diff --git a/modules/ngx_http_upstream_dyups_module/ngx_http_dyups.h b/modules/ngx_http_upstream_dyups_module/ngx_http_dyups.h
index 54923e38ed..58350eb57f 100644
--- a/modules/ngx_http_upstream_dyups_module/ngx_http_dyups.h
+++ b/modules/ngx_http_upstream_dyups_module/ngx_http_dyups.h
@@ -27,4 +27,6 @@ extern ngx_flag_t ngx_http_dyups_api_enable;
 extern ngx_dyups_add_upstream_filter_pt ngx_dyups_add_upstream_top_filter;
 extern ngx_dyups_del_upstream_filter_pt ngx_dyups_del_upstream_top_filter;
 
+extern void ngx_http_upstream_keepalive_clear_cache_connections(ngx_http_upstream_srv_conf_t *us);
+
 #endif
diff --git a/modules/ngx_http_upstream_dyups_module/ngx_http_dyups_module.c b/modules/ngx_http_upstream_dyups_module/ngx_http_dyups_module.c
index 8135ad4336..fb24c0df16 100644
--- a/modules/ngx_http_upstream_dyups_module/ngx_http_dyups_module.c
+++ b/modules/ngx_http_upstream_dyups_module/ngx_http_dyups_module.c
@@ -1717,6 +1717,8 @@ ngx_dyups_mark_upstream_delete(ngx_http_dyups_srv_conf_t *duscf)
     ngx_log_error(NGX_LOG_INFO, ngx_cycle->log, 0,
                   "[dyups] delete upstream \"%V\"", &duscf->upstream->host);
 
+    ngx_http_upstream_keepalive_clear_cache_connections(uscf);
+
     ngx_dyups_del_upstream_top_filter(umcf, uscf);
 
     us = uscf->servers->elts;
diff --git a/modules/ngx_http_upstream_keepalive_module/ngx_http_upstream_keepalive_module.c b/modules/ngx_http_upstream_keepalive_module/ngx_http_upstream_keepalive_module.c
index bfe4a401ff..06c4fa0c56 100644
--- a/modules/ngx_http_upstream_keepalive_module/ngx_http_upstream_keepalive_module.c
+++ b/modules/ngx_http_upstream_keepalive_module/ngx_http_upstream_keepalive_module.c
@@ -1105,3 +1105,30 @@ ngx_http_upstream_keepalive_timeout(ngx_conf_t *cf, ngx_command_t *cmd,
     return NGX_CONF_OK;
 }
 
+void
+ngx_http_upstream_keepalive_clear_cache_connections(ngx_http_upstream_srv_conf_t *us) {
+    if (us == NULL) {
+        return;
+    }
+    ngx_http_upstream_keepalive_srv_conf_t *kcf;
+    ngx_http_upstream_keepalive_cache_t *item;
+    ngx_queue_t *q, *cache;
+    kcf = ngx_http_conf_upstream_srv_conf(us, ngx_http_upstream_keepalive_module);
+    if (kcf == NULL || kcf->max_cached == 0) {
+        return;
+    }
+    cache = &kcf->cache;
+    if (cache == NULL || cache->prev == NULL || cache->next == NULL) {
+        return;
+    }
+    kcf->timeout = 0;
+    for (q = ngx_queue_head(cache); q != ngx_queue_sentinel(cache); q = ngx_queue_next(q)) {
+        item = ngx_queue_data(q, ngx_http_upstream_keepalive_cache_t, queue);
+        if (item->connection && item->connection->read && item->connection->read->timer_set) {
+            ngx_del_timer(item->connection->read);
+            ngx_add_timer(item->connection->read, kcf->timeout);
+        }
+    }
+}
+
+
diff --git a/tests/nginx-tests/tengine-tests/dyups.t b/tests/nginx-tests/tengine-tests/dyups.t
index c044425ac6..0b435df6c6 100644
--- a/tests/nginx-tests/tengine-tests/dyups.t
+++ b/tests/nginx-tests/tengine-tests/dyups.t
@@ -569,6 +569,71 @@ unlike(mhttp_get('/', 'dyhost', 8080), qr/8088/m, '5/ 5 11:04:42 2014');
 $t->stop();
 unlink("/tmp/dyupssocket");
 
+##############################################################################
+
+$t->write_file_expand('nginx.conf', <<'EOF');
+
+%%TEST_GLOBALS%%
+
+daemon off;
+
+worker_processes 1;
+
+events {
+    accept_mutex off;
+}
+
+http {
+    %%TEST_GLOBALS_HTTP%%
+
+    resolver_timeout 500ms;
+
+    server {
+        listen   8080;
+
+        location / {
+            proxy_http_version 1.1;
+            proxy_set_header Connection "";
+            proxy_pass http://$host;
+        }
+    }
+
+    server {
+        listen 8088;
+        location / {
+            return 200 "8088";
+        }
+    }
+
+    server {
+        listen 8089;
+        location / {
+            return 200 "8089";
+        }
+    }
+
+    server {
+        listen 8081;
+        location / {
+            dyups_interface;
+        }
+    }
+}
+EOF
+
+mrun($t);
+
+like(mhttp_post('/upstream/dyhost', 'keepalive 32; keepalive_timeout 50s; server 127.0.0.1:8088; server 127.0.0.1:8089;', 8081), qr/success/m, '2024-08-28 14:37:20');
+like(mhttp_get('/', 'dyhost', 8080), qr/8088|8089/m, '2024-08-28 14:37:23');
+like(mhttp_get('/', 'dyhost', 8080), qr/8088|8089/m, '2024-08-28 14:37:26');
+like(mhttp_get('/', 'dyhost', 8080), qr/8088|8089/m, '2024-08-28 14:37:29');
+like(mhttp_post('/upstream/dyhost', 'keepalive 32; keepalive_timeout 60s; server 127.0.0.1:8088; server 127.0.0.1:8089;', 8081), qr/success/m, '2024-08-28 14:37:32');
+like(mhttp_get('/', 'dyhost', 8080), qr/8088|8089/m, '2024-08-28 14:37:35');
+like(mhttp_get('/', 'dyhost', 8080), qr/8088|8089/m, '2024-08-28 14:37:38');
+like(mhttp_get('/', 'dyhost', 8080), qr/8088|8089/m, '2024-08-28 14:37:41');
+
+$t->stop();
+
 ###############################################################################
 # test ssl session reuse