diff --git a/seichi-onp-k8s/manifests/seichi-kubernetes/apps/cluster-wide-apps/app-of-other-apps/argo-workflows-reverse-proxy.yaml b/seichi-onp-k8s/manifests/seichi-kubernetes/apps/cluster-wide-apps/app-of-other-apps/argo-workflows-reverse-proxy.yaml
index a1596048c..e52f4ec9f 100644
--- a/seichi-onp-k8s/manifests/seichi-kubernetes/apps/cluster-wide-apps/app-of-other-apps/argo-workflows-reverse-proxy.yaml
+++ b/seichi-onp-k8s/manifests/seichi-kubernetes/apps/cluster-wide-apps/app-of-other-apps/argo-workflows-reverse-proxy.yaml
@@ -34,6 +34,8 @@ metadata:
   namespace: argocd
 data:
   proxy.conf: |
+    server_names_hash_bucket_size 128;
+
     server {
       listen 80;
       server_name argo-workflows-webhook.onp-k8s.admin.seichi.click;