diff --git a/nodepool/scripts/configure_mirror.sh b/nodepool/scripts/configure_mirror.sh
index 0059009081..a4db82e7c0 100755
--- a/nodepool/scripts/configure_mirror.sh
+++ b/nodepool/scripts/configure_mirror.sh
@@ -19,6 +19,7 @@
 source /etc/nodepool/provider
 
 NODEPOOL_MIRROR_HOST=${NODEPOOL_MIRROR_HOST:-mirror.$NODEPOOL_REGION.$NODEPOOL_CLOUD.openstack.org}
+NODEPOOL_MIRROR_HOST=$(echo $NODEPOOL_MIRROR_HOST|tr '[:upper:]' '[:lower:]')
 NODEPOOL_PYPI_MIRROR=${NODEPOOL_PYPI_MIRROR:-http://$NODEPOOL_MIRROR_HOST/pypi/simple}
 
 cat >/tmp/pip.conf <<EOF