diff --git a/puppetserver/docker-entrypoint.d/88-enable-cache-delete-api.sh b/puppetserver/docker-entrypoint.d/88-enable-cache-delete-api.sh
index 4dad2a35..a1f36bb0 100644
--- a/puppetserver/docker-entrypoint.d/88-enable-cache-delete-api.sh
+++ b/puppetserver/docker-entrypoint.d/88-enable-cache-delete-api.sh
@@ -1,7 +1,7 @@
 #!/bin/bash
 #
 if [[ "$PUPPETSERVER_ENABLE_ENV_CACHE_DEL_API" == true ]]; then
-  if [ $(grep 'puppet-admin-api' /etc/puppetlabs/puppetserver/conf.d/auth.conf) ]; then
+  if [[ $(grep 'puppet-admin-api' /etc/puppetlabs/puppetserver/conf.d/auth.conf) ]]; then
     echo "Admin API already set"
   else
     /opt/puppetlabs/puppet/bin/ruby /add_cache_del_api_auth_rules.rb