diff --git a/Jenkinsfile b/Jenkinsfile
index 5567036..dcde711 100644
--- a/Jenkinsfile
+++ b/Jenkinsfile
@@ -18,7 +18,9 @@ pipeline {
         WEB_NODE_IMAGE    = 'docker.m.daocloud.io/library/node:22-alpine'
         WEB_NGINX_IMAGE   = 'docker.m.daocloud.io/library/nginx:1.27-alpine'
         HTTP_PROXY_URL    = 'http://192.168.5.200:7890'
-        NO_PROXY_HOSTS    = '127.0.0.1,localhost,reg.nxsir.cn,gitea.nxsir.cn'
+        // Tsinghua/daocloud/mcr hosts are reachable directly from the builder — routing them
+        // through the 7890 proxy caused intermittent '502 Bad Gateway' during apt-get install.
+        NO_PROXY_HOSTS    = '127.0.0.1,localhost,reg.nxsir.cn,gitea.nxsir.cn,mirrors.tuna.tsinghua.edu.cn,.tsinghua.edu.cn,mcr.microsoft.com,docker.m.daocloud.io'
 
         GIT_REPO_URL = 'https://gitea.nxsir.cn/nanxun/live_recorder.git'
         GIT_BRANCH   = 'main'