bitness
 RUN export ARCH=$(echo ${TARGETPLATFORM} | cut -d / -f2) \
     && if [ "$ARCH" = "arm64" ]; then export ARCH=aarch64 ; fi \
-    && if [ "$ARCH" = "i386" ]; then export ARCH=x86_64 ; fi \
-    && curl -L -o /usr/local/bin/dumb-init https://github.com/Yelp/dumb-init/releases/download/v${DUMB_INIT_VERSION}/dumb-init_${DUMB_INIT_VERSION}_${ARCH} \
+    && if [ "$ARCH" = "amd64" ] || [ "$ARCH" = "i386" ]; then export ARCH=x86_64 ; fi \
+    && curl -f -L -o /usr/local/bin/dumb-init https://github.com/Yelp/dumb-init/releases/download/v${DUMB_INIT_VERSION}/dumb-init_${DUMB_INIT_VERSION}_${ARCH} \
     && chmod +x /usr/local/bin/dumb-init
 
 # Docker download supports arm64 as aarch64 & amd64 / i386 as x86_64
diff --git a/runner/Dockerfile.dindrunner b/runner/Dockerfile.dindrunner
index aedc1cb7a2..6284cb11cf 100644
--- a/runner/Dockerfile.dindrunner
+++ b/runner/Dockerfile.dindrunner
@@ -108,8 +108,8 @@ RUN chmod +x /usr/local/bin/startup.sh /usr/local/bin/entrypoint.sh /usr/local/b
 # arch command on OS X reports "i386" for Intel CPUs regardless of bitness
 RUN export ARCH=$(echo ${TARGETPLATFORM} | cut -d / -f2) \
     && if [ "$ARCH" = "arm64" ]; then export ARCH=aarch64 ; fi \
-    && if [ "$ARCH" = "i386" ]; then export ARCH=x86_64 ; fi \
-    && curl -L -o /usr/local/bin/dumb-init https://github.com/Yelp/dumb-init/releases/download/v${DUMB_INIT_VERSION}/dumb-init_${DUMB_INIT_VERSION}_${ARCH} \
+    && if [ "$ARCH" = "amd64" ] || [ "$ARCH" = "i386" ]; then export ARCH=x86_64 ; fi \
+    && curl -f -L -o /usr/local/bin/dumb-init https://github.com/Yelp/dumb-init/releases/download/v${DUMB_INIT_VERSION}/dumb-init_${DUMB_INIT_VERSION}_${ARCH} \
     && chmod +x /usr/local/bin/dumb-init
 
 VOLUME /var/lib/docker
diff --git a/runner/Dockerfile.ubuntu.1804 b/runner/Dockerfile.ubuntu.1804
index 93ae67ecd7..3bc396ea2c 100644
--- a/runner/Dockerfile.ubuntu.1804
+++ b/runner/Dockerfile.ubuntu.1804
@@ -47,8 +47,8 @@ RUN apt update -y \
 # arch command on OS X reports "i386" for Intel CPUs regardless of bitness
 RUN export ARCH=$(echo ${TARGETPLATFORM} | cut -d / -f2) \
     && if [ "$ARCH" = "arm64" ]; then export ARCH=aarch64 ; fi \
-    && if [ "$ARCH" = "i386" ]; then export ARCH=x86_64 ; fi \
-    && curl -L -o /usr/local/bin/dumb-init https://github.com/Yelp/dumb-init/releases/download/v${DUMB_INIT_VERSION}/dumb-init_${DUMB_INIT_VERSION}_${ARCH} \
+    && if [ "$ARCH" = "amd64" ] || [ "$ARCH" = "i386" ]; then export ARCH=x86_64 ; fi \
+    && curl -f -L -o /usr/local/bin/dumb-init https://github.com/Yelp/dumb-init/releases/download/v${DUMB_INIT_VERSION}/dumb-init_${DUMB_INIT_VERSION}_${ARCH} \
     && chmod +x /usr/local/bin/dumb-init
 
 # Docker download supports arm64 as aarch64 & amd64 / i386 as x86_64