diff --git a/server/prometheus-service.js b/server/prometheus-service.js
index 0f3dd07..5f6c3e7 100644
--- a/server/prometheus-service.js
+++ b/server/prometheus-service.js
@@ -1,18 +1,35 @@
 const axios = require('axios');
+const http = require('http');
+const https = require('https');
 
 const QUERY_TIMEOUT = 10000;
 
+// Reusable agents to handle potential redirect issues and protocol mismatches
+const httpAgent = new http.Agent({ keepAlive: true });
+const httpsAgent = new https.Agent({ keepAlive: true, rejectUnauthorized: false });
+
+/**
+ * Normalize URL and ensure protocol
+ */
+function normalizeUrl(baseUrl) {
+  let url = baseUrl.trim().replace(/\/+$/, '');
+  if (!/^https?:\/\//i.test(url)) {
+    url = 'http://' + url;
+  }
+  return url;
+}
+
 /**
  * Create an axios instance for a given Prometheus URL
  */
 function createClient(baseUrl) {
-  let url = baseUrl.replace(/\/+$/, '');
-  if (!/^https?:\/\//i.test(url)) {
-    url = 'http://' + url;
-  }
+  const url = normalizeUrl(baseUrl);
   return axios.create({
     baseURL: url,
-    timeout: QUERY_TIMEOUT
+    timeout: QUERY_TIMEOUT,
+    httpAgent,
+    httpsAgent,
+    maxRedirects: 5
   });
 }
 
@@ -20,9 +37,18 @@ function createClient(baseUrl) {
  * Test Prometheus connection
  */
 async function testConnection(url) {
-  const client = createClient(url);
-  const res = await client.get('/api/v1/status/buildinfo');
-  return res.data?.data?.version || 'unknown';
+  const normalized = normalizeUrl(url);
+  try {
+    const res = await axios.get(`${normalized}/api/v1/status/buildinfo`, {
+      timeout: QUERY_TIMEOUT,
+      httpAgent,
+      httpsAgent
+    });
+    return res.data?.data?.version || 'unknown';
+  } catch (err) {
+    console.error(`[Prometheus] Connection test failed for ${normalized}:`, err.message);
+    throw err;
+  }
 }
 
 /**
@@ -51,6 +77,7 @@ async function queryRange(url, expr, start, end, step) {
   return res.data.data.result;
 }
 
+
 /**
  * Get overview metrics from a single Prometheus source
  */