diff --git a/src/main/java/net/lamgc/oracle/sentry/Constants.java b/src/main/java/net/lamgc/oracle/sentry/Constants.java
new file mode 100644
index 0000000..3e89963
--- /dev/null
+++ b/src/main/java/net/lamgc/oracle/sentry/Constants.java
@@ -0,0 +1,28 @@
+package net.lamgc.oracle.sentry;
+
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.lang.NonNull;
+import org.springframework.stereotype.Component;
+
+/**
+ * @author LamGC
+ */
+@Component("sentry.constants")
+public final class Constants {
+
+    public static Constants instance;
+
+    private Constants() {
+        instance = this;
+    }
+
+    @Value("${oracle.ssh.firstConnection.authenticationPolicy}")
+    @NonNull
+    private String firstConnectionPolicy;
+
+
+    @NonNull
+    public String getFirstConnectionPolicy() {
+        return firstConnectionPolicy;
+    }
+}
diff --git a/src/main/java/net/lamgc/oracle/sentry/oci/compute/ssh/OracleInstanceServerKeyVerifier.java b/src/main/java/net/lamgc/oracle/sentry/oci/compute/ssh/OracleInstanceServerKeyVerifier.java
index 99e7bf9..45373ea 100644
--- a/src/main/java/net/lamgc/oracle/sentry/oci/compute/ssh/OracleInstanceServerKeyVerifier.java
+++ b/src/main/java/net/lamgc/oracle/sentry/oci/compute/ssh/OracleInstanceServerKeyVerifier.java
@@ -1,5 +1,6 @@
 package net.lamgc.oracle.sentry.oci.compute.ssh;
 
+import net.lamgc.oracle.sentry.Constants;
 import net.lamgc.oracle.sentry.oci.compute.ComputeInstance;
 import org.apache.sshd.client.keyverifier.RequiredServerKeyVerifier;
 import org.apache.sshd.client.keyverifier.ServerKeyVerifier;
@@ -7,8 +8,6 @@ import org.apache.sshd.client.session.ClientSession;
 import org.apache.sshd.common.config.keys.KeyUtils;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
-import org.springframework.beans.factory.annotation.Value;
-import org.springframework.lang.NonNull;
 
 import java.net.SocketAddress;
 import java.security.PublicKey;
@@ -21,10 +20,6 @@ public class OracleInstanceServerKeyVerifier implements ServerKeyVerifier {
 
     private final static Logger log = LoggerFactory.getLogger(OracleInstanceServerKeyVerifier.class);
 
-    @Value("${oracle.ssh.firstConnection.authenticationPolicy}")
-    @NonNull
-    private static String firstConnectionPolicy;
-
     private final ComputeInstance instance;
     private final SshAuthInfo info;
 
@@ -53,11 +48,12 @@ public class OracleInstanceServerKeyVerifier implements ServerKeyVerifier {
     }
 
     private boolean usePolicyConfirm(SocketAddress address, PublicKey serverKey) {
+        String policyName = Constants.instance.getFirstConnectionPolicy().toUpperCase();
         FirstConnectionPolicy policy;
         try {
-            policy = FirstConnectionPolicy.valueOf(firstConnectionPolicy.toUpperCase());
+            policy = FirstConnectionPolicy.valueOf(policyName);
         } catch (IllegalArgumentException e) {
-            throw new IllegalArgumentException("Unsupported policy: " + firstConnectionPolicy);
+            throw new IllegalArgumentException("Unsupported policy: " + policyName);
         }
         return policy.confirmFunction.confirm(this.instance, address, serverKey);
     }